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I think revetec engine is crap. sorry.
I am brave enough to say that in 5 to 10 years time the company will be bankrupt.
I can explain what is wrong with the design but it would take forever because people will keep arging esp Mr revetec (of course) even if they do not know.
There are hundreds if not thousands of new engine designs and patents trying to replace the most feasible crankshaft piston engine but none will replace it. A few alternative engines such as wankel (maybe quasiturbine) might be the powerplant in less than 0.5 % of future vehicles. The future would be hybrid and pure electric (fuel cells, battery).
For those who does not know engineering......
Believe me time will tell. Even now you can see that there is no interest from major manufacturers. Why wouldn't they just take or license the patent if it is so good, install in their cars and providing customers better products for the sake of their own company. They sooner they can make agreement with revetec the better. BUT revetec has been around for more than 10 years and they are not interested. If Mr Revetec went to mazda to explain his invention and the head of R&D agree with him, why didn't the head of R&D just license the patent. Or borrow a few units for testing. But of course they would not tell if there is any flaw in the design a few days after the discussion because that would hurt Mr. revetec's feeling and Australians might boycott mazda cars. They would not do anything that might affect the image of mazda. They just say NOT NOW.
Do not just say I am talking rubbish. I even read an article about Revetec in either SAE magazine or Engine Technology International and I think it was in 2004 or maybe 2003. Even the author had a bad feeling about the engine.
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[quote=hightower99]Too bad you can't smell CO2... ;)[/quote]
oh dear :(
Carbon Monoxide ( CO ) is odourless.
Carbon Dioxide ( CO2 ) has a faint, sharp odour and a slightly sour taste.
Hopefully the above was a typo and not another misconception :(
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[quote=taik]For those who does not know engineering......
Believe me time will tell. Even now you can see that there is no interest from major manufacturers. Why wouldn't they just take or license the patent if it is so good, install in their cars and providing customers better products for the sake of their own company. They sooner they can make agreement with revetec the better. BUT revetec has been around for more than 10 years and they are not interested. If Mr Revetec went to mazda to explain his invention and the head of R&D agree with him, why didn't the head of R&D just license the patent[/quote]
Because major companies cannot allow early patent holders to describe their inventions as it can significantly weaken patent protection in the future. So if say Mazda looked closely at the Revetec engine 10 years ago and said no and then later on an engine patent turned up with even only 1% of the features or techniques then their patent coudl be void. Revetec would then have "Leveraged" a patent value far in excess of it's relvance at the time.
So that's why majro design and manufacturing groups wait till near 100% proven before going in to technical details -- or they sometimes employ external companies to review and provide reports, but these also have dangers for both parties.
[quote]They just say NOT NOW.[/quote]
At least now you know the real reason why "not now" :D
[quote]Do not just say I am talking rubbish.[/quote]
Well saldy, you are on the way businesses today approach novel inventions.
[quote]Even the author had a bad feeling about the engine.[/quote]
True and entitled to them and as you already said, thousands of new ideas for engine improvement surface every year. So early on it is hedging the bet to be sceptical !!
There ARE obvious benefits, but whether they deliver those before material technologies enable the standard layout to match is still a question that Revetec shareholders are betting on.
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[QUOTE=taik]
I am brave enough to say that in 5 to 10 years time the company will be bankrupt.[/QUOTE]
It takes a brave man.
[QUOTE=taik]
I can explain what is wrong with the design but it would take forever because people will keep arging esp Mr revetec (of course) even if they do not know.[/QUOTE]
I'll just take your word for it.
Interesting it is your first post. You wouldn't be from Greece by any chance? Maybe related ;)
[QUOTE=taik]The future would be hybrid and pure electric (fuel cells, battery).[/QUOTE]
Have you read any of this thread? I'm sure Brad covers something about hybrid cars and REVETEC.
[QUOTE=taik]Even now you can see that there is no interest from major manufacturers. Why wouldn't they just take or license the patent if it is so good, install in their cars and providing customers better products for the sake of their own company.[/QUOTE]
Once again, have you read any of this thread?
[QUOTE=taik]I even read an article about Revetec in either SAE magazine or Engine Technology International and I think it was in 2004 or maybe 2003. Even the author had a bad feeling about the engine.[/QUOTE]
Please direct us to this article so we can read the author's comments. Every article I have read about REVETEC in a magazine has not mentioned any bad remarks from the author and trust me, I have read probably every one in the last ten years.
BTW the engine of today is much improved on the 2003 design.
[QUOTE=taik]Do not just say I am talking rubbish.[/QUOTE]
No need to say it. You are doing a good job with your keyboard.
You [B]must[/B] be related.
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Actually I still have the magazine at home. It was from Engine Technology International June 2005. There were many question marks that the author raised about the the unproven claims. And for conclusion even if they can prove their claims there will still be issue about heat rejection. Of course engineers should know that there must be heat rejected form a heat engine. That is the law of thermodynamics. So there will be issue about cooling, AND also cost in general. But even now to me they still cannot prove it. Proving it would not break your company rules, in fact it is good so that others know.
I know a lot about cars, I am an engineer but not from Australian (not the reason why I have said all this) and I graduated from one of the best universities in the world in Mechanical Engineering. Yes I cannot prove and would not prove who I am. If you do not believe me it is OK. I beleive in my engineering skills and knowledge and I can see that it will not be there.
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[QUOTE=CHOOK]Brad, I read this article on ninemsn tonight.
Have you got any figures on the emissions of the current design? I remember at a REVETEC open day a few years ago where you had a previous engine running that you could put your nose right next to the exhaust and could hardly smell any exhaust.
Thanks[/QUOTE]
We will sort out the emissions when we inject the engine. The Aircraft version is running carburettors (For safety/battery power loss) so the emissions on the aircraft version will be a little higher than they will finally be. Our other injected engines have been very low in emissions, so no prob.
I can remember the 2000 model. When I displayed the engine at an open day, I brought the revs up to 2,000 RPM inside the closed factory. Everyone was standing in front of the engine. After a few minutes someone said where is the exhaust going? It was pointing straight at everyone behind a mesh grill so everyone could not see it. I removed the mesh and everyone was amazed at the very low exhaust gas flow and everyone had a go at feeling it. One guy put his nose to it and said that he couldn't smell anything. It was quite funny to see everyone's reaction that day. Thanks for reminding me of a memorable moment.
I can remember the bet about running across the Harbour bridge naked too. Hahahah!
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[QUOTE=taik]There are hundreds if not thousands of new engine designs and patents trying to replace the most feasible crankshaft piston engine but none will replace it.
The future would be hybrid and pure electric (fuel cells, battery).
For those who does not know engineering......
Believe me time will tell. Even now you can see that there is no interest from major manufacturers.
If Mr Revetec went to mazda to explain his invention and the head of R&D agree with him, why didn't the head of R&D just license the patent. [/QUOTE]
Your first statement is a bold one. There are many engines in development but they are either complex and costly, or the benifits are small which doesn't make it viable when retooling costs are brought into play.
The far distant future is hybrid. They still require a power plant to drive a reasonable distance. Battery technology is not cost effective enough currently. The fuel savings of a Hybrid are currently offset with the replacement costs of the battery replacement (normal life) which overall doesn't provide any really cost savings in running costs. The purchase price is higher at the moment too.
We have signed one contract to supply engines. We are currently going through the testing stage with two major manufacturers, so your comments are incorrect. One has been announced on our website.
Mazda were interested and a discussion was made about the relationship and licensing. They required exclusivity which we are not going to do. I told them we were planning to manufacture in India and that in a couple of years they could purchase engines of us.
One question? Are you a mate of manolis? :rolleyes:
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[QUOTE=Matra et Alpine]oh dear :(
Carbon Monoxide ( CO ) is odourless.
Carbon Dioxide ( CO2 ) has a faint, sharp odour and a slightly sour taste.
Hopefully the above was a typo and not another misconception :([/QUOTE]
What was experienced was a free revving engine at 2,000rpm and the energy required to do this on our engine is very small, so the exhaust gas flow was very small. It was done in an unvented room for a few minutes and no one could smell any fumes. If you are to do this will a conventional engine you would smell the exhaust fumes. I think this was his thoughts.
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After presenting to car companies, universities and all the media coverage(There has been a lot of it over the years) No one has been able to find any fault that I haven't already solved. No one in the automotive industry has been able to find a fault in any theory or designs I have presented.
That is why companies like Elf, SKF, Recoil Electrosil and Haltech are strategic development partners. I met with Castrol/BP in the UK at their R&D head office a few months ago to present a total overview of or engine. I presented to 6 top engineering professors in all aspects of engines including thermal, mechanical and lube.They stated it was a step up technology and that they were interested in getting involved in our project.
[B]As for taik[/B] a university graduate, So you have read textbooks.
What is your experience in engines and the automotive industry?
Who do you work for? Because if you don't work for a major automotive manufacturer, then your just blowing your horn.
I know a university graduate in mechanical engineering who designs toothpick making machines, and know little about engines as an example that just because you have a bit of paper, it doesn't make you an expert in everything.
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Dear Taik: Here is their article on alternative engines.
[SIZE="4"][B]Updated article from Engine Technology International 2006[/B][/SIZE]
[IMG]http://i84.photobucket.com/albums/k6/revetec/automan2006.jpg[/IMG]
The previous article in 2005 was before testing, so i suppose they said they didn't know how that engine would perform at the time.
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[QUOTE=RVC Shareholder]I too am a shareholder. One of the early ones (I think) when the engine was just a humble garage built prototype.
I have that much faith I have already picked out my new red Ferrari (well almost)
Hi Brad, do you know who this is? clue....Are you still going to hold me to running naked across the harbour Bridge when I make my first Million?
I'm almost there now so this will be icing on the cake and a potential early retirement fund.
Stop reading this post and get back to work and make me money on my investment![/QUOTE]
Ha ha! Only posting here when I have a spare moment. I do work 12-16 hours a day with 5 hours sleep. I think I'm allowed 1/2 an hour on here every few days. :)
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[QUOTE=taik]I think revetec engine is crap. sorry.
[QUOTE]I am brave enough to say that in 5 to 10 years time the company will be bankrupt.[/QUOTE]
[COLOR="Red"]If you are that brave then dont use an alias. How about you state your professional name on this quote of yours. [/COLOR]
[QUOTE]I can explain what is wrong with the design but it would take forever because people will keep arging esp Mr revetec (of course) even if they do not know.[/QUOTE]
[COLOR="red"]That is so big of you. Like I have said before, it is insignificant people like you that will make the Revetec engine a success because it is people like you who have no real say on anything of any significance. Consider the question... what if... consider what if Brad has access to data that you dont have access to about his engine. Then maybe he can make claims about his engine that he can back-up when the TIME IS RIGHT. [/COLOR]
[QUOTE]There are hundreds if not thousands of new engine designs and patents trying to replace the most feasible crankshaft piston engine but none will replace it. A few alternative engines such as wankel (maybe quasiturbine) might be the powerplant in less than 0.5 % of future vehicles. The future would be hybrid and pure electric (fuel cells, battery).[/QUOTE]
[COLOR="red"]You are a nob, have you ever thought that this engine can be integrated within a hybrid powertrain? The most ineffecient aspect of the Toyota synergy drive system is its 1.5 litre petrol engine that weights a tonne. If you integrated Brad's engine within a hybrid powertrain it would weigh less, offer better power and torque and better fuel economy and fuel emissions.
As Brad has stated he has this technology in the pipeline.
God blessed you with a brain, try using it.
[/COLOR]
[QUOTE]For those who does not know engineering......
Believe me time will tell. Even now you can see that there is no interest from major manufacturers. Why wouldn't they just take or license the patent if it is so good, install in their cars and providing customers better products for the sake of their own company.[/QUOTE]
[QUOTE]They sooner they can make agreement with revetec the better. BUT revetec has been around for more than 10 years and they are not interested. [/QUOTE]
[COLOR="red"]You are a novice and a fool, stick to the how to bake a cake forums. [/COLOR]
[QUOTE]If Mr Revetec went to mazda to explain his invention and the head of R&D agree with him, why didn't the head of R&D just license the patent. Or borrow a few units for testing. But of course they would not tell if there is any flaw in the design a few days after the discussion because that would hurt Mr. revetec's feeling and Australians might boycott mazda cars. They would not do anything that might affect the image of mazda. They just say NOT NOW.[/QUOTE]
[COLOR="red"]What nonsense is that, it doesnt work that way you fool. It has taken Brad 10 years to develop this engine based on a limited budget and resources. It took Toyota $1 billion dollars and 10 years plus over 800 engineers to develop their hybrid engine. How can you sit there and make such comments. [/COLOR]
[QUOTE]Do not just say I am talking rubbish. I even read an article about Revetec in either SAE magazine or Engine Technology International and I think it was in 2004 or maybe 2003. Even the author had a bad feeling about the engine.[/QUOTE][/QUOTE]
[COLOR="red"]It is too early to cast dispersions about this technology. Dont go making comments or criticisms without having the facts. You are a goose, you are a nob and give yourself a triple by-pass uppercut for your stupidity. [/COLOR]
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[QUOTE]I know a lot about cars, I am an engineer but not from Australian (not the reason why I have said all this) and I graduated from one of the best universities in the world in Mechanical Engineering. Yes I cannot prove and would not prove who I am. If you do not believe me it is OK. I beleive in my engineering skills and knowledge and I can see that it will not be there.[/QUOTE][/QUOTE]
[COLOR="Red"]I didn't realise they handed out engineering degrees at your local McDonalds. Dont be too concerned, if you ever run out of toilet paper you can always use your degree to wipe your a&se. The key concern for you is knowing which orifice to wipe, your mouth or the other hole. [/COLOR]:)
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[URL="http://minister.industry.gov.au/index.cfm?event=object.showContent&objectID=F0B38D07-F310-295E-851AE25C229826AD"]Media release
Federal Government Grants
The Hon Ian Macfarlane, MP
Australian Industry Minister[/URL]
Media Release
The Hon Ian Macfarlane, MP
8 January 2007
QLD AIRCRAFT TAKES OFF WITH LESS FUEL AND FEWER EMISSIONS
Australian Industry Minister Ian Macfarlane today announced Australian Government innovation funding for a Surfers Paradise company to develop a more fuel efficient and environmentally friendly engine for sport and recreational aircraft.
Mr Macfarlane said Revetec would receive more than $1 million through the Commercial Ready programme to help bring the product to market.
"This is a fantastic development and exactly the type of innovation this program is designed to support," Mr Macfarlane said.
"On top of this, it's great to see that even in the sport and recreation area, Australia’s innovators are looking at ways to reduce emissions."
Mr Macfarlane said the proposed 2.4 litre combustion engine will use unleaded and JP8 fuel with an output in excess of 82 kw and 262 Newton metres (Nm) while being 25 per cent more efficient.
Its main competitor is a 2.2 litre engine with less power output. [Contact: Revetec Holdings Ltd, Mr C Chan 07 5531 6059]
Revetec is one of eight Queensland companies sharing in $1.8 million through the latest round of Commercial Ready and Commercialising Emerging Technologies (COMET) funding
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Note: Only AUD$1.8 million was given out in Qld and Revetec recieved over AUD$1 million.
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I spent a few hours thinking on how to “prove” I am not an elephant. I cannot.
I was surprised by the “level” of taik’s arguments.
If taik is not a real person, then he is invented by a sick/disordered mind.
Follow the best advice Andy Grove of Intel ever took:
“Base knowledge on facts and analysis rather than on what everybody knows. When everybody knows that something is so, nobody knows nothing.”
Felix Wankel was nothing but a “high school boy”, an insignificant and poor “self educated machinist”.
He followed his dream and offered to the world more than many thousands of university professors and overqualified engineers.
Thank you
Manolis Pattakos
PS1
Revetec, without having finished even the parts of their first X4 prototype (Jan 8, 2007), will take more than one million dollars because their engine “will be” so good. This is what I call success. Congratulations to Revetec.
Pattakon’s GRECO i3 [url]www.pattakon.com/greco/Grecoi3.exe[/url] impatiently waits for the real success of Revetec X4.
PS3
Australia is a great county, deeply concerned about global warming.
Australia has an Embassy and an Ambassador in Athens, and probably technical staff.
If the Minister of Industry of Australia is an environmentalist like Al Gore (USA ex-vice), he can whisper to his Ambassador to call me to bring, at the gate/port of the embassy, the prototype cars of Pattakon.
We can run the prototype cars on pure ethanol, if he likes so.
Have anybody smelled the exhaust pipe of a car burning pure ethanol?
It smells like a distillery/pub
[url]www.pattakon.com/vva/VVA_Idle/VVA_Idle.htm[/url]
PS4
Once again, many Thanks to the Revetec Team for finding the worst flaws and blunders of Pattakon’s PRE and GRECO engines.
Please keep on with the rest of Pattakon engines in [url]www.pattakon.com[/url]
And according the decision of the Australian Minister of Industry, Revetec is now the State-of-the-Art in Australia.
From now on, the disapproval of an engine by Revetec has another weight.
Thanks
Manolis Pattakos
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[QUOTE=manolis]
PS1
Revetec, without having finished even the parts of their first X4 prototype (Jan 8, 2007), will take more than one million dollars because their engine “will be” so good. This is what I call success. Congratulations to Revetec.
Pattakon’s GRECO i3 [url]www.pattakon.com/greco/Grecoi3.exe[/url] impatiently waits for the real success of Revetec X4.
Thanks
Manolis Pattakos[/QUOTE]
The X4 parts are finished....We are just finalising parts like thermostat housing and dipstick etc... The first evaluation engine has only taken AUD$500k from start to finish. Further funds will be spent on production designing and fine tuning. So stop making uninformed silly comments!
[IMG]http://i84.photobucket.com/albums/k6/revetec/X4manifolds2.jpg[/IMG] [IMG]http://i84.photobucket.com/albums/k6/revetec/X4manifold1.jpg[/IMG]
The above picture was taken a month ago before internals were fitted. [B]Currently the internals are all fitted.[/B]
CD carburettors and dual Magnetos/plugs are fitted for aircraft safety from power failure. 95% has been built inhouse.
[B]X4 aircraft engine setup mounted to the aircraft airframe, which has been mounted on our dynamomenter.[/B]
Note: Intakes are calculated length to provide RAM induction at the desired operational speed.
After initial testing, fuel injection will be added for other markets including GTM trikes.
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[quote=manolis]Felix Wankel was nothing but a “high school boy”, an insignificant and poor “self educated machinist”.
He followed his dream and offered to the world more than many thousands of university professors and overqualified engineers. [/quote]
A beleif in that probably explains why you think you're approach might succeed.
However, those aren't the facts.
Yes he was in the main self-educated ... but by reading the works of many researchers in the university he worked.
Yes he came from a poorer family - but so did most who lived in that time in Germany. 1000% inflation can do that to you :D
The working DKM engine was a collaboration, directed by Wankel's efforts but not solely.
Hoep you didnt' rely on WIKI for your background on Wankel !"!!!!!
Jeez, Brad, that is looking sweet in the plane support frame. VERY short. How long do you think it will realistically take to get aviation certificatino for it ?
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We are going into uncertified sport/recreational and military uses first. You need to fly 200 hours and inspect to give service schedules and life to overhaul.
We will certify later as this is costly and time consuming. Uncertified aircraft is around a US$6 billion a year market.
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Revetec: “So how much more power?
It is now 5 years since the Patent was lodged on a camshaft design. The engine tacho shows it goes to 9,000rpm, so the engine is running. How about posting a dyno graph which is third party certified to show us the improvements over the standard engine. If it is better I'm even interested.”
I am interesting too, in a few details of Revetec’s design, for the sake of Pattakon GRECO I3 at [url]www.pattakon.com/greco/Grecoi3.exe[/url] (a true “thrust free” engine), but Revetec persistently keeps the precious secrets. Even the Bore and the Stroke.
Checking US-PTO for Revetec’s patents, what I see is that the first basic design of their engine was longed on July 1995.
If, after 11.5 years (i.e. 5.5 years before patent expiration) and millions of dollars from their share holders, Revetec’s best dyno graph is the one for RHL4 1400cc finishing at 4600 rpm (which actually is not good news for Pattakon’s GRECO engines future), Revetec should be more patient and less arrogant with Pattakon’s “delay”.
As regards the power, I admit that Revetec’s RHL4 (1400cc) makes more power than the one cylinder of Pattakon’s prototypes, either with the light version Honda B16A (1600cc) at [url]www.pattakon.com/vvar/VVAL.htm[/url] or with the full version Honda B16A [url]www.pattakon.com/vvar/OnBoard/[/url] . And I estimate that neither VTS [url]www.pattakon.com/vts/[/url] (1600 cc Citroen) with only one working cylinder (i.e. with the other three cylinders deactivated) and without supercharging would be able to win the RHL4. But with two cylinders deactivated and two working (of anyone of the above Pattakon prototype engines), the Revetec RHL4 has no chance at all.
When the new 2400cc Revetec engine is ready, we’ll see how many cylinders to deactivate. Two or one?
As for the Pattakon PRE single cylinder, 515cc, naturally aspirated, direct injection opposed piston Diesel engine ( [url]www.pattakon.com/pre/PE14.exe[/url] and [url]www.pattakon.com/pre/droplet.exe[/url] ) I dare say it will provide similar power to the Revetec RHL4.
Thanks
Manolis Pattakos
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[QUOTE=manolis]Revetec : “Or do they hope to overcome problems at a later date?”
Revetec knows better than anyone else.
Unless Revetec applied for a patent with all problems solved.[/QUOTE]
For a start, we are an honest company and we have not and never get into the practice of modifying and taking out new patents of other peoples technology.
[QUOTE=manolis]Revetec: “So how much more power?
It is now 5 years since the Patent was lodged on a camshaft design. The engine tacho shows it goes to 9,000rpm, so the engine is running. How about posting a dyno graph which is third party certified to show us the improvements over the standard engine. If it is better I'm even interested.”
I am interesting too, in a few details of Revetec’s design, for the sake of Pattakon GRECO I3 at [url]www.pattakon.com/greco/Grecoi3.exe[/url] (a true “thrust free” engine), but Revetec persistently keeps the precious secrets. Even the Bore and the Stroke.[/QUOTE]
After a huge amount of time performing analysis, as if I'm going to tell you details like that? Come on....be sensible...would you release that info to me if the situation was reversed? I bet not.
[QUOTE=manolis]Checking US-PTO for Revetec’s patents, what I see is that the first basic design of their engine was longed on July 1995.
If, after 11.5 years (i.e. 5.5 years before patent expiration) and millions of dollars from their share holders, Revetec’s best dyno graph is the one for RHL4 1400cc finishing at 4600 rpm (which actually is not good news for Pattakon’s GRECO engines future), Revetec should be more patient and less arrogant with Pattakon’s “delay”.[/QUOTE]
Early history of our company was that we were under funded for the first 6 years.
Let's look at Revetec Today. The X4 concept was designed on 10 July 2006. Patents were lodged in August 2006. X4 first evaluation/build design was completed November 2006. Engine completed in two weeks (fully dressed and running February 2006. We now have a fresh patent 20 years (not the 17 you stated because you probably don't know about the 36 month extension you can make for the PCT.
[QUOTE=manolis]As regards the power, I admit that Revetec’s RHL4 (1400cc) makes more power than the one cylinder of Pattakon’s prototypes, either with the light version Honda B16A (1600cc) at [url]www.pattakon.com/vvar/VVAL.htm[/url] or with the full version Honda B16A [url]www.pattakon.com/vvar/OnBoard/[/url] . And I estimate that neither VTS [url]www.pattakon.com/vts/[/url] (1600 cc Citroen) with only one working cylinder (i.e. with the other three cylinders deactivated) and without supercharging would be able to win the RHL4.[/QUOTE]
Well to this date, everyone has been asking for figures from you and nothing has been posted.
Let's look at your statement because we are going to be talking about power per litre at a certain RPM range. Higher the Revs the more power it is possible to produce. We are loking at efficiency not outright performance.
[B]If what you say is correct, then one cylinder of your 1600cc 4 cylinder engine is 400cc. This 400cc your quoting will have to make about 58kW at 4,200rpm normally aspirated to be equal to our old engine.
By your statement are you saying that you can produce 145kw or about 200hp per litre at 4,200rpm?
OK...BMW M6 produces 100hp per litre at 7,750rpm. If you look at the dyno graph of the M6, at 4,200rpm it is producing about 50Hp per litre.
So your saying that you can produce 4 times the power per litre at the same speed as our tested engine and than the BMW M6 at the same RPM?[/B]
You are the funniest person I have ever had contact with. At our tested peak power point of our old 1350cc engine we are producing about the same power per litre as the M6 at 4,200rpm but our fuel consumption is less.
Just by having variable valve timing, you are not going to produce 4 times the power per litre.
If the point you were making about your engine is able to rev to 9,000rpm then your fuel will at least double to do so. Anyways this still means you are saying that you can make twice the power (apples for apples) per litre than the BMW M6 with modifying a Citroen 1600cc with your VVT?
Impossible and a stupid statement.
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MISTAKE
First I have to correct a mistake I made.
I wrote that Revetec’s patent has 5.5 years before expiration (this was the law a couple of years before).
The correct is that Revetec’s patent has 8.5 years before expiration.
DESMO
The desmo valves is a completely “correct” geometry.
The “eye” like member is always in contact to both lobes: the internal (or conventional) lobe and the external lobe.
The “eye” like member is actually the section of two cylinders.
A simple way to made the Pattakon desmo camshaft ( [url]www.pattakon.com/greco/Desmo2D.exe[/url] and [url]www.pattakon.com/greco/Desmo3D.exe[/url] ) has been already described by another’s post.
After the internal cams are grinded on a shaft (just like in normal camshafts) the external cams are secured properly to the basic camshaft.
The assembly of the rest parts is much more easy than initially seems: through a side hole in the “external” cam, the “eye” like member is inserted in its working place.
The valve stem passes through a hole on the “eye” like member (or cam follower if you prefer) and is secured and aligned by a pair of nuts.
An elastic washer (i.e. a strong spring of very short stroke) inserted between the “eye” like member and the valve stem is used to take the lash and the thermal expansion.
The system is much more light, compact and robust than the known desmo systems.
If it fails to work in practice, nobody is going to get hurt.
But think, if it works, why F1 engines need pneumatic valves any longer.
PORTABLE FLYER
There is a great difference between the synchropter shown in the picture and the Portable Flying Machine ( [url]www.pattakon.com/fly/Flyer4.exe[/url] ). In a helicopter you cannot change the position of the center of gravity compared to the rotors.
In the portable flyer, the pilot/rider can displace his body compared to the engine/rotors.
This is enough to give absolute control of the flight.
Just think that the pilot can slightly change the revs of the engine to keep the Flyer hovering. A little more throttle and the Flyer moves slowly upwards, a little less throttle and the Flyer moves slowly downwards ( [url]www.pattakon.com/fly/Flyer5.exe[/url] ) .
As the pilot/rider pulls or pushes the “grips” (or handlebars), what he is actually doing is that he displaces his center of gravity relevant to the rotors. This is more than enough. No need for pitch control, no need for electronic sensors and servo mechanisms (the body is the best sensor ever).
GRECO i3
The Greco i3 ( [url]www.pattakon.com/greco/Grecoi3.exe[/url]) has absolutely zero inertia forces, inertia moments and inertia torques (case of sinusoidal piston motion). There is no conventional engine better balanced than this 3 cylinder. Only the rotary Wankel has similar balance quality.
To get the importance of the zero inertia torque of the Greco i3, compare it to an even firing four stroke, four cylinder engine like the X4.
The X4 has a significant inertia torque: when the two pistons of X4 are at TDC, the other two are at BDC, which means that all pistons of X4 are immovable simultaneously, i.e. they have zero kinetic energy.
At the middle of the stroke of a piston, all pistons of X4 have near their maximum velocity simultaneously, i.e. they all reach their maximum kinetic energy simultaneously. In other words, the kinetic energy of the four pistons of the X4 changes from zero to a maximum, two times per piston reciprocation. This, in turn, is translated into variable velocity of the output shaft : for instance when the engine operates at 5000 rpm, if you measure the instant angular velocity of the output shaft of the engine it will be lower (let say 4900 rpm) when the pistons pass through the middle of their stroke and higher (let say 5100 rpm) when the pistons are at their TDC and BDC. The less the flywheel moment of inertia, the more the change of the angular velocity during a cycle. Using elastic absorbers between the output shaft and the helix / rotor / load in order to rectify this irregularity, a part of the energy is lost.
Each piston of X4 has two heavy rollers that move together with the piston. So, at TDC there are eight heavy rollers (heavy because they have to be of yoke type) and four pistons and two “plates” interconnecting each pair of pistons (and keeping the “shafts” of the roller), all immovable. “Half of a piston stroke” later, the eight heavy rollers and the four pistons and the two “interconnecting plates” have reach their maximum speed, i.e. their kinetic energy is at maximum. “Half a piston stroke” later, the pistons, rollers and plates are all immovable again. In other words, at high revs there is a tremendous energy oscillation (this is the meaning of the high inertia torque of the even firing four stroke four cylinder engine, as compared to the six in line or V8 etc).
In the case of the Greco i3, the total kinetic energy of the three pistons is always constant. When a piston assembly losses kinetic energy (i.e. losses speed) the other two absorb exactly the same amount of energy. This means that when the engine operates at 5000 rpm without load, no matter at what specific angle of the main shaft the revs were instantly measured, they are always 5000 rpm. The helix / rotor take only combustion torque from the main shaft.
The rollers of the Greco i3 can be similar to the light needle roller bearings shown at [url]www.pattakon.com/greco/GrecoSingleCylinderWallDisassembly.exe[/url] and [url]www.pattakon.com/greco/GrecoSingleCylinderCylinderWall[/url] . Instead of having the roller bearing rolling on the cam, you can have light “wheels” (like train wheels) rolling on the cams with the needle roller bearing “nested” into the aluminum of the piston.
Having a unique cylinder head of the conventional type (DOHC, 4 valves per cylinder etc) is significant.
The simple synchronizing gearing (including only two spur gears) between the two “shafts” is also significant.
The absolute absence of thrust loads (truly “thrust free” engine) is also important.
If necessary, the Greco i3 can easily change to an even firing six cylinder engine, like the Greco U6 shown at [url]www.pattakon.com/greco/GrecoU6.exe[/url] . This engine has the length of the conventional three in line (and less height) and uses a unique cylinder head (like the VR6 of VW) etc etc.
Both Greco i3 and Greco U6 are true alternatives of conventional, offering many more than just “improved” thermal efficiency.
They can be used not only in airplane applications but in any application the conventional is currently used.
Think the case Revetec adopted the Greco i3 and Greco U6 engines and imagine what arguments they could use to “beat” the conventional engines in every application. Compare the case to the present position of Revetec in engine market.
If the only real problem of the Greco i3 is the difficult finishing of its “cams”, this is nothing.
Revetec knows the reliability of such a design. Pattakon does not, yet.
If there is no such reliability “problem”, the benefits the Greco i3 design brings about are great.
Greco i3 can be a WIN – WIN case (business is business and Australia is Australia). Doesn’t it, Revetec?
Thanks
Manolis Pattakos
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DO NOT POST THE SAME THING IN TWO THREADS.
Just makes the effort look silly
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Yes manolis: Paste your silly replies under your own engine thread only...I responded to you there...if anyone wants to see my response go to the thread on: Pattakon engine.....legitimate alternative or just another fly-by-night.
[B]BTW: You still haven't answered any questions asked on your thread. I think this is because you can't answer them.[/B]
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UGS who make Solid Edge (CAD) and FEMAP Analysis (Nastran FEA, Flow Solver, Thermal Solver) has featured Revetec's X4 on the front of Solid Edge's new Version 20 box. Link: [URL="http://www.velocityseriesinsider.com/articles/feature_image.asp?issue=13"]X4 on Solid Edge Ver.20[/URL]
[IMG]http://i84.photobucket.com/albums/k6/revetec/sev20splashscreen_Final.jpg[/IMG]
I supplied an internal design as well to UGS which I told them to keep confidential. They were amazed at the complexity of the design work versus the 3 and a 1/2 months I took to complete the design and analysis. I didn't expect them to put it on the box, so I'm pretty stoked. We are also the current featured image on their website.
Revetec uses and recommends UGS's Solid Edge and Femap.
We have now fired up our X4 engine (Pictures below: Sitting on our dynamometer). We are currently tuning and "running in" the engine. Performance and fuel usage figures in about 3-4 weeks. The X4 only took 7 months from conception to completion. This involved first concept, conceptual designs, international patent application (PCT), engine specs and research of engine dynamics, main design and stress analysis, machining of parts including block, barrels and liquid cooled cylinder heads (90% in-house), Custom building of parts like manifolds etc, Selection of ancillaries such as water pump and starter motor etc, Mounting on the aircraft frame and dyno, All plumbing, and Design electrical circuits and ignition systems. All in all about 2,500 man hours.
[IMG]http://i84.photobucket.com/albums/k6/revetec/X4logo.jpg[/IMG]
[IMG]http://i84.photobucket.com/albums/k6/revetec/X4dyno3.jpg[/IMG] [IMG]http://i84.photobucket.com/albums/k6/revetec/X4dyno2.jpg[/IMG]
Some of the X4 Engine Features:
2.4 litre 4 cylinder "X" engine;
Avgas fueled Aircraft engine (JP8 fueled version late 2007);
Twin counter-rotating Trilobe drive cams (No Crankshaft);
9:1 compression ratio (1.6mm head gskt) [COLOR="DarkRed"]Current[/COLOR];
9.5:1 compression ratio (1.2mm head gskt);
Liquid cooled billet Barrels and Cylinder heads (Totally CNC Machined);
Total Seal Piston rings (Gapless);
Twin plugs and staggered timing electronic ignition systems (TSEIS);
Extended piston dwell with mid-high RPM lean burn;
Near constant torque lever through 90% of stroke;
Ram induction intake.
Hey Shanetrike....It'll look pretty good in the GTM trikes eh?
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AWESOME RESULT BRAD!!!
Making the Box Cover of SOLID EDGE is simply amazing!
The X4 looks awesome and is an incredible result. I can't wait to get it in the trike.
Brad is taking internal combustion engine theory and design to the next level. Maybe the comment Charles made about you in 2005 was in fact closer to the truth then I thought...
Brad you are a GENIUS.
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At last I found out Revetec’s Bore and Stroke (thanks to the second head gasket).
I copy from Revetec:
“Some of the X4 Engine Features:
2.4 litre 4 cylinder "X" engine;
Avgas fueled Aircraft engine (JP8 fueled version late 2007);
Twin counter-rotating Trilobe drive cams (No Crankshaft);
9:1 compression ratio (1.6mm head gskt) Current;
9.5:1 compression ratio (1.2mm head gskt);
Liquid cooled billet Barrels and Cylinder heads (Totally CNC Machined);
Total Seal Piston rings (Gapless);
Twin plugs and staggered timing electronic ignition systems (TSEIS);
Extended piston dwell with mid-high RPM lean burn;
Near constant torque lever through 90% of stroke;
Ram induction intake.”
Provided the above data of Revetec are correct, with S the stroke of the X4 and D the equivalent height of the dead volume and 9:1 compression ratio, we have:
(S+D)/D=9.0, i.e. S=8.0*D
When the D is decreased for 0.4 mm (1.2 mm head gasket instead of the 1.6 mm head gasket), the compression ratio becomes 9.5 which means that:
(S+D-0.4)/(D-0.4)=9.5 or equivalently (8*D+D-0.4)=9.5*D-9.5*0.4 or equivalently 0.5*D=8.5*0.4 or equivalently D=6.8 mm (and so S=8*6.8mm=54.4mm)
So, the X4 (four cylinder, 2,400 cc) has 54.4mm stroke.
If each cylinder of X4 is 600cc and B is its Bore, we have :
600=pi*S*B*B/4, i.e. B=118.5mm
I.e. Revetec X4 has 118.5 Bore and 54.4 Stroke (both in mm)
This means the Stroke is 46% of the Bore (just about the Stroke to Bore ratio used in Formula 1, GP and in the short stroke GRECO animation at [url]www.pattakon.com/greco/GrecoShortStrokeDis.exe[/url] and [url]www.pattakon.com/greco/GrecoShortStroke[/url] ).
With 50 bar combustion pressure (and piston area=pi*B*B/4, i.e. 110 square centimetres), the force on the two rollers is 5.5 tons. If I knew the offset of the two rollers, I could compute the torsional (twist) thrust loads.
If Revetec gave the correct data, the surface to volume ratio of the combustion chamber compares, if not exceeds, that of Wankel rotary ( like Mazda RX8 ).
Either it is a super-over-square cylinder with 118.5mm Bore for 54.4mm Stroke, or the data given about the gaskets and the compression ratios are wrong.
Mathematics cannot lie.
Thanks
Manolis Pattakos
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Perhaps you should stick to posting "facts" about your own engine? Except that so far we've seen no evidence that you actually have one...
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Manolis: you are wrong. :D You are assuming I have a flat piston...:rolleyes: Without head/piston volume ratio and design you are guessing. :confused:
Maths doesn't lie.....it depends on if the person actually using it, whether they understand what they're doing or not.
So you're not so smart with your spreadsheets and formulas are you? :p
From your understanding, I know you have never built or modified a real engine ever!
To properly calculate the compression ratio you need to know:
Displacement;
Number of cylinders;
Non-zero deck volume;
Piston dome/Valve relief volume;
Head gasket volume;
Head Flycut volume;
and
Combustion chamber volume.
[URL="http://www.ugs.com/CaseStudyWeb/dispatch/viewCaseStudy.html?id=203"]UGS Article on the X4[/URL]
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Revetec wrote:
“Manolis: you are wrong. You are assuming I have a flat piston... Without head/piston volume ratio and design you are guessing.
Maths doesn't lie.....it depends on if the person actually using it, whether they understand what they're doing or not.
So you're not so smart with your spreadsheets and formulas are you?
From your understanding, I know you have never built or modified a real engine ever!
To properly calculate the compression ratio you need to know:
Displacement;
Number of cylinders;
Non-zero deck volume;
Piston dome/Valve relief volume;
Head gasket volume;
Head Flycut volume;
and
Combustion chamber volume.”
As long as you follow the conventional definitions for the compression ratio, I do not need (for the calculations of my previous post) to know neither the shape of the piston head nor the shape of the combustion chamber.
And it does not matter if the piston is flat or not.
If the dead volume is Vd and the Bore B, the equivalent height is defined as D=Vd/(pi*B*B/4).
The only assumption I did is that the gasket hole has diameter equal to the cylinder bore. As long as this is true (as in every other engine) what I wrote:
“Either it is a super-over-square cylinder with 118.5mm Bore for 54.4mm Stroke, or the data given about the gaskets and the compression ratios are wrong.
Mathematics cannot lie.”
is the case.
Recheck your data.
Thanks
Manolis Pattakos
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You're wrong again.
I'll give you an example:
If I had an engine with 9:1 compression ratio, and put a high top piston in it and changed the compression ratio to 10:1. The engine capacity is the same, the head gasket is the same thickness. So you cant work it out.
The only way is to know the requirements for working it out that I posted.
Go back to engine school.
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[QUOTE=manolis;675046]"Mathematics cannot lie.” [/QUOTE]Who told you this? Mathematics can say anything you want it to. Math is a simplification of the "real thing" it is NOT the real thing. Lets say I did a proof using Newtonian physics for the orbit of mercury. Then when data showed my predictions wrong I said "mathematis cannot lie." Well the math itself is not wrong but rather the assumptions under it. Relativity is necessary to calculate some things.
Similarly, when you claim to determine the dimensions of someone else's engine by assuming its the simplest possible design, you make a fool of yourself. When you try to "prove" that your engine is perfectly balanced without taking the second or higher order vibrations into account and without using any kind of real modeling, you make a fool of youself.
Sure your math is good. Congratulations on passing 8th grade geometry.
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Compression ratio is calculated by (we use this formula when buildng our Type 1 engines with flat top pistons):
(Head cc + Deck cc + 1 Cylinder volume) ÷ (Head cc + Deck cc) = Compression Ratio
Total Displacement:
BORE (mm) X BORE (mm) X STROKE (mm) X 0.0031416 = Engine Displacement in CC's
Your calculation is nothing more than a GUESS (I know what the stroke & bore is).
What did you work out the head cc is?
What did you work out the deck cc is?
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[quote=shane_trikes;675515](I know what the stroke & bore is)?[/quote]damn you !!! THe rest of us only know 50% of that .....
...... the BORE ( in this thread ) :D
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[QUOTE=Bob;675418]Who told you this? Mathematics can say anything you want it to. Math is a simplification of the "real thing" it is NOT the real thing. Lets say I did a proof using Newtonian physics for the orbit of mercury. Then when data showed my predictions wrong I said "mathematis cannot lie." Well the math itself is not wrong but rather the assumptions under it. Relativity is necessary to calculate some things.[/QUOTE]
a great example of maths lying is taylor series, its an approximation not exact. much of engineering is simplification and moddeling of an ideal situation. Funny thing is maths is usefull when it lies.
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[QUOTE=jediali;675537]a great example of maths lying is taylor series, its an approximation not exact. [b]much[/b] of engineering is simplification and moddeling of an ideal situation. Funny thing is maths is usefull when it lies.[/QUOTE]
I would argue that should read: [quote][b]all[/b] of engineering is simplification...[/quote]
I think you would be hard pressed to find any model of a real system that is [U]perfectly[/U] accurate, much less a highly complex system with dependency across multiple physics disciplines.
My friend once told me “the real world never lies” and that is possibly the best engineering advice I have ever gotten.
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According Revetec’s X4 specifications:
“Some of the X4 Engine Features:
. . .
9:1 compression ratio (1.6mm head gskt) Current;
9.5:1 compression ratio (1.2mm head gskt);”
There is no mention for piston replacement / different pistons.
For any other engine these specifications just say that reducing the head gasket height from 1.6mm to 1.2mm, the compression ratio changes from 9:1 to 9.5:1.
Revetec wrote:
“I'll give you an example:
If I had an engine with 9:1 compression ratio, and put a high top piston in it and changed the compression ratio to 10:1. The engine capacity is the same, the head gasket is the same thickness. So you cant work it out.”
When the “high top piston” of Revetec’s example replaces the normal piston of X4, the compression ratio becomes 10:1.
In order to reduce the compression ratio back to the initial 9:1 we can:
either use a thicker head gasket, with gasket height (1.6+x)mm,
or remove some material from the cylinder head keeping the 1.6mm head gasket unchanged.
With the “high top piston” in the X4 / 9:1 compression ratio engine, the reduction of the height of the head gasket for 0.4mm gives a new compression ratio of 9.5:1, in both cases.
In the first case the gasket will have a new height of (1.6+x-0.4)mm.
In the second case the head gasket will have a height of 1.2mm.
I.e. neither the shape of the piston crown nor the shape of the combustion chamber play any role in the calculations.
Thanks
Manolis Pattakos
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Shane Trike wrote:
“Compression ratio is calculated by (we use this formula when buildng our Type 1 engines with flat top pistons):
(Head cc + Deck cc + 1 Cylinder volume) ÷ (Head cc + Deck cc) = Compression Ratio
Total Displacement:
BORE (mm) X BORE (mm) X STROKE (mm) X 0.0031416 = Engine Displacement in CC's
Your calculation is nothing more than a GUESS (I know what the stroke & bore is).
What did you work out the head cc is?
What did you work out the deck cc is?”
The “Total Displacement” formula is correct only for 4 cylinder engines.
In the rest cases the correct Total Displacement formula is :
(number of cylinders/4) x BORE (mm) X BORE (mm) X STROKE (mm) X 0.0031416 = Engine Displacement in CC's
In the “Compression Ratio” formula, the ( Deck cc + Head cc ) is called the Dead_Volume cc.
Changing the head gasket from 1.6mm to 1.2mm:
The 1 Cylinder volume remains unchanged.
The Dead_Volume is reduced by the Dead_Volume_Diff cc quantity.
The Dead_Volume_Diff cc equals to :
Dead_Volume_Diff cc = BORE (mm) X BORE (mm) X 0.4 (mm) X 0.0031416 / 4
(1.6mm –1.2mm = 0.4, and the dead volume decreases – with the new 1.2mm head gasket – as much is the volume of a cylinder with diameter the gasket hole diameter – which equals to the Bore - and height the reduction of the gasket height).
1 Cylinder volume = BORE (mm) X BORE (mm) X STROKE (mm) X 0.0031416 /4
So, the ratio of the (DEAD_Volume_Diff cc) to the (1 Cylinder volume) is:
Dead_Volume_Diff cc / 1 Cylinder volume = 0.4 (mm) / STROKE (mm),
i.e. 1 Cylinder volume = Dead_Volume_Diff cc * ( STROKE / 0.4 (mm) )
and so STROKE = 0.4 mm * 1 Cylinder volume / Dead_Volume_Diff cc
9:1 is the initial compression ratio (with the 1.6mm head gasket), according X4 Revetec specifications, so:
(Dead_Volume cc + 1 Cylinder volume) ÷ (Dead_Volume cc) = Compression Ratio = 9.0
This is equivalent to:
9.0*(Dead_Volume cc)=(Dead_Volume cc + 1 Cylinder volume)
which is equivalent to:
1 Cylinder volume = 8.0*(Dead_Volume cc), i.e. the volume of the cylinder is eight times the Dead_Volume.
But 1 Cylinder volume is 2400 cc / 4 = 600 cc, so Dead_Volume = 75 cc.
Replacing the 1.6mm head gasket with the thinner one of 1.2mm, the compression ratio goes from 9:1 to 9.5:1 according Revetec’s X4 specifications. The dead volume is now ( Dead_Volume cc – Dead_Volume_Diff cc ), so, according the Compression Ratio formula we have:
(Dead_Volume cc – Dead_Volume_Diff cc + 1 Cylinder volume) ÷ (Dead_Volume cc – Dead_Volume_Diff cc) = New Compression Ratio = 9.5
This is equivalent to:
9.5*(Dead_Volume cc – Dead_Volume_Diff cc)=(Dead_Volumecc –Dead_Volume_Diff cc + 1 Cylinder volume)
and replacing the (1 Cylinder volume) quantity by the 8.0*(Dead_Volume cc) as calculated previously, the last equation becomes:
9.5*(Dead_Volume cc – Dead_Volume_Diff cc)=(Dead_Volume cc –Dead_Volume_Diff cc + 8.0*(Dead_Volume cc))
which is equivalent to:
0.5*Dead_Volume cc = 8.5*Dead_Volume_Diff cc
which is equivalent to:
Dead_Volume_Diff cc =(1/17)*Dead_Volume cc =(1/17)*75 cc = 4.41 cc
The stroke was calculated previously as
STROKE = 0.4 mm * 1 Cylinder volume / Dead_Volume_Diff cc
so
STROKE = 0.4 mm * 600 cc / 4.41 cc = 54.4 mm
The Total Displacement formula gives :
(number of cylinders/4)*BORE (mm) X BORE (mm) X STROKE (mm) X 0.0031416 = Engine Displacement in CC's, i.e.
(4/4)*BORE (mm) x BORE (mm) X 54.4 (mm) x 0.0031416 = 2400 cc,
i.e. BORE *BORE =14043.05, so the bore is : BORE = 118.5 mm
As you see, there is no “GUESS” in the above simple calculations.
Do you know a third part to pay to prove me wrong?
As you see, the third party was not necessary to verify the absolute balancing (as absolute as the Wankel Rotary engine) of the GRECOi3.
What I wrote and repeat here is:
Either the bore x stroke is 118.5mm x 54.4 mm or the specifications of X4 are not correct as given.
It seems that what I had to go through, until to convince for the absolute balance of the GRECOi3, I have to go through again to prove the obvious (interrelation of gasket height and compression ratio).
Looking back, it is more funny.
I had to use the most stupid argument, ever : the divided balance webs covering less than 180 degrees around the shaft.
Where mathematics, physics, geometry and trigonometry failed, this stupid argument finally worked.
In any case, what counts is that now the GRECOi3 has the “certificate” of being the only three cylinder reciprocating engine as perfectly balanced as the Wankel rotary and the best conventional V12.
Thanks
Manolis Pattakos
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It was written:
“When you try to "prove" that your engine is perfectly balanced without taking the second or higher order vibrations into account and without using any kind of real modeling, you make a fool of youself.
Sure your math is good. Congratulations on passing 8th grade geometry.”
It is as wrong as it gets.
The inertia forces, inertia rocking couples and inertia torques of the GRECOi3 have been calculated taking into consideration EVERY order of vibrations and not only the first order.
As shown in the relevant excel, the cams on the two counter-rotating shafts have profiles that provide pure sinusoidal (of first order) piston travel versus shaft angle. The formula for the geometric construction of such cam lobes is in the pattakon web site (when I add links or plots they are deleted, so search).
We start with cam-lobes providing pure sinusoidal piston motion.
Then the excel spread sheet, based on the piston travel and the revs, calculates the piston speed (which is also pure sinusoidal of first order).
Then the excel spread sheet, based on the piston speed calculates the piston acceleration (which is also pure sinusoidal of first order).
Then the excel spread sheet, based on the piston acceleration, calculates the inertia force necessary to be applied on the piston to cause the calculated piston acceleration (again pure sinusoidal of first order).
Then it is calculated the sum of the inertia forces from the three reciprocating pistons (120 deg phase difference from piston to piston). Sum: absolutely zero.
Then it is calculated the inertia rocking couple due to the offset of the pistons. It is again a pure sinusoidal of first order.
Then it is calculated the inertia rocking couple from four balance webs secured on the counter-rotating shafts. It is also a pure sinusoidal of first order.
Then the sum of the rocking couples is calculated and is absolutely ZERO.
The higher order vibrations are not “simplified”.
In the balance calculation of the GRECOi3 any order of inertia vibration is taken into consideration.
The higher (than first order) vibrations do not exist.
The architecture of the GRECOi3 does not generate such vibrations.
This is why I keep saying that only Wankel rotary and some good conventional V-12 can compare to the perfect balancing of the GRECOi3.
All the GRECOi3 vibration analysis is based on simpler than 8th grade geometry.
I try to understand why everybody is so much confused with so simple things.
You have the posts, you have the links, you have the plots. Read again and again. The balance program is invaluable for such study.
Thanks
Manolis Pattakos
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Manolis , as was said before ... stop kidding yourself with the excel simplifications. Get a decent analysis done and you'll perhaps realise why rotating and reciprocating REAL WORLD objects cannot be "based on simpler than 8th grade geometry".
You've read too many books and think the world is that simple :(
Nobody here is confused. You are as you lack engineering background to realise how inane your comments are.
You're simple math is not considering tolerances - nothing can be a perfect fit - nor material twists.
So you are 100% wrong in claiming that the higher order have been considered and don't exist.
It's THAT simple... so hence none of your other "facts" can be relied on. Sorry, go back to school.
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[QUOTE=manolis;675919]
What I wrote and repeat here is:
Either the bore x stroke is 118.5mm x 54.4 mm or the specifications of X4 are not correct as given.
[/QUOTE]
for everybody else following this thread, Manolis's calculation of the X4's bore & stroke is wrong.
I looked through your calculations and I immediately picked out one of YOUR incorrect assumptions.
Hey Matra, I hope Brad can spice up this thread and break the boredom with some new data shortly. We have a new trike waiting for the X4 once it has finished its dyno testing phase.
We are looking forward to the duration testing phase, Cairns to Alice Springs (Ayers Rock) upto Darwin, back through Mt Isa back to Cairns (just one leg). This will see long periods of wide open throttle and extreme conditions. This sort of trip would be around 10,000km. Unfortunately (unconfirmed yet) that the Northern Territory Government have now imposed a speed limit on all highway's so we will have to ride at a reasonable speed (this highway was used for one of the Cannonball Run race series).