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Causes of inefficiency in engines

  1. Aug 20, 2011 #1
    What causes inefficiency in diesel or Otto engine? the publications do not explain and University professors could not explain realistically, so engines are as inefficient as were in XIX century, because nobody knows how to remove the inefficiency causes. I expect the those hide in poor design and blame wrong trend of research for inability to find flaws of design.

    Modern engine does not exists as all those are invented in XIX century and are very inefficient, so claiming "Highly efficient or modern diesel engine is misleading and dishonest.

    The current trend of research resulted in improving rethorics, but engines. I suggest leaving rethorics to English teachers and end dishonest misleading. The efficiency below 50 % is a huge inefficiency and nobody knows what causes that in combustion engines. Without finding the causes one cannot improve engines.
    Last edited: Aug 20, 2011
  2. jcsd
  3. Aug 20, 2011 #2


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    You make a couple of hasty generalizations about modern engines and conclude that no progress has been made in efficiency in more than 100 years of engine development.

    The primary reason IC engines do not operate at relatively high thermal efficiencies is due to the fact that their maximum operating temperature is limited by the materials used in their construction. If steel or cast iron did not melt, then higher operating temperatures could be used and higher thermal efficiencies would naturally follow.

    To say that a diesel or gasoline engine produced in 2011 is just as efficient as one produced in say 1900 betrays a lack of knowledge of engine development over the past century. Large slow speed diesel engines, such as those powering ships, have thermal efficiencies approaching 50%, and this is quite an improvement over the crude prototype engine which Diesel himself built to prove his ideas about how IC engines could be improved.
  4. Aug 20, 2011 #3
    I'm no expert, but friction for starters. There's alot of moving parts rubbing against each other that create inefficiency. That said, the quality (and weight) of materials used in building as well as lubricating the engine has improved over the years leading to increases in efficiency. Compression also has a great impact on efficiency (which is why diesels are more efficient than gasoline engines). Better fuels and a better understanding of the details of engine building has resulted in increases in compression.

    Besides that, the engine has to power its cooling, lubricating and electrical systems which eat up efficiency, not to mention the pumping losses of sucking and exhausting air to/from the engine which can eat up a large portion of efficiency. Again, advances in understanding and streamlining these systems has increased efficiency. To improve airflow through the engine, for example, it's not enough to simply round off the corners. You need to perform expensive tests to figure out the best profile for the airflow, and I'm sure advances in computers have greatly eased this process and led to increased efficiency.

    Then there's the fact that engines have to operate at a wide range of loads and rpm. An engine will be most efficient at only one point and inevitably will suffer losses at other points. Just the fact that the gas pedal is not all the way to the floor eats up efficiency (although might increase gas mileage). Steady state engines such as generators generally have higher efficiency, and hybrid engines can be more efficient for this reason.

    Ultimately the efficiency is limited by the difference in the hot and cold reservoir...that is, how hot the engine runs and how cold the outside air is. The bigger the difference, the higher the possible efficiency. Advances in metallurgy and otherwise have allowed for higher operating temperatures.

    Emissions control eat up efficiency...

    Waste heat...the engine will heat up, the components will heat up when running, and that all gets dumped out into the atmosphere without doing useful work. Everything ultimately ties in with cost. There are ways to recover some of the waste heat, with turbines in the exhaust for example, but depending on the cost of fuel it apparently isn't worth the effort.

    I haven't checked the numbers, but I can't agree with you that today's engines are no more efficient than the ones in XIX century.
  5. Aug 20, 2011 #4
    There are no modern engines except one that is named a gun-engine! Diesel was invented in XIX century and cannot be modern in XXI century.

    Efficiency below 70 % is very poor efficiency, yet in your car the efficiency is much lower. In addition every engine has three distinctive speeds: speed of highest torque; speed of highest power and another of highest efficiency, but during routine street driving the average efficiency is lower than 7 % while during starting hardly exceeds ).5% and that destroys the environment and pockets of truckers. The use of words "modern and highly efficient diesel engine" is misleading and also dishonest.

    Causes of the inefficiency that first appeared in Otto engine patented in 1876 have been handed down from generation to generation unnoticed by researchers mainly preoccupied with improvements of parts and prevention of detonations of fuel and these still penetrate into engines under development for the future; that is because the causes relate to very poor design.

    Physics teaches that to maximize:
    1. the torque max pressure should act on horizontal crank, but in diesel it acts on crank aligned with centerline of cylinder;
    2. use of fuel the energy release from fuel must be fast as power available from fuel is defined as energy released in time, but in diesel engine it is very slow and lasts up to 60 degree of crank move;
    There are 20 causes of inefficiency directly related to outdated XIX century design. The inventor of gun-engine has spoted all 20 and eliminated them, thus the gun-engine preserves high efficiency 445.6% higher than that of "Modern engine" you referred to.

    A new XXI century thermodynamic cycle from which resulted a new engine design has been published recently. Also a Suzuki engine has been converted into XXI century engine according to new engine design.

    As new engine detonates vaporized or gaseous fuel, which creates much higher pressure than max pressure allowed in Suzuki cylinder, the inventor lowered fuel supply to negligible 10% of originally intended to prevent cylinders from bursting. Nonetheless the power output was 40% higher than max power of the original Suzuki that was fully fueled. That is what I call modern and highly efficient gun-engine.

    You could brag that ...or you can buy a license to produce gun-engine and make yourself a multi-billionaire. It is up to you to stay in XIX century or jump directly into XXI century technology.
  6. Aug 20, 2011 #5
    You asked what causes inefficiency in engines, but you obviously know full well what it is! Had you been clearer with your agenda, I could have avoided writing up my dissertation and being made to feel a fool, and gotten on with drinking my beer.

    Powodzenia z kanonierką!
  7. Aug 20, 2011 #6
    Thermodyamic efficiency and mechanical efficiency are two different things. Anyone claiming efficiencies close to or higher than the carnot efficiency is talking a load of excrement.

    I'd buy that for a dollar.
    Scam, so IBTL.
  8. Aug 21, 2011 #7

    Ranger Mike

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    Kaziczek you are not a serious person..do not waste my time.
  9. Aug 21, 2011 #8


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    Study a bit of thermodynamics, and then come back and answer your own question.
  10. Aug 21, 2011 #9
    Inventor of gun-engine has created a new thermodynamic cycle free from flaws of Diesel cycle (and that is a new knowledge you cannot find in books), from which huge intentional losses of heat to cool diesel engine and prevent diesel from efficient operation, have been eliminated. The trick is to expand exhaust completely as expansion produces work and cools cylinder internally. But diesel engine cannot expand completely thus only partially convert heat into work and not converted part of heat accumulates in parts, so if not disposed melts engine.

    This is the major fault in diesel engine, because cooling wastes most of energy released from fuel. To correct that a new thermodynamic cycle was invented. The gun-engine does expand exhausts below atmospheric pressure and does that more than once, so more than one power stroke (up to six) results from each energy release from fuel; thus the exhaust cools exclusively by expansion below 140 F degree (60 C degree) and no need for radiator! In this way the gun-engine efficiency is comparable to that of Carnot engine and that is new thermodynamics that works perfect. While diesel engine efficiency is less than 4 times lower that Carnot cycle efficiency. Tests of Suzuki engine converted according to new design proved efficiency has increased by 445.6%.

    The nonsense, you cherish so much, has been created by those who wasted $billions of grant money to excuse lack of results. I admire those who created thermodynamics, because thermodynamics is about energy on atomic level and creators of the thermodynamics had not even expected that atoms exist.

    By the way Max Plank had combined operation of Heat pump with heat pump and proved mathematically that the combination is more efficient than Carnot engine alone. The inventor of gun engine found that combining operation of a gun with diesel engine boosted the efficiency by 445.6% over the efficiency of diesel engine alone. The difference between both ways is that Plank's combination was theoretical and the combination proposed by inventor of gun-engine is practical.
    Last edited: Aug 21, 2011
  11. Aug 21, 2011 #10
    One reason is having very short time to burn the air/fuel mixture.
  12. Aug 22, 2011 #11
    Sounds clever, but due to the nature of your idea, it'll only move backwards by talking about it. Build it first, then show off the performance data. Prepare to become richer than God!
  13. Aug 22, 2011 #12
    It was already done! Now is time to tell about it, but slaves of ordinary thinking crowding positions in Universities and industry ...
  14. Aug 22, 2011 #13
    Guys, have a read through this before dismissing the claim:

    << Link to crackpot paper deleted by Moderator >>

    Cross-section view at the end of the article; have a look at that first.

    Interesting concept once you get past the rhetoric.
    Last edited by a moderator: Nov 7, 2013
  15. Aug 22, 2011 #14
    Internal combustion engines are only 20% efficient. 80% of it's efficiency is lost through things like heat and friction.
  16. Aug 22, 2011 #15
    400% or 40%? Why don't you provide more data? I looked at the article posted by Mender and it lacks testing data. Or are you trying to hide the results? People will assume you misread your instruments, which is possibly what happened.
  17. Aug 22, 2011 #16
    It was 15 pages long and was about causes of the inefficiency and how I eliminated them. Description of the experiment would take at least another 15 pages and I do not really care, if you believe me or not. I'm not the God! Nor is my engine. We do not require believers! We prefer those who can understand, because such could advance my idea further. The rest is not important. I believe that one can make science by creating new knowledge, which advances technology. Engines were bad by design for over century. I just shown that could be better by design and I did it with a budget not exceeding $100 and time less than 10 min. This is my satisfaction that you a career guy would never understand.

    It was 40% higher power output while fuel consumption was 15 times smaller which translates in 445.6% better performance. In addition that increases average travel on tank of fuel 15 times. If you know how the average efficiency through streets affects vehicle with diesel engine you should calculate that easily!
    Tip diesel engine has efficiency 0.5 % at starting which increases to no more than 20% to 25% at 80% of max speed and lowers to 15 % at max speed, while gun-engine preserves high efficiency from start up to max speed and in addition can be directly clutched to wheels, while diesel engine need torque boosting transmission that consumes energy. If you ever were involved in engine tests you should know that.
    Last edited: Aug 22, 2011
  18. Aug 22, 2011 #17
    Why are you posting about it? You had an achievement, now it's in the past. You can bury it and move on to something else. Right? Or do you want to take it further? With the help of other people? To get anybody valuable on board you'll need to show something convincing.

    I think you're afraid to reveal the details because people will find faults in them. And they will, but you'll only gain from understanding the problems instead of hiding them. It's hard to make any technological advancements in isolation. You need communication with others in the field to avoid getting trapped in a dead-end like Diesel's failed engine. That only became successful after other people discarded some of his ideas.
  19. Aug 22, 2011 #18
    Am I wasting my time by explaining obvious things to a slave of ordinary thinking???
  20. Aug 23, 2011 #19
    Clearly you didn't get 450% efficiency gain compared to 25% stock. So what did you actually do? Once you reveal the details you'll also reveal the faults and can go back to test more properly.
  21. Aug 23, 2011 #20
    I want data, not words asking for faith!

    By the way, this thread may get locked soon. You should post on a less professional forum.
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