Engine guru Prof. Friedrich Indra: The combustion engine will live for a very long time!

Prof. Friedrich Indra relies on internal combustion engines

It was less about the past than about the future that our guest author Jens Meiners led with engine pope Professor Friedrich Indra. He criticizes the focus on the battery car and considers combustion engines to be sustainable for a very long time.

Indra criticizes and warns of a collapse of the auto industry: while the new purchases fail, the authorities also wanted car manufacturers to pay billions in fines. These threshold fines would have to be postponed. Politicians have now recognized their self-deception, says the motorist. Now she is looking for ways to save the face.

Professor Indra, you have just turned 80 and look back on six decades of development work on the automobile. What is the most important lesson for you?

Indra: What is most impressive for me is how the combustion engine has defied all hostility for over 100 years and has always been at the forefront of development. At the very beginning of automotive history there was an electric motor, the efficiency of which was significantly better. But if you include the energy transport, the batteries and all the associated factors, then it loses all advantages. That is why the electric motor disappeared as soon as the combustion engine could be started electrically.

Indra: Modern combustion engines are clean and efficient

I believe that the cremator will live for a very long time because it best meets people's desire for completely free, independent transportation. Anyone can afford a car with a combustion engine, they have all become very economical and clean, and so far all actions to remove him from the throne have fizzled out. Ultimately, the combustion engine with an electric starter is a technology that is over 100 years old.


There shouldn't be anything better?

Indra: Counter question: Do you think there is anything better than a bike? It was invented thousands of years ago, but despite all attempts, there is still no reasonable alternative.


Keyword Wankel engine?

Indra: The rotary engine, of course also a combustion engine, almost dug the reciprocating engine 50 years ago. That was a big mistake. The rotary engine would not have worked in terms of width due to its shape of the combustion chamber. An efficient engine must be capable of high compression; it needs a precisely defined, compact combustion chamber in order to be able to tease out the best efficiency from the fuel. In the rotary engine, this combustion chamber keeps shifting, you have to constantly heat new surfaces, and as a diesel it doesn't work at all. Nevertheless, Mercedes-Benz, for example, under the developer Wolf-Dieter Bensinger, was completely fixated on the rotary engine. I experienced this phase as a university student when I was allowed to design the V-belt for one of these motors. At the time, Bensinger was firmly convinced that the Wankel engine would prevail and therefore did not develop the reciprocating engine at all. This opened up a huge gap with BMW that could not be closed for many years. Because BMW didn't think much of the Wankel and diligently developed the reciprocating engine.


Were there not promising approaches with the two-stroke engine?

Especially the US manufacturers looked at this, most recently the orbital motor from the Australian Ralph Sarich. The two-stroke engine mainly fails due to its efficiency. He only got away well in racing because he was misclassified compared to the four-stroke, just like the Wankel, by the way. The variability that you absolutely need today can best be achieved with four valves that can be variably controlled, for example by turning the camshafts. With different strokes you can construct it very economically and very low in emissions. The two-stroke engine lacks this variability.


Could the gas turbine have been an alternative?

Indra: With its free combustion, the gas turbine actually has good exhaust gas behavior with little hydrocarbon emissions. But the response is so catastrophically bad that it could not prevail. A delay of several seconds doesn't matter on an airplane, but a machine in the car has to react immediately.


Will the gasoline or diesel engine win the race with the reciprocating piston engine?

Indra: Generally, it is a great advantage of internal combustion engines that they can run on a wide variety of fuels, whether gaseous or liquid. To your question: It depends on the cubic capacity. In ships and trucks, we are dealing with diesel engines, all four-valve made of high-strength gray cast iron. The gasoline engine would have a hard time in this class. But in a car with a displacement of up to two or three liters, the petrol engine can catch up with the diesel - with high compression ratios of up to 1:16, room ignition and reduced friction. We are talking about thermal efficiencies of 50 percent, and you can already see that the reciprocating piston engine has not yet reached the end of its development. There is also something else: with small cars, the cost of the engine plays a major role and the diesel is more expensive. In addition, you can design a car differently if you do without the diesel, you can save sound insulation and simplify the vehicle structure. In the larger engines, especially in the SUV, the diesel engine naturally remains dominant over the gasoline engine.


SUV, a nice keyword. Can you understand the criticism of these vehicle concepts?

Indra: The opponents of the car pretend that the auto industry has invented the SUV with bad intentions. But of course the industry only builds what customers want. In my last years at GM in the USA, I also drove SUVs, when the Europeans were still amused by this preference of the Americans. It is simply a more comfortable ride: with the classic bonnet you feel very safe, with the relatively steep A-pillars and the elevated seating position you can see out very well. And that explains the success of the SUV even in the relatively small vehicle classes.


If we think about small cars: Shouldn't we have to rethink city cars, perhaps as 500 or 600 kilos, whether with an electric motor or economical combustion engines? "

Indra: In principle, but you have to remember that something like this can only be a third car, not even a second car, an instrument for the rich people who already drive a Tesla. Otto normal consumers can not afford more than a car, for city, vacation, with surfboard or trailer, whether he is traveling alone or in groups of five. And he also wants to be able to sell it. And such a city car would never work for these people.


Can the hydrogen car succeed??

Indra: The hydrogen car is a much better solution for the customer than the battery-electric car, but overall I'm skeptical. It probably fails because of the infrastructure, and the overall efficiency is anything but advantageous. After all, the whole topic is supposedly about the environment.


How do you explain the criticism of the combustion engine that has been so irreconcilable for a long time?

Indra: I think this hatred comes from a time when dirt really came out of the exhaust, when the cars were still very loud. People often forget how dirty cars used to be, including the oil flags from the two-stroke engine. But the main criticisms have all been eliminated, today the engines are much cleaner and more economical, and that in much safer and more comfortable cars. Politicians have believed for decades that the combustion engine is coming to an end. When I was head of advance development at Opel in 1992, I was driving around with the interior minister Kanther in a large-scale electrical test on Rügen and he predicted at the time: "I bet with you, in 2000 ten percent of all cars would be electric". The current government, in turn, issued the slogan in 2010: by 2020 we will have one million electric cars. We are of course a long way from that, although the plug-in hybrids are now also counted as an electric car. Nevertheless, politicians took advantage of the diesel scandal and took the position: Now we no longer believe the industry, and now we'll tell you where to go, namely electrically.

The industry has tried several times to talk politicians out of this mistake, but it has been of no use because politics has only looked at the car and has not carried out a comprehensive assessment.


What will happen now?

Indra: The industry is heading for a catastrophe because the majority of customers do not want to buy electric cars. He is completely unsettled and will do the most obvious thing, namely to continue driving his current car. And that lasts, at least if it is a classic combustion engine, easily 10, 20, 30 or 40 years and more. The new acquisition cycle of seven to eight years, which is usually the case in the first energy crisis, will be interrupted because customers will keep their old cars and we will slide into a huge economic crisis. The capital invested can be used much longer in a classic car than in an electric car, whose battery will run out after around eight years and will no longer be renewed for cost reasons.


Don't you think you can get replacement batteries?

Indra: With an electric car, a battery costs half the new price! No dealer has such expensive spare parts in stock and certainly not the manufacturer. Once the first battery has been used up, i.e. if it has lost 20 to 30 percent of its capacity, the first customer will no longer invest half the original price in an old car. He certainly can't sell it anymore either. A temperature of 23 degrees and a low charge state would be ideal for storage. Any deviation from this reduces the capacity. At 45 degrees and medium charge, the battery lost 15 percent of its capacity after just two years. At even higher storage temperatures, a new battery can become unusable after only one year without being used even once. Of course, the whole thing also applies to e-cars that are on a heap. Like the VW ID3 now.


How can industry deal with this situation?

Indra: While the new purchases fail, especially in the current crisis, the authorities also want car manufacturers to pay billions in fines. This is how this industry breaks down. The only possible solution for me is: These fines are postponed. I know from many conversations that politicians have now recognized their self-deception and are now looking for possible ways to save faces. Some politicians are now demanding batteries that are light, cheap and last as long as a classic automobile, which is of course impossible. Others say the real problem is oil, which in turn opens the door to synthetic fuels. But the most important component will be to abolish e-mobility funding. Why should politics also promote technology that makes no contribution to climate protection?


Indra: Right now, in economically difficult times, almost all customers are showing the indispensable advantages that means of transportation with internal combustion engines have. And that under all climatic conditions, around the globe, on land, on water and also in the air. Together with further improvements and the new climate-neutral fuels, this will remain so for a very long time. Subsidies for e-mobility are now running out in China and the USA, and sales of e-cars are already sinking there. And VW's fate continues to be decided on the Golf, not on the ID3.

About Prof. Friedrich Indra: 1969 PhD at the Technical University of Vienna, from 1971 to 1979 at BMW-Alpina as Head of Development and from 1979 to 1985 Head of Engine Design at Audi; from 1985 to 1998 at Opel head of engine development and director of advance development; from 1997 to the end of March 2005 executive director of advance development at General Motors Powertrain in Detroit and member of the supervisory boards of the Pan Asian Automotive Center in Shanghai and the Metal Casting Technology in Milford. He has been a lecturer at the Vienna University of Technology since 1985, and in 1991 he was appointed honorary professor for internal combustion engines. (ampnet / jm)



1 comment to "Engine Guru Prof. Friedrich Indra: The combustion engine will live for a very long time!"

  1. Dear Mr. Prof. Indra, I would like to have your viewpoints on electromobility, efficiency vs. Internal combustion engines, simplicity in the construction of internal combustion engines and their idea of ​​the perfect and perfect internal combustion engine are discussed. Wasn't the 5-cylinder turbo-charged multi-valve engine in the Audi Quattro your development? I saw your interviews with Karsten Arndt Alte Schule on YouTube and I agree with many of your statements / views on current drive concepts. But I still can't quite understand your statements about the drive concepts. Not a word from them about gasoline extraction with its sometimes catastrophic pollution and the energy required to manufacture / transport it. Simply constructed engines are economical and efficient? (Ami?) Efficiency between electric and combustion engine? Many a staid electric car makes a technically sophisticated sports car look very old when sprinting from a standing start and doesn't even cost half the price. It is a shame that one cannot discuss these topics with you personally. MfG C. Bartel

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