Chapter 2549: The collision of wisdom three

"Of course, in fact, the Seaiv aircraft is just a compromise between ideals and reality, because we have to use the engines produced in France, which determines that my aircraft can only use second-rate engines. Secondly, because of the engine damage in the war. Because of this, I can only choose to use an air-cooled engine instead of a liquid-cooled engine. However, it was enough when it first appeared."

"In terms of power selection, there is a half-grade gap between us and the top level. However, in fact, I have never given up the pursuit of the most cutting-edge aviation performance. In the design of the seav aircraft, I plan to adopt the British. Eagle liquid-cooled engine, and in order to adapt to this engine, my team and I optimized the shape and structure of the entire aircraft. It was originally prepared to deal with your country’s later more advanced aircraft, but the war ended. Can only stay in the prototype stage forever." Marcel said with a sigh.

　　 "So, now you are going to use Daimler-Benz engines to revive him?" Henkel asked.

　　 "Well, yes, if I can, I also hope that this bidding can revive my factory." Marcel said.

　　 "Then it depends on your ability. By the way, whether it is the Bavarian government or giants such as Junkers and Fokker in this bid, they will come up with new products of their own." Henkel said.

　　 "In addition, I would like to ask, has your country discovered that the use of gasoline from different origins will cause a large gap in the flight performance of the aircraft?" Marcel asked.

　　 "Can you tell me more in detail?" Henkel asked.

"Of course it can. For example, when our aircraft uses domestic fuel, it is prone to knocking. You and I know that under normal circumstances, the operation of the cylinder should be like this. With the push of the piston, the cylinder The internal air and gasoline mixture begins to compress. When it reaches a certain level, the spark plug starts to ignite. At this time, the gas ignites and expands to work. This process starts from the spark plug and then diffuses to the surrounding. But sometimes, when the piston moves to the ignition point Before, the oil and gas mixture inside the engine would ignite ahead of time! However, it caused the cylinder to vibrate. In the light of this, the output power of the engine was affected, and in the worst, the engine was scrapped.” Marcel said.

　　 "We have also encountered this problem. Generally speaking, it should be a fuel problem." Henkel said. "Our engine rarely happens at low compression ratios, but it is more common in certain models with high compression ratios. For this, we must add something."

"Yes, when the compression ratio is low, this problem is not obvious, but when the high compression ratio is used later, the problem is more serious. At present, the only thing the French Air Force can do is to use when high power is required. It is possible to inject a mixture of water and methanol into the cylinder, but this problem is just an idea and has not been completely solved." Marcel said.

　　In fact, the so-called engine knock problem was discovered very early in history, and for this reason, engineers also used high-speed cameras to observe the process and causes of knock. Then why did people measure the anti-knock performance of gasoline and specifically put forward the so-called octane number concept, and what does this concept mean? In other words, a mixture of n-heptane and isooctane is used to describe the anti-knock value of gasoline. As for why these two substances were chosen instead of others, the reason is simple. The volatility of these two substances is similar. No matter how they are mixed, the ratio will not change.

　　 That's great, what does the so-called No. 87 fuel in history mean? This means that the anti-knock ability of this gasoline is the same as the mixture of 87% isooctane and 13% n-heptane, so the larger the proportion of isooctane, the better the anti-knock effect. It also means that the fuel performance it represents is better.

　　 Now the question is, how did the so-called No. 130 fuel in the war come out? After all, it is only 100 when it is completely octane! The reason is simple, add anti-knock agent to improve it! In fact, what the so-called No. 130 fuel represents is no longer the so-called isooctane ratio. In history, the best additive that appeared before World War II was the tetraethyl lead series.

　　 It’s so good. Maybe someone will ask, why does the addition of water and ethanol stop knocking? The reason is simple. Adding a mixture of water and ethanol will cause the temperature to decrease. One of the reasons for knocking is that the temperature and pressure cause premature combustion. On the other hand, ethanol has better anti-knock performance, while water vapor is It won't knock... So after adding ethanol and water, the anti-knock performance of the mixture in the cylinder will naturally be greatly improved!

However, for the current plane, both Germans and Americans have not evolved to the point where they have begun to use various additives to improve fuel performance~www.wuxiaspot.com~ even the simplest and crudest injection of water and ethanol mixture in later generations This kind of emergency solution was only thought of but not practiced. So what is the solution for each participating country? The Germans’ method is very simple, because they found that Romani’s fuel quality is relatively high, so they directly restricted the use of Romanian crude oil for aero engines and improved the refining level as much as possible. As for the Allies? The disposal method is also very simple, limit the power....... At a certain temperature and pressure, it will cause knocking, so just reduce the power?

"The use of a mixture of water and ethanol to improve temporary knock performance is only an emergency method. In fact, we should still improve the knock resistance from the perspective of fuel, so we are currently thinking of ways to synthesize some additives to improve this performance. . It just takes time and a huge investment." Henkel said.

　　 After the discussion was over, Henkel's evaluation of Marcel was still very high. After all, the latter did have very deep knowledge in aviation theory, and some methods were also very good. This is the most precious!

　　 There are also unique technical details. For example, the two large-caliber machine guns placed inside the wing that were later visited are specially installed with shock absorbers to reduce the impact of the vibration of the machine gun on the flight when shooting.

"Marcel Brocher is a very good aircraft designer. He definitely represents the highest level of the French aviation industry. If such a master can join the Bavarian aviation industry, it will undoubtedly be useful for our business. Very important role." Henkel wrote in a letter to the crown prince.

　　 The second one is more~~~! Please subscribe for a reward~~~! ! !