Messerschmitt seemed to see the arrival of the jet age, and said excitedly: "Philip, I can't see through you more and more!" The success of the assault rifle can also be said to be that you have worked in Krupp for several years, and the torque conversion propeller, turbocharger and this jet engine, it seems that even I, the chief designer of the aircraft manufacturing company, dare not imagine, but let you do it! I'm even beginning to wonder if you're a messenger from God! As he spoke, Messerschmidt looked at Philip repeatedly.

The rest of the people were also staring at Philip curiously, and the shock in their hearts was even worse, this young man actually knew a lot more about aviation technology than them, how could this not make them feel both shocked and envious!

Philip was furious at these glances, and secretly said that they wouldn't dissect me as an alien, would they? It seems that I have to be a little more restrained, and I can't let too advanced technology appear in this world, otherwise it will be messed up. Fortunately, the jet engine is something that has already been worked on, and it is not too bizarre, but it is just possible to get it out earlier.

Philip coughed lightly twice, and said embarrassedly, "Don't look at me like that!" I'm not a monster, I just read more and do more. Now that you have seen what a jet engine is, we want to develop this kind of engine, so that the names of BFW and Dragon Soul Aircraft Manufacturing Company can be heard all over the world, and so that all aircraft manufacturers in the world will come to buy our engines, how good would it be? ”

When everyone heard this, they were even more excited and applauded vigorously. Philip also saw that this jet engine is not generally attractive to engineers, you must know that as an aeronautical engineer, it is already very remarkable to be able to participate in the development of an aircraft or engine with the world's advanced level, not to mention the development of an unprecedented power system, which may become the power system of the aviation industry revolution, how can they not be excited!

Billy's neck flushed with excitement, and he said loudly: "Mr. Philip, then tell us about this jet engine, what is its principle and structure!" ”

Philip looked at everyone, only to see that everyone stretched their necks, waiting for his answer, and then said calmly: "Jet engine, also known as aviation gas turbine engine." Compared with the piston engine, it is very simple in structure, except that the rotating compressor and the turbine are connected on the same shaft, and a combustion chamber is installed between the two, and the air is continuously sucked into the compressor, and after compression and pressurization in it, it enters the combustion chamber and injects oil to burn into high-temperature and high-pressure gas, and then enters the turbine to expand and do work. Obviously, the expansion work of combustion must be greater than the compression work required for the air to be compressed in the compressor, so that the surplus work can be utilized. This part of the surplus work can be exported to the outside world and used as the power of the aircraft. The high-temperature and high-pressure gas is rapidly sprayed backwards to generate a huge thrust to propel the aircraft forward. ”

"The gas expands and accelerates in the tail nozzle and is sprayed at high speed to the rear, creating a reaction thrust. Under the same gas generator conditions, some or most of the available work at the outlet of the engine's combustion chamber can also be converted into shaft work through the power turbine. Shaft power drives the propeller, so that it becomes a turboprop engine, at a lower flight speed, the jet engine propulsion efficiency is low, and as a propeller has a high propulsion efficiency when flying at low speed, the turboprop engine combines the advantages of jet engine and propeller, is the best solution to replace the piston engine. ”

When Philip finished speaking, the engineers immediately understood the reasoning, and Messerschmidt asked: "Just now you said that the British are developing centrifugal jet engines, and you are demonstrating axial jet engines, so which design is more reasonable?" ”

Philip said seriously: "Mr. Messerschmitt is a good question. Both designs have their own advantages and disadvantages, but which way should we go? The centrifugal jet engine is to use centrifugal force to throw the gas around and compress the gas, the centrifugal jet engine has a simple structure, low technical requirements, but low efficiency. In the axial flow type, multiple turbine wing fans press the air in front of the combustion chamber and ignite it. This internal structure is more advanced and practical. Although it is more difficult to develop axial jet engines, the mainstream of jet engines in the future will definitely be axial! ”

Billy asked excitedly: "Mr. Philip, this kind of jet engine should have very high requirements for structural materials to withstand the force of high temperature and high pressure gas, can we find these materials?" ”

Billy is an expert in aero engines and knows a little about jet engines, so his questions are very practical.

Philip nodded and said: "Yes, in terms of high-temperature materials, it needs to be able to withstand high-temperature heat-resistant alloy materials above 600 °C, and the high-temperature, high-pressure, high-speed gas flow from the combustion chamber can only be converted into a form that can be used by jet engines by doing work through impact turbines." Compared to compressors, turbines need to add a very important performance, and that is high temperature resistance. In order to ensure that the turbine material is not melted by high-temperature gases, the turbine must be cooled by complex means, such as air film cooling, impact cooling and convection cooling. These means of cooling are achieved by the cold air released from the inside of the hollow turbine. The need to cast hollow turbine blades with complex aerodynamic shapes has become a major challenge for the aviation industry. ”

Billy opened his mouth wide and said, "Ah, it's so hard! So is there any hope for us? ”

Philip said with a smile: "I think there shouldn't be much of a problem, our Dragon Soul Aircraft Manufacturing Company has successfully developed several high-temperature, high-strength aluminum alloys, and jointly produced them with Bofors Company." In terms of alloys, Bofors also has a high level of technology and believes that it can complete this task. ”

Messerschmidt asked: "And what about turboprops?" ”

Philip said calmly: "To transfer the power of the turbine to the propeller, you also need a set of shifters. In fact, turboprop engines are more efficient than turbojet engines, which cause high speeds at the end of their blades, which can generate shock waves. In addition, because the turbine rotates very fast, there must be a variable speed gear between the turbine and the propeller to reduce the speed of the propeller so that the blade end does not exceed the speed of sound. So an aircraft with a propeller engine will weigh more than one gear. However, in general, the turboprop engine still has its superior side, for example, the fuel consumption is much lower than that of the jet engine, even close to the piston engine, and the transmission gear can be reduced as much as possible, so in general, it is still very suitable for assembly on bombers and transport aircraft. It has the advantage of having more power and flight speed than an aircraft equipped with a piston engine, while the fuel consumption is not much different from that of a piston engine. ”