Why do you two have to fight over this kind of thing? Zhang Lan suddenly sweated profusely: How long has it been an old rival, although Brother Zhu and Brother Tian are now in the same camp, but the idea of being stronger than the other party hidden in the bones of the two guys is lingering no matter what, and the idea of competing with their old opponents is hidden in the heads of these two guys all the time.

Well, no matter what the world thinks about the propeller fan, which can be called a new branch of the turbofan engine, or even because this kind of engine is too high and noisy, some people think that the propeller fan is just a short-lived project.

But Zhang Lan doesn't think so, and now experts believe that an aircraft equipped with a propeller engine is not as fast as an aircraft equipped with a turbofan engine, and the noise is louder than that of a turboprop engine, so it is not an ideal choice for an aero engine. Moreover, although the propeller fan engine is fuel-efficient, the turbofan engine uses more fuel than the propeller fan engine, which can be compensated for by the advantage of speed.

But Zhang Lan understands that although the propeller fan engine is not a suitable civilian engine project, there is no doubt about its use in the military, especially in large military or civilian transport aircraft, and with the passage of time, the fuel-saving effect of the propeller fan engine may not be very obvious now, but ten years later, when the international crude oil price exceeds 1 US dollar per barrel, the countries in the world with this research strength are crazy to study this speed faster than turboprop engines. However, it is not much different from the turbofan engine without afterburner, but the fuel consumption is only equivalent to that of the turboprop engine, which is roughly equivalent to about 70% of the fuel consumption of the turbofan engine - the savings are not fuel, it is all green dollars! Directly linked to your own wallet!

What they saw as a disadvantage at the beginning of the paddle engine has become a complete advantage for them as drugs are for addicts.

Looking at all transport planes in the world, whether military transport planes or civilian transport planes, from small transport planes to super-large transport planes, even the US C-"Galaxy" strategic transport aircraft and C-17 "Globemaster" with turbofan engines Although all of the world's famous transport planes, such as Russia's An-124 strategic transport plane and the Il-76 long-range transport plane, all use turbofan engines, all of these aircraft are high-subsonic aircraft, and none of them can fly at supersonic speeds.

Even the B-Stratofortress strategic bomber of the United States, which is equipped with eight turbofan engines, and the Boeing 747, which is equipped with turbofan engines, and other super-large wide-body passenger planes equipped with turbofan engines, have also flown at high subsonic speeds, and they have not exceeded the speed of sound.

From this point of view, in fact, if it is an aircraft flying at high subsonic speed between 700 km/h and 9C0 km/h, in the case of little difference in speed, the turbofan engine can be completely replaced by a more fuel-efficient propeller fan engine or turboprop engine, especially in the field of air transport that does not need to pay much attention to comfort, the use of paddle fan engine is very conducive to reducing transportation costs - the cargo on the aircraft will not dislike the noise of the propeller or propeller fan. The pilot is at the front of the plane, and the feeling is not very obvious.

Look at the United States, while developing turbofan engines, isn't it also vigorously developing turboprop engines and propeller engines at the same time? The C-130 "Air Hercules" medium-range transport plane, as well as its various variants and modifications, use turboprop engines, not that they do not want paddle fan engines, but that they have not made a major technological breakthrough in the field of paddle fan engines.

And the most important point is that the research of the propeller fan engine is still in its infancy even in the world, and the potential for technology development is very large, according to the results of theoretical calculations, under the condition of maintaining the existing flight speed and the same comparison of various aircraft conditions, the fuel consumption of the aircraft using the propeller fan engine can be reduced to at least 50% of the aircraft using the turbofan engine! Even lower than a turboprop engine!

Although this is only theoretical data, in practice is not very possible, but after in-depth technology development, Zhang Lan believes that the fuel consumption of the propeller fan engine is only about 60% of the turbofan engine is still not too much of a problem, and if the aircraft is designed to optimize the design of the aircraft's fuselage, the wing airfoil adopts a supercritical airfoil that is more suitable for high-speed flight, then the final speed of the aircraft reaches a cruising speed of more than 800 kilometers per hour. A top speed of more than 900 km/h should not be too much of a problem.

As for the noise of the paddle fan engine? with a savings of forty percent

Compared with the price of crude oil in ten years, it is a little louder than ever! Military aircraft and transport planes are not passenger planes, so what does it matter if they are louder? -- If in the foreseeable future, the fuel cost of the aircraft will further rise, and the use of turbofan engines will lead to excessive flight costs, it is not impossible for airlines to replace all the turbofan engines on their own aircraft with paddle fan engines. Comfort? That's got to be at the back of the line, too! No one will do a losing business. If you have any opinions, you can buy a private business jet yourself! If you don't have money, don't chirp.

Although it is impossible for airlines to say it so bluntly by then, the meaning should be very different.

Don't say that turboprop engines are inferior to turbofan engines, but you must know that the Tu-95 "Bear" strategic bomber that Lao Maozi began to develop in the early 50s still uses turboprop engines. Although it uses a turboscrew engine, thanks to its extremely excellent fuselage aerodynamic shape and wing airfoil design, the Tu-95 "Bear" strategic bomber is capable of cruising at a speed of 760 kilometers per hour and a maximum speed of 910 kilometers per hour.

Compared with the US strategic bombers of the same period, the US Air Force's B-"Stratofortress" strategic bomber, which uses eight turbofan engines, has a maximum speed of only 1 C 10 km/h and a cruising speed of 800 km/h. ,

On the other hand, the Tu-95 has a much higher modification potential than that of the B, and the three Tu-1 maritime anti-submarine/anti-ship planes that Zhang Lan is about to acquire from the Russian Far East Pacific Fleet are improved on the basis of the Tu-95, and there are countless other variants. As the old saying goes, the sophistication of weapons and equipment is important, but how they are used is also more important.

Zhang Lan pondered that since the turboprop engines adopted by Lao Maozi in the fifties could reach a level similar to that of turbofan engines, then an aircraft equipped with a more advanced prop engine than a turboprop engine could not be worse than a turboprop engine in any case!

Of course, the premise is that the design of the fuselage and wings must be done well, and the fact that Lao Maozi's Tu-95 was able to achieve this amazing speed is itself inseparable from its excellent fuselage and wing design.

In this way, the research of the propeller fan engine must be on! Not only the tiltrotor that you want to build in the future, but even various types of aircraft such as transport planes! Of course, the research of other aero engines naturally cannot be stopped, and the use of the propeller fan engine is still limited by the noise after all.

"Can you really handle it?" Zhang Lan was a little nostalgic for Brother Zhuzi's words: Uh, are you also good at airplanes? "It's not that I conceive you, no one can have your skills and attainments in piston internal combustion engines, but aero engines are still different from piston internal combustion engines after all."

I don't doubt it, but no matter how I hear it, there is a smell of nostalgia.

"How dare you underestimate us!?" Before Brother Zhu Zi could speak, Brother Ironskin's unhappy voice sounded, "Most of our deformations are cars, but it doesn't mean that we can only change into cars, we can also change into airplanes!" For all kinds of aero engines, our technology is at least ahead of your technology, well, this is really not good, your aviation technology is still in the most primitive thrust reverser stage, and the waste of energy is terrible! You still doubt our ability to use this kind of technology for I don't know how many years we have lost? ”

"Wait," Zhang Lan grasped the meaning of Brother Iron's words, "Brother Ironskin, do you mean that you can not only change into cars, but also into airplanes?" ”

"Nonsense!" Brother Zhu and Brother Ironhide said in unison, and their answers were unprecedentedly unanimous, "Otherwise, how can we go to war with Megatron and them?" If we can only run on the ground and can't fly in the sky, then aren't we the target of the mad Transformers flying in the sky? How is it possible to fight for so many years without a winner? Are you the damn Transformers you've watched too many cartoons and think we're Autobots, so we can only change cars? ”

Zhang Lan Khan: Isn't it! Don't you just think that Brother Zhu and Brother Tin can only turn into cars! Grandma is a bear, watching TV indiscriminately kills people! I'm also a pig, such a simple truth, don't you understand it if you think about it a little! I have long thought about the ability of Brother Zhu and Brother Tin to change planes, so how much time will I save in many things!?