All kinds of aircraft in the research and development process, need a large number of simulated flight experiments, but it is impossible to really let the aircraft frequently test fly, so the wind tunnel came into being, which is equivalent to artificially building a "flying sky" on the ground, is the development of aircraft indispensable large-scale pneumatic experimental device. Recently, in Huairou Science City in Beijing, the JF-22 ultra-high-speed wind tunnel has just passed the acceptance.
167 meters long The JF-22 can replicate flight conditions at about 30 times the speed of sound
CCTV reporter Shuai Junquan: This is the National Key Laboratory of High Temperature Aerodynamics of Aerospace Flight, next to me is the JF-22 ultra-high-speed shock wave wind tunnel that has just passed the acceptance, its total length reaches 167 meters, and its performance indicators can be said to be internationally leading, and it also provides strong support for the development of our country's aerospace shuttle system and ultra-high sonic speed aircraft.
As the cradle for the development of a new generation of aircraft, the JF-22 ultra-high-speed wind tunnel can replicate flight conditions at altitudes of 40 to 90 kilometers at speeds of up to 10 kilometers per second, equivalent to about 30 times the speed of sound.
Jiang Zonglin, researcher at the Institute of Mechanics, Chinese Academy of Sciences and leader of the Huairou Shock Wave Wind Tunnel Project: The first scale is large. Our wind tunnel blows out of this flow field has a diameter of 2.5 meters, generally the largest diameter abroad is 1.5 meters, so you can put a larger aircraft. The second time is long. At Mach 10, we reached 40 milliseconds, which is about several times and multiplied to the domestic and international advanced level, and the accuracy of the experimental results is also higher. The third has high total temperature, high total pressure and high performance. Now we can do 2,500 degrees Celsius to 18,000 degrees Celsius, and with total pressure, we can do 100 atmospheres all the way to 10,000 atmospheres. So this performance is not comparable to any other wind tunnel in the world.
The reporter of the main station visited the interior of the JF-22 ultra-high-speed wind tunnel
The research and development goal of JF-22 ultra-high-speed wind tunnel is mainly to solve the experimental research problems of ultra-high-speed flight technology, and after the project acceptance, the scientific research team first carried out the research of space-earth round-trip flight technology. What does the inside of the JF-22 ultra-high-speed wind tunnel look like? How to carry out experimental work inside?
CCTV reporter Shuai Junquan: Using the gap stage of the experiment, now we have to enter the interior of the JF-22 ultra-high-speed wind tunnel to take a look, this is its experimental cabin, which is still relatively spacious, its diameter reaches 4 meters, the maximum size of the experimental model that can be experimented can reach a length of 8 meters, and the maximum speed of the airflow can reach 3 to 10 kilometers per second, so that a series of aerodynamic ultra-high-speed experiments can be carried out.
Han Guilai, researcher at the Institute of Mechanics, Chinese Academy of Sciences, and site leader of the Huairou Shock Wave Wind Tunnel: We are recently studying such a vehicle with two or more stages into orbit, the rocket is vertical take-off and landing, in the future we will take off and land horizontally through the aircraft, and then fly to an altitude of 30 km to 40 km, and then release the second stage, and then fly up, forming such a relay mode, called two-stage or multi-stage orbit, so recently we are also preparing such a corresponding separation scheme experiment. The main thing is to explore the process of separation between the lower level and the upper level.
Jiang Zonglin: In wind tunnel research, we have solved the concept of high ultrasonic separation, and from an experimental point of view, we have solved this problem very successfully and safely. In addition, we have to do a separation under different flight speeds, which is that we can separate in any situation, and after these situations are done, if we get these data, it is very easy to design the aircraft and fly experiments.
How does a wind tunnel work? What are the characteristics of the shock wave wind tunnel?
JF-22 ultra-high-speed wind tunnel, also known as detonation drive ultra-high-speed high enthalpy shock wave wind tunnel. The name sounds particularly tall, as the cradle of the aircraft, how does the wind tunnel work? What are the characteristics of shock wave wind tunnels? Let's hear what the experts have to say↓
The JF-12 and JF-22 cover the full "flight corridor" experimental capability
In 2012, the JF-12 reproduction wind tunnel was successfully developed, with a total length of 265 meters, becoming the largest and most advanced shock wave wind tunnel in the world at that time. Recently, the JF-22 ultra-high-speed wind tunnel has completed acceptance and started official operation. The JF-12 reproduction wind tunnel and the JF-22 ultra-high-speed wind tunnel are the largest and most advanced shock wave wind tunnels in their respective fields, making Continental the only country in the hypersonic field with the ability to cover all "flight corridor" experiments. What major R&D projects will be carried out on this important platform in the future?
The JF-12 replica wind tunnel and JF-22 ultra-high-speed wind tunnel can achieve experimental conditions of 1.5-3km per second and 3-10km per second, respectively, and jointly constitute a pneumatic experimental platform covering Mach 5-25 and a flight altitude of 25-90km.
Jiang Zonglin: Using Mach number 10, for example, more than 100 atmospheres, and an experimental time of 40 milliseconds, we can do hypersonic engine tests. Our laboratory has proposed a new type of engine, called the standing oblique detonation engine. Now we have achieved Mach 7 to Mach 9 with the JF-12, and now it seems that our new engine is 50% more thermally efficient than conventional engines, and burns stably. The JF-22 is ready to go from Mach 9 all the way to Mach 16, and if there is such an engine after it is done, I think it will be a very big boost to the next step of aerospace technology for our country.
In addition, the scientific research team will also use this shock wave wind tunnel experimental platform to carry out research on gliding aircraft, space-earth round-trip vehicles, multi-stage orbit vehicles, etc., to support and serve the major needs and key technologies in the field of national hypersonic science and technology.
Jiang Zonglin: To the Mach number 20 level, we can do high-altitude gliding vehicles, which can be said to be an hour to reach the world. If we do Mach 30, we are actually aircraft atmospheric reentry, such as exploring Mars, orbiting vehicles and then entering the atmosphere after returning to use such a Mach number. So this wind tunnel covers the entire range from aerospace to aviation to detectors, so it has a large application field.
(CCTV reporter Shuai Junquan, Chu Erjia, Wang Shuai)