What is the "Cradle of Aircraft" JF-22 Wind Tunnel? What does it look like? Understanding Experiments | Wind Tunnel | JF-22

In the development process of various types of aircraft, a large number of simulation flight experiments are required, but it is impossible to frequently test fly the aircraft in the sky. Therefore, wind tunnels have emerged, which is equivalent to artificially building a "flying sky" on the ground and is an essential large-scale aerodynamic experimental device for developing aircraft. Recently, at the Huairou Science City located in Beijing, the national treasure - JF-22 ultra high speed wind tunnel has just passed the acceptance inspection.

The JF-22, measuring 167 meters in length, can reproduce flight conditions up to 30 times the speed of sound

CCTV reporter Shuai Junquan: This is the National Key Laboratory of High Temperature Aerodynamics for Aerospace Flight. Beside me is the JF-22 Ultra High Speed Shock Wave Wind Tunnel, which has just passed the acceptance inspection. Its total length reaches 167 meters, and its various performance indicators can be said to be internationally leading. It also provides strong support for the development of our country's aerospace shuttle system and ultra-high speed aircraft.

As the cradle for the development of a new generation of aircraft, the JF-22 ultra high speed wind tunnel can reproduce flight conditions at altitudes of 40 to 90 kilometers, speeds up to 10 kilometers per second, equivalent to about 30 times the speed of sound.

Jiang Zonglin, researcher of the Institute of Mechanics of the Chinese Academy of Sciences and project leader of Huairou Shock Wind Tunnel: The first one is large. Our wind tunnel blows out a flow field with a diameter of 2.5 meters. Generally, the maximum diameter in foreign countries is 1.5 meters, so you can accommodate larger aircraft. The second time is long. At Mach 10, we reached 40 milliseconds, which is several times and several times higher than the advanced level of similar domestic and international standards. The accuracy of the experimental results is also high. The third one has high total temperature, high total pressure, and high performance. Now we can achieve temperatures ranging from 2500 degrees Celsius to 18000 degrees Celsius, and with total pressure, we can achieve temperatures ranging from 100 atmospheres to 10000 atmospheres. So there is no other wind tunnel in the world that can compare this performance.

CCTV reporter visits the interior of 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. After project acceptance, the research team first conducts research on the technology of back and forth flight between heaven and earth. What does the JF-22 ultra high speed wind tunnel look like inside? How to carry out experimental work inside?

CCTV reporter Shuai Junquan: Using the gap stage of the experiment, now we need to enter the interior of the JF-22 Ultra High Speed Wind Tunnel to take a look. This is its experimental chamber, which is relatively spacious. Its diameter reaches 4 meters, and the maximum size of the experimental model that can be tested can reach a length of 8 meters. The maximum speed of the airflow can reach 3 to 10 kilometers per second, allowing for a series of aerodynamic ultra high speed experiments.

Han Guilai, a researcher at the Institute of Mechanics of the Chinese Academy of Sciences and the site director of Huairou Shock Wind Tunnel: We are recently going to study such an aircraft with two-stage or multi-stage orbit entry. The rocket takes off and lands vertically. In the future, we will take off and land horizontally through the aircraft, then fly to an altitude of, say, 30 to 40 kilometers, release the second stage, and then fly upward to form such a relay mode, called two-stage or multi-stage orbit entry. So recently, we are also preparing an experiment of such a corresponding separation scheme, which is mainly to explore the process of the lower stage following the upper stage and generating a separation.

Jiang Zonglin: In terms of wind tunnel research, we have already solved the concept of high ultrasonic separation. From an experimental perspective, we have successfully and safely solved this problem. In addition, we also need to do a separation under different flight speeds, which can be done in any situation. After these situations are completed, obtaining this data will make aircraft design and flight experiments very easy.

How does a wind tunnel work? What are the characteristics of shock wave wind tunnels?

JF-22 Ultra High Speed Wind Tunnel, also known as Detonation Driven Ultra High Speed High Enthalpy Shock Wave Wind Tunnel. The name sounds particularly tall. As the cradle of aircraft, how does a wind tunnel work? What are the characteristics of shock wave wind tunnels? Let's listen to the expert's interpretation ↓

JF-12 and JF-22 cover all "flight corridors" experimental capabilities

The JF-12 replicated wind tunnel, successfully developed in 2012, has a total length of 265 meters, making it the largest and most advanced shock wave wind tunnel in the world at that time. The JF-22 ultra high speed wind tunnel, which has recently completed acceptance and started official operation. The JF-12 reproducing wind tunnel and the JF-22 ultra high speed wind tunnel are respectively the largest and most advanced shock wave wind tunnels in their respective fields, making China the only country in the hypersonic field with the ability to cover all "flight corridors" experiments. In the future, what major research and development projects will this important platform undertake?

The JF-12 reproducing wind tunnel and JF-22 ultra high speed wind tunnel can achieve experimental conditions of 1.5-3km/s and 3-10km/s respectively, jointly forming an aerodynamic experimental platform covering Mach numbers of 5-25 and flight heights of 25-90km.

Jiang Zonglin: Using a Mach number of 10, such as over 100 atmospheres and a 40 millisecond experimental time, we can conduct hypersonic engine tests. Our laboratory proposes a new type of engine called a stationary oblique detonation engine. Now we have achieved Mach 7 to Mach 9 using JF-12. It seems that our new engine has a higher thermal efficiency, 50% higher than traditional engines, and stable combustion. The JF-22 is preparing to go from Mach 9 to Mach 16. If such an engine is completed, I think it will be a great push for our country's next step in aerospace technology.

In addition, the scientific research team will also use this shock wave wind tunnel experimental platform to conduct research on gliding aircraft, space shuttle aircraft, multi-stage orbital vehicles, etc., to support and serve major needs and key technological breakthroughs in the field of hypersonic technology in the country.

Jiang Zonglin: At the level of Mach 20, we can make high-altitude gliders, which can be said to reach the world in an hour. If we achieve a Mach number of 30, in reality, we are using this Mach number for aircraft atmospheric re-entry, such as Mars exploration or orbiters returning to the atmosphere. So this wind tunnel covers the entire range from aerospace to aviation to detectors, so it has great application areas.