A Research On Wind Tunnel Technology During The Anti Japanese War

In the 1930 s and 1940 s,there were more than 10 wind tunnels in China.During the Anti-Japanese War,some of these wind tunnels were used to test aircraft models.This is a very important thing in the history of civil aviation technology,but it is rarely noticed by scholars studying the history of technology.The article compares the early aviation technology differences between China and the West.China is one of the earliest countries in the world to manufacture aircraft,but for a long time,there is no wind tunnel.The reason for it is that it is not needed,because China cannot independently develop aircraft.After 9·18 Incident and 1·28 Incident,the backwardness of Chinese aviation technology was recognized by the Chinese.Wind tunnels are considered necessary in order to improve aviation technology.The author investigated the literature about wind tunnels published at that time,learned about students returning to study aviation in China,and inspected the situation of Chinese people visiting foreign wind tunnels abroad.Before starting construction,China learned about wind tunnel technology.The construction of the wind tunnel was initiated by Tsinghua University and other departments,followed by the National Government,and achieved consistent results from bottom to top.The article analyzes the technical pedigree of the wind tunnel.It is mainly based on the German-American reflux wind tunnel,and the results are mainly achieved by this department.Three representative wind tunnels are emphatically studied.The Tsinghua 5-foot wind tunnel was completed and put into operation in 1936.It is a wind tunnel with high energy ratio and low turbulence.It has accumulated experience for large wind tunnels.The 15-foot wind tunnel in Nanchang was basically completed in 1937.It uses new technologies such as "thin shell" and "variable diameter".Its cost is very low and the technology is very advanced.They were all destroyed by the Japanese army.The design technology of the Nanchang wind tunnel was used to construct a 5-foot wind tunnel in Kunming.In terms of core technical indicators such as size,wind speed,and Reynolds number,the three wind tunnels are 8-12 years later than similar wind tunnels in the West.The article explores the role of wind tunnels in aircraft development.The article explores the role of wind tunnels in aircraft development.After examining the work content of the wind tunnel and the specific model of the aircraft,the author concluded that only a few models were designed with wind tunnel tests.The author discussed the obstacles encountered in wind tunnel development.Including the destruction of Japanese aggressors and the negative aspects of foreign aid,incomplete aviation technology chain,lack of engine technology,and backward material and fuel technology.There are also such things as insufficient government funding,weak integration of technical forces,and changeable aviation industry policies.During the Anti-Japanese War,foreign wind tunnel technology was smoothly transferred to China.While developing,it is accompanied by technological regression.The wind tunnel has changed from a study-research type to a research-production type,and there is a lack of independent and specialized production-type wind tunnels.Although it failed to fundamentally change the old way of importing a large number of foreign aircraft and imitating foreign aircraft,it made China’s aviation technology,especially aircraft manufacturing,enter the full-process learning stage,that is,from imitating foreign aircraft to imitating wind tunnels,and carrying out scientific research.At that time,specific wind tunnel tests and the introduction of aerodynamic theories promoted each other,accelerated the development of aviation science and technology,and was the beginning of China’s “de-dependence” in the field of aviation science and technology.During the war,wind tunnel construction and scientific research activities not only realized the transfer of wind tunnel technology,but also cultivated talents.The wind tunnel during the Anti-Japanese War is an important case in the history of modern Chinese aviation technology.Relevant research helps to deepen the history of aviation and can also provide some valuable content for enriching the history of the War of Resistance.