High-altitude flight faces extremely complex and harsh environmental conditions. Every factor for aerospace field, from extremely cold temperatures to thin atmospheric pressure, can have a significant impact on the safety and performance of an aircraft. As a key test equipment, temperature altitude chamber plays an indispensable role in simulating high-altitude environment, ensuring flight safety and optimizing performance.
(1) Temperature control mechanism
The temperature altitude chamber is equipped with an advanced cooling and heating system, which can precisely adjust the temperature inside the chamber. Its refrigeration system adopts cascade refrigeration technology, the low temperature level can reach -40 ° C or lower, the high temperature level can reach 150℃, the required temperature value can be set and maintained in a large range. Its temperature sensor monitors the temperature change in the chamber in real time, and feeds back to the control system to ensure that the temperature fluctuation is controlled within a very small range, and can generally be accurate to ±0.5 ° C, to provide a highly stable temperature environment for the test of aircraft components.
(2) Altitude simulation principle
In order to simulate different altitudes, the altitude chamber uses equipment such as vacuum pumps to change the air pressure inside the chamber. According to the ideal gas equation of state, there is a specific correspondence between air pressure and altitude. In general, for every 1,000 meters of rise, the air pressure drops by about 12% to 13%. The altitude range from 0 meters to 40,000 meters can be simulated, and the minimum air pressure can be reduced to less than 0.5kpa. In this process, the well-sealed altitude chamber ensures stable air pressure, and the pressure sensor is equipped to accurately measure the pressure value.
(1) Aircraft component testing
The various components of the aircraft are subjected to rigorous testing in temperature altitude chambers. As the heart of aircraft, the performance of aero-engine at different altitudes and temperatures is directly related to flight safety and efficiency. In the test chamber, the engine can be simulated during takeoff (0-1000 meters above sea level, 15-30 ° C), cruise (9000-12000 meters above sea level, -50-60 ° C), landing (0-2000 meters above sea level, 0-30 ° C). Temperature and other environmental conditions faced by different flight stages to test its thrust output, fuel combustion efficiency, heat resistance and cold resistance of components. For example, in the high altitude and low temperature environment, the fuel atomization effect of the engine may be affected, and the fuel injection system can be optimized through the test chamber test to ensure the stable operation of the engine under various conditions.
Avionics also need to be tested in the altitude chamber. Electronic components in low temperature and low pressure environment may have performance drift, signal transmission failure and other problems. By carrying out a long period of high and low temperature cycle (-55 ℃ to +70℃ cycle) in the test chamber and the pressure test at different altitudes (such as the pressure corresponding to the altitude of 0 m to 30,000 m), reliable electronic components can be selected, and the design of heat dissipation and anti-interference of the equipment can be optimized. Ensure the accuracy and reliability of avionics system in high altitude flight.
(2) The whole machine environment adaptability verification
During the development of the aircraft, the entire aircraft also needs to enter the temperature altitude test chamber for simulated high-altitude flight tests. In the test chamber, it is possible to simulate the temperature and altitude changes that the aircraft faces when flying on different routes and in different seasons. From the cold polar route (the lowest temperature can reach below -60 ℃, the altitude is 0-10000 meters) to the hot tropical flight (the temperature is 30-40 ℃, the altitude is 0-15000 meters), from the low-altitude flight to the high-altitude area such as crossing the Tibetan Plateau (the altitude is 4000-10000 meters), Temperature (-30-40 ℃), the structural strength of the aircraft, air tightness, flight control system, fuel system, etc., are fully tested in the test chamber.
Through this whole machine test, the problems existing in the design and manufacturing process of the aircraft can be found in advance, and the overall performance of the aircraft can be optimized and adjusted to ensure that the aircraft can operate safely and stably in actual flight.
The technological development trend of temperature and altitude test chamber in precision control, expansion of simulation range and improvement of intelligent automation degree in the future is discussed, and the role of these innovations in promoting the progress of aerospace industry is discussed.
With the continuous development of aerospace technology, the requirements for temperature and altitude test chamber are becoming higher and higher, and its technology is constantly innovating and improving. In the future, the test chamber will be more accurate in the precision control of temperature and altitude simulation. Advanced sensor technology and intelligent control systems will enable smaller temperature fluctuation ranges, such as ±0.1 ° C, and more accurate altitude simulation, providing data support closer to the real environment for aircraft testing.
In terms of the expansion of the simulation range, the test chamber will not only be limited to the existing flight environment simulation, but also will be able to simulate more extreme space edge environment, hypersonic flight environment, etc. This will help promote the development of new types of aircraft, such as space aircraft, hypersonic vehicles and so on.
The improvement of intelligence and automation is also an important development trend of temperature and altitude test chamber. The test chamber will have automatic diagnosis, automatic adjustment of test parameters, remote monitoring and other functions. Operators can operate and monitor the test chamber through a remote terminal, greatly improving test efficiency and safety. At the same time, the test chamber will be able to integrate with computer aided design (CAD), computer aided engineering (CAE) and other software to achieve seamless docking of test data and design analysis, and accelerate the development cycle of the aircraft.
