Outer Space Simulation Test Chamber

Main Technology Parameters

(1) Ultimate vacuum: better than 1×10^﹣8Pa

(2) Working vacuum:better than 1.3×10^﹣8Pa

(3) Temperature range: ﹣190℃~+200℃(4) Temperature Accuracy：±0.5℃

(5) Temperature of the heat sink: ≤100K(6) Uniformity of heat sink temperature: ≤±5℃

(7) Black paint for inner wall of heat sink, Absorption of sunlight by heat sink≥0.95 Hemispheric emittance≥0.90, The outer surface is equipped with radiation shield.(8) Infrared heating heat flux density 100W/m2~1800W/m2

(9) With vacuum degree and temperature measurement function

Solar irradiation environment and simulation

The sun radiates enormous energy into space all the time. The wavelengths of sunlight cover a wide area from10-14 M（γgamma rays） to 14 meters (gamma rays) to 104 meters (radio waves), Different wavelengths of sunlight radiates different amounts of energy. Visible light radiates the most energy. With visible and infrared radiation accounting for more than 90 percent of the sun's total radiation energy. 

In the orbit flight, the spacecraft and the Eva spacesuit mainly receive three parts of radiation energy: Energy from the sun's visible and infrared radiation, the earth reflects energy from the sun and heat from the earth's atmosphere. The energy absorbed by spacecraft and Eva spacesuit affects its temperature and distribution. The energy absorbed depends on the surface material characteristics of its structure and shape and flight trajectory. At wavelengths less than 300 nanometers, the radiation energy is a tiny fraction of the sun's total, However, the optical properties of the material surface will be greatly changed. The ultraviolet radiation effects are mainly reflected by photochemical effects and photoquantum effects. 

The solar radiation simulation test can simulate the solar spectrum thermal effect and solar spectrum photochemical effect produced by solar radiation environment on spacecraft and Eva spacesuit. If only the thermal effect is simulated, it is called outer space heat flow simulation. There are two ways to simulate heat flow outside space, one is the in-jet simulation method, also known as solar simulation method; The other is absorption heat flow simulation, also known as infrared simulation. The solar simulation method should be used for the specimen with complex shape and surface material; If the shape is regular and the surface material is single, infrared simulation method can be used. If the photochemical effect of ultraviolet irradiation environment needs to be simulated, the ultraviolet irradiation simulator can be used.

Space cold black environment and simulation 

The equivalent temperature of the space is about 3K and the thermal absorption rate is 1, It can be thought of as an ideal black body without thermal radiation or reflection . When there is no solar irradiation, space is a completely cold and dark space . In this cold and dark environment, all the heat energy emitted by the object is completely absorbed .Therefore, it is also called heat sink environment. The cold black environment has great influence on the thermal performance of spacecraft and Eva spacesuit, To develop spacecraft and Eva spacesuit, it is necessary to conduct thermal vacuum and thermal balance tests in the simulated cold and black environment. Verify whether its thermal design and thermal performance meet the requirements.

In order to simulate the space cold and dark environment, Components usually made of aluminum, copper or stainless steel. The inner surface is coated with special black paint with high absorbency and liquid nitrogen is injected into the structure. This device is called heat sink. At present, all the spaceflight countries use this kind of heat sink with liquid nitrogen as the cold source to simulate the space cold and black environment. Because the thermal analysis theory calculation and the test data analysis indicated, heat sink with 77K liquid nitrogen temperature and absorption rate above 0.9 was used to simulate the space cold and black environment, and the simulation error was only about 1%. It can fully meet the requirements of simulation test of cold and black environment. In addition, the pursuit of lower temperatures is unnecessary and will greatly increase the technical difficulties and investment in analog equipment.

Vacuum container

The vacuum container is a horizontal cylinder with an open door at one end，One end is a butterfly head. The vacuum container and head are made of 0Cr18Ni9(304) stainless steel. The base is made of carbon steel. The welding adopts inner ring argon arc welding. Simulation of high and low temperature vacuum environment in the main tank 0 key process control of tank production.Door flange integral heat treatment, eliminate stressWeld color inspection, re - helium mass spectrometry leak detection, The overall leakage rate is≤1×10^﹣6Pa.L/S.