Design Of Refrigeration System Of Environment Testing Chamber And Research Of Control Method

In this thesis, the current development trend of the manufacturing technology on environment testing chamber is studied. After analyzing and comparing with the refrigeration method in common use, we established the cooling mode of refrigeration system for the environment testing chamber. The combination of machinery and liquid nitrogen refrigeration was adopted in this mode, it can economize the cost of investment in construction, on the other hand, the constrained design parameters itself were attained. During this process, it can not only give us the calculation of the cooling load, but also the selection of the main components for the experiment chamber. Furthermore, it solved many other important issues, such as the ration between mechanical refrigeration and liquid nitrogen refrigeration, and how to calculate the consumption of the liquid nitrogen.Control system with stability and security played an important role in attaining the design parameters, we introduced in the advanced PID control technology instead of the relay-access control system in traditional, it works with the high-precision detection sensor technology together, making the whole system smart to operate, stable to use, and simple to guarantee, therefore, this environment testing chamber has great value in practical use.