Research Of Refrigerating Equipment Used For High-accuracy Temperature Control System With Large Temperature Variation

The temperature controller test stand should satisfy the following requirements: the temperature of test chamber varies from 10℃to 50℃in the large range, and the temperature control precision is±0.05℃. The common small refrigerating equipment is difficult to reach such requirements. On the basis of previous test results, this research has deeply analyzed each component of the refrigerating equipment, which satisfies these requirements mentioned above, carried on optimum selection, and developed the small refrigerating equipment which fits the requirements of both large temperature variation and temperature control precision to settle the difficult problems during the test process.This research has studied the thermostatic expansion valve, the capillary tube and the manual regulated valve due to the theoretical analysis and the experiment. Among these three throttle apparatuses, the manual regulated valve is flexible and convenient to regulate, what's more, the flow of the refrigerant quantity can not be affected largely when the temperature of the control air varies in large range, which is in favor of the operation of the automatic control system. Hence, it is a good throttle method for the temperature control system with large temperature variation and high precision.The selection calculation of the evaporator used for the refrigerating equipment with large temperature variation and high temperature control precision must be accounted according to the dynamic method, that is to say, satisfying the requirements of both low temperature and high temperature. In fact, it is shown that the evaporation area in such condition is as large as 20%～30% than the common one.The practice results have proved that the selections of both the condenser and the compressor of the refrigerating equipment which fits the temperature control system with large temperature variation and high precision are similar to the common small refrigerating equipment.These research achievements can be used as references for the congener studies in the future.