An experimental comparison between performances of modular silicon expansion valve and thermal expansion valve in mobile ac system.

Modular silicon expansion valve (MSEV) is an electronically controlled expansion valve which has the ability to control the degree of superheat at the outlet of evaporator. This paper studied the effect of evaporator outlet superheat on system performance and compared with a thermal expansion valve (TXV) system. The experiments were carried out in working conditions with environment temperature ranging from 27°C to 45°C and, compressor rotational speed ranging from 800-2500 RPM. It is found that under most working conditions the performance of MSEV system is better than that of TXV system, the maximum improvement of cooling capacity compared to TXV system is 19% while the COP is almost the same. Through the optimization of superheat at evaporator outlet, a much better system performance can be achieved.