Development of system control for compressor valves

Gustavo Myrria Neto (Universidade Federal de Santa Caterina)

In the recent years with the growth of cities is observed a tendency of people living in smaller places. In these situations the noise generated by household appliances has acquired greater impact on comfort and even the health of an individual. The main goal of this work is to evaluate the potential of modification of suction's valve movement in order to reduce the noise level of a hermetic compressor used in domestic refrigeration systems. The pressure pulsation in the suction chamber, which is directly related to the movement of suction valve, excites the cavity which excites the shell and this radiates sound waves to external environment. Thus the strategy of this work is to modify the opening movement of the suction valve in order to change the pressure pulsation in the suction chamber and reduce the noise level associated to this transmission path. To achieve the aforementioned goals, a hermetic compressor is simulated using the program RECIP. Different movements are imposed on the opening of the suction valve. The next step is to develop a control system for this movement. At the end, the results of the simulation of compressor with the system control of the suction valve movement are obtained and evaluated. It is observed attenuations of the order of 10 dB in the pulsation in suction chamber and in the irradiated sound pressure level with the use of modified movement of suction valve.