Experimental analysis of the performance of a bidirectional single-unit air compressor with a semi-gear and rack mechanism in power transmission

In this paper, a bidirectional single unit air compressor equipped with two reciprocating pistons and operating with a new mechanism of semi gear and rack type in power transmission has been made, developed and analyzed. In this structure, there are two reciprocating pistons in two opposite positions to produce compressed air, therefore, there are two compressed air strock in each rotation of the output shaft. In the power transmission mechanism, a rack gear and a semi gear have been used, so that The rotation of the compressor shaft causes the rotation of the semi gear and finally, the reciprocating movement of the rack and the pistons. The results show that in the experimental situation, the amount of energy consumed to reach the tank pressure of 4 bar is equal to 142.6 kJ, while the minimum theoretical work of the compressor in the isotherm state to reach the same pressure is equal to 72.5 kJ and this represents 51% efficiency of this structure in the form of working in compressor mode. Also, the results show that using heat from waste sources to increase the tank pressure from 4 bar to 5 bar will lead to an increase in efficiency of about 60 percent.