Multi-Response optimization applied to a mechanically assisted reed valve of a hermetic reciprocating compressor

Abstract

• novel valve concept to improve variable speed compressors. • simultaneous improvement of efficiency, cooling capacity and reliability. • significant reduction of the valve impact velocities. Reed valves are widely used in hermetic reciprocating compressors for domestic refrigeration. They are crucial components in terms of efficiency, cooling performance and reliability of the compressor. While reed valves already cause a significant proportion of the thermodynamic losses in fixed speed compressors, they cause even more challenges in variable speed compressors. Especially in variable speed compressors, a further improvement of the reed valve dynamics requires the consideration of a new valve concept. In this work, a new and cost-effective concept of a mechanically assisted suction reed valve is introduced. Simulation based response modelling and a multi-response optimization approach are applied to systematically optimize the design. Simulations between 1500 rpm and 5000 rpm indicate the strengths and weaknesses of individual optimized design variants over a wide compressor speed range. Calorimeter and valve dynamics measurements show considerable improvements of the COP and the valve impact velocity.