An Approach Towards Reed Valve Geometry Design

Pressure-actuated reed valves play an important role in the compression process of a refrigerator compressor. The material properties and geometrical parameters of the valve and geometrical properties of valve port determine the flow coefficient which in turn impacts the compressor efficiency. Also, the moving mass of the valve and its stiffness governs the transient response (valve flutter) which impacts life and reliability of the valve in operation. Therefore, it is imperative to carefully design the reed valves to maximize compressor performance while meeting the above requirements. The design of reed valves involves determining the geometrical parameters (length, width and thickness) and material properties (type of steel etc.). These properties are chosen such that they correspond to the desired mass and stiffness of the valve. This work mainly focuses on determining the basic valve topology (geometrical parameters) with the desired mass and stiffness of the reed valve as design constraints. In order to obtain the optimum reed valve mass and stiffness values, an in-house system level performance simulation model is used. An analytical finite element based model has been built that searches for geometrical parameters which meets both target valve parameters and material limitations for reliability and life. This provides multiple valve designs with different geometrical parameters and gives the designer the flexibility to choose the most suitable valve design for a targeted application. Additionally, the basic valve topology will facilitate a more detailed performance analyses, viz. flow-thermal simulations and flow-structure interaction.