Design Optimization of an Oil-Flooded Refrigeration Single Screw Compressor

A single screw compressor is usually sealed by means of its tiny clearances. The theoretical research and the practice application shown that the leakage in the working process is always the key factor influencing the performance of this kind of compressor. Besides meeting the need of lubrication, the oil injection can greatly improve the sealing effect. It is obvious that the reduction of clearance, the increase of sealing line, low oil temperature and large oil rate can greatly reduce the leakage and improve the volumetric efficiency. But in the meantime, the flow resistance loss and the friction power are thus increased. This means an optimization problem. Taking the volumetric specific power (ratio of compressor power and cooling capacity) as the target, some structure parameters and oil-injection parameters of single screw compressor are optimized in this paper. And the results of optimization are also analyzed. It provides scientific basis for rational design and improving performance of the compressor.