Refrigerant-22 flow through short tube restrictors was investigated. The analysis pertained to initially subcooled refrigerant flowing through short tubes with 5L/D20. The flow conditions studied were those typically found in heat pumps. Flow dependencies upon upstream subcooling, upstream pressure, downstream pressure, tube length, tube diameter, entrance chamfering, and exit chamfering were examined. A correlation and flow charts for mass flow rate prediction were developed from a large experimental data base.

KEYWORDS: experiment, R22, refrigerants, tubes, fluid flow, measuring, heat pumps, subcooling, pressure.