Abstract: By applying black box theory inlet pressure, inlet subcooling, outlet pressure and valve opening are selected as influence factors to flow coefficient of electronic expansion valve (EEV). The four parameters are performed experimental research and analysis through a special experimental rig of testing flow characters of EEV. Its reducing relative uncertainty of flow coefficient is between 1.97% and 6.28%. Based on the experimental and calculated database, a multiple regression is performed by which an experimental correlation is developed. According to the validity check, the correlation yields the relative deviations range from –7.0% to 6.6%.

Key words: Experimental correlation, Electronic expansion valve (EEV), Flow coefficient