Abstract: In this paper the performance of uniform static pressure ventilating duct is analyzed on the basis of flow dynamics ,and its mathematic model offlow is deduced on the analyzing basis.At the same time the law and specialty of velocity’s variation and static pressure in the main ventilating duct are studied. In the end through the experiments the result of analysis is testified and the improving measures for the duct are pointed out.

Key words: air-conditioning； ventilating duct； static pressure； dynamics specific properties；