Abstract:The standard orifice plate flowmeter faces limitations in accuracy and applicability in industrial applications, and to improve its performance, multi-hole orifice flowmeter is increasingly used. In order to study the influence of structural parameters of multi-hole orifice plate on the performance of orifice plate flowmeter, the multi-hole orifice plate with inner diameter of 40 mm, multi-hole orifice diameter ratio of 0. 4 and thickness of 3 mm is used as the research object, and the multi-hole orifice plate model with different number of holes and clearance rate is designed. Numerical methods are used to analyze the flow characteristics of the multi-hole orifice flowmeter. The results show that the pressure loss coefficient of the multi-hole orifice flowmeter decreases with the increase of the number of holes, while the discharge coefficient increases with the increase of the number of holes. The clearance rate has little effect on the pressure loss coefficient and discharge coefficient of multi-hole orifice flowmeter, but increasing the clearance rate in a certain range can effectively reduce the pressure recovery length.