Experimental on Metering Characteristics of Multi-hole Orifice

Multi-hole orifice（MO） as a new type of throttling element is designed,and the characteristics of the discharge coefficient,the head loss and anti-swirl performance are experimentally studied.Compared with that of the standard orifice,the discharge coefficient of MO is more stable,and less sensitive to the upstream swirl,and the head loss is close to that of the standard orifice.For the three pairs plate of equivalent β of 0.42,0.59,and 0.65,the variation of the MO’s discharge coefficient is lower than that of the standard orifice by 0.83%,2.02% and 1.67%,respectively.The MO performance is superior to the standard orifice in anti-swirl aspect for lower β（β=0.42）,while the situation becomes opposite for larger β（β=0.65）.