Test and Analysis on Evolution Characteristics of Cavitation Flow in Regulating Valve for Coal Liquefaction
Particle image velocimetry(PIV)technology and vorticity analysis are used to measure the flow field in the regulating valve for coal liquefaction under different working conditions,and the influences of inlet pressure on the radial and axial velocity distribution in the regulating valve are also discussed.The results show that the jet formed by the effect of throttling orifice converges and form a whole towards the downstream.The axial velocity of the oil decreases firstly and then increases downstream,and tends to keep stable near the throat.The radial flow velocity of the oil is lower near the wall,while it is higher in the center area of the flow channel.There are vortices caused by the velocity gradient in the spool head and downstream,the strong positive vorti-ces and negative vortices show two oblique wide band distributions.One of the high vorticity area is close to the head of the spool attached to the wall,while the other high vorticity area is mainly concentrated in the middle of the flow channel towards downstream.Furthermore,with the increasing inlet pressure,each of the flow rate,the high-speed distribution area and the intensity of the vortex increases.
regulating valveparticle image velocimetry technologyvelocity fieldvorticity fieldurbulent ki-netic energy
NETL
NSTL
万方数据
维普
