关键词: 新型节流件, 汽蚀, 数值模拟

Abstract:

There is no reason in the design of orifice plate for condensation regulating pipeline,which could lead to cavitation downstream the orifice plate and brush pipeline with high fluid velocity.Severe vibration and brush corrosion were induced.Consequently,these affected the safety and stability of condensation pipeline extremely.Based on the mechanism of porous muffler with noise reduction,a new inclined hole hedge throttle orifice with the function of preventing cavitation and slow brush was proposed.The Bernoulli equation and block pressure difference method were introduced.Its aperture,and the thickness of the series were calculated and then two-stage inclined hole throttle orifice was obtained.The designed single-stage and two-stage throttle orifice were analyzed by means of numerical simulation.The calculated results show that the large scale vortex and the cavitation phenomenon would occur downstream single-stage throttle orifice,which caused the vibration for condensation pipeline easily.Two-stage throttle orifice not only could avoid cavitation from throttle orifice but also bring about fluid hedge jet effect.This may counteract jet energy from different inclined holes each other and slow fluid brush.The results of numerical simulation were basically consistent with theoretical design data. Therefore,the calculation method could provide theoretical support for the structural design of throttle orifice applying to marine condensation pipeline.

Key words: new throttle orifice, cavitation, numerical simulation