船用蒸汽蓄能器充能管路流动冲击预测

Prediction on flow shock characteristics of marine steam accumulator charging pipe

[目的]为更好地开展船用蒸汽蓄能器充能管路结构设计工作,需进一步明晰船用蒸汽蓄能器充能管路动态充能机制。[方法]根据船用蒸汽蓄能器充能系统运行方式,首先建立充能系统数值模型,设定边界计算条件,然后利用数值计算与理论分析相结合的方法,研究充能过程中充能管路的热工、水力及振动特性,并建立蒸汽蓄能器充能系统流动冲击预报模型。[结果]结果显示,充能管路的弯管和三通管内蒸汽流速高、湍动能大、湍流耗散率高,造成充能弯管和三通管部位承受的流动冲击能量和应力较大,其中三通管部位的流动冲击能量和应力要高于弯管,可以预测充能三通管部位的破损可能最严重。[结论]探索出的大负荷扰动条件下的船舶蒸汽蓄能器充能管路流动冲击预报方法,可为实船蒸汽蓄能器充能管路设计提供数据参考。

According to the operation mode of marine steam accumulator charging system,the numerical model and boundary conditions for a fully charged system was established.By using numerical calculation with theoretical analysis,dynamic thermal,hydraulic and vibration characteristics of charging system pipeline were researched.The flow shock prediction model for steam accumulator charging system is established.The energy and stress distribution f pipeline flow shock in the charging pipe of steam accumulator.The prediction method of flow shock in the charging pipeline of ship's steam accumulator under the condition of large load disturbance is explored.The results show that,high steam velocity,high turbulent kinetic energy and high turbulent dissipation rate are found in the inner wall of elbow and T-shaped part of tee.Comparing with slow charging and quick charging of constant-speed opening valve,the maximum pressure drop,velocity and the turbulent kinetic energy is small under mode of quick charging of variable speed opening valve,which is conducive to ensuring the safe operation of marine steam accumulator.The results show that,high steam velocity,high turbulent kinetic energy and high turbulent dissipation rate in elbows and tee,which cause that flow shock and stress on the elbow and tee is large.The flow shock and stress in tee is higher than that in elbow pipe.It can be predicted that the damage of the tee may be the most serious.Therefore,these research results can provide data reference for the design of charging pipe for the actual marine steam accumulator.