细水雾典型参数对舰船卧式排烟降温的数值模拟分析

Numerical Analysis on Influence of Typical Parameters of Fine Water Mist upon Cooling Effect of Ship’s Horizontal Smoke Exhaust

为了掌握细水雾对舰船排烟管道内烟气和管壁降温作用的机理和特性,提升舰船红外隐身能力,利用数值仿真技术对一舰船卧式排烟管道内细水雾系统的水雾颗粒粒径、流量、雾锥角,以及喷头出口流速对烟气和排烟管道壁面的降温影响进行比较,分析水雾系统各参数变化对排烟管道内烟气和管壁降温能力的改变程度,确定排烟管道出口的排烟温度与入口烟气速度、入口烟气温度、细水雾颗粒粒径、细水雾流量与烟气流量的比值以及细水雾速度相关,构建涵盖各主要影响参数的排烟管道出口烟气和管壁温降表征关系式,比较理论计算与数值模拟结果,验证关系式的正确性。

In order to deeply understand the cooling mechanism and characteristics of water mist on the smoke and wall in the ship’s smoke exhaust duct, so as to effectively improve the infrared stealth capability of the ship, the fine water mist flow field in a horizontal smoke exhaust pipe of a ship was numerically simulated. The effects of water mist particle size, flow rate, fog cone angle and nozzle outlet velocity on the smoke and wall cooling in the exhaust duct were compared. Based on the analysis of the degree of change of the cooling capacity of the smoke and the wall when the parameters of the fine water mist system change, the exhaust gas temperature at the outlet of the exhaust pipe was determined to be mainly related to the inlet gas velocity, the inlet gas temperature, the particle size of the fine water mist, the ratio of the water mist flow rate to the gas flow rate, and the spraying speed of the fine water mist. The expressions constructed could cover all of the typical influencing parameters of the fine water mist nozzle, and the correctness was verified by comparing the results.