摘要
采用FLUENT软件数值模拟氮和氦混合气体在拉伐尔喷管内对颗粒的加速过程,并与一维等熵定常流动理论值进行比较,同时研究混合气体中氦气含量对喷管出口处气体以及颗粒的速度和温度的影响。结果表明:喷管中气体参数的模拟值和一维理论值比较吻合,可以预计颗粒的出口参数,指导冷喷涂工艺。随着混合气体中氦气含量的升高,气体和颗粒的出口速度不断提高,温度不断降低,但速度和温度的变化率不断减小,在氮气中加入少量氦气可以提高气体和颗粒的出口速度,同时避免了全部使用氦气加速时的高成本。
The acceleration of the gaseous mixture of nitrogen and helium on particles in the de-Laval nozzle was analyzed using FLUENT software,and numerical results of gas flow were compared with one-dimensional steady isentropic theoretically ones.Moreover,the effects of the helium content of gaseous mixture on the gas and particles velocity and temperature in the nozzle exit were studied.The results show that the numerical values are similar to the theoretical ones,therefore numerical simulation can be expected to determine the process parameters to guide the cold spraying process.In additional,with the helium content in the gaseous mixture increasing,the gas and particles velocity increase,but temperature is lower,however,the rate of change of velocity and temperature decrease.When nitrogen with a small amount of helium gas is used as acceleration gas,particles velocity in the nozzle exit increases while the consumption of helium is reduced.
出处
《材料工程》
EI
CAS
CSCD
北大核心
2010年第8期12-15,共4页
Journal of Materials Engineering
基金
国家自然科学基金资助项目(50871019)
关键词
冷喷涂
混合气体
拉伐尔喷管
数值模拟
cold spraying
gaseous mixture
de-Laval nozzle
numerical simulation
