摘要
粒子的速度和温度对多功能超音速火焰喷涂层的性能有决定性作用,它取决于经拉伐尔喷嘴加速后的焰流速度和温度.文中计算了拉伐尔喷嘴入口、喉部与出口三个特征截面的燃气速度和温度,并对喷嘴特征尺寸和型面进行了优化设计.保证在氧气和空气助燃状态下都能达到超音速,实现了焰流速度与温度在大范围内的连续可调.并在喷嘴的出口形成负压以实现送粉的通畅,焰流速度调节范围约为1 400～2150m/s,温度调节范围约为1 400～2600℃,可满足金属、合金和陶瓷材料的喷涂要求.
Particle temperature and velocity is critical to the performance of coating sprayed by High Velocity Oxygen/Air Fuel spray system, which is mostly dependent on the flame temperature and velocity accelerated by convergent-divergent nozzle. Gas characteristics of inlet, throat and outlet of the nozzle are calculated. Characteristic diameter and inner shape of the nozzle is designed according to aerodynamics. The results show that the velocity of the flame reaches supersonic while oxygen and air is used as combustion-supporting gas respectively. At the same time, the pressure of the nozzle outlet is less than the ambient pressure, which is advantageous to powder feeding. Flame velocity can be continuously adjusted from 1400 to 2150 m/s, while flame temperature is 1400-2600°C. The adjustable flame can meet the requirement of spraying coating for metal, alloy and ceramics.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2005年第8期61-64,共4页
Transactions of The China Welding Institution
关键词
拉伐尔喷嘴
粒子速度
粒子温度
涂层
Aerodynamics
Coatings
Nozzles
Structural optimization
