Aerodynamic Study on Supersonic Flows in High-Velocity Oxy-Fuel Thermal Spray Process

• 来源期刊: 热科学学报（英文版）
• 学科: 物理学
• 年，卷（期）: 2005,（2）
• 页码范围: 126-129
• 页数: 4页
• 分类号: O354.5
• 语种: 英文

摘要

To clarify the characteristics of gas flow in high velocity oxy-fuel (HVOF) thermal spray gun, aerodynamic research is performed using a special gun. The gun has rectangular cross-sectional area and sidewalls of optical glass to visualize the internal flow. The gun consists of a supersonic nozzle with the design Mach number of 2.0 followed by a straight passage called barrel. Compressed dry air up to 0.78 MPa is used as a process gas instead of combustion gas which is used in a commercial HVOF gun. The high-speed gas flows with shock waves in the gun and jets are visualized by schlieren technique. Complicated internal and external flow-fields containing various types of shock wave as well as expansion wave are visualized.