Aerodynamic of a Double Concentric Jet with Bluff-Body

• Main Authors: Chu,Chin-Hwang, 邱青煌
• Other Authors: Ma,Hsaio-Kang
• Format: Others
• Language: zh-TW
• Published: 1993
• Online Access: http://ndltd.ncl.edu.tw/handle/42024035934489513290

碩士 === 國立臺灣大學 === 機械工程研究所 === 81 === The concentric bluff-body jet burner is widely used in industrial combustion engines. This kind of burner often generates a considerably complex recirculation zone behind the bluff body. As a result,the fuel often remains in the recirculation zone , achieving the effect of flame persistence. investigates the variations of the fluid dynamics as the fluid is injected into This study a closed projecting combustion chamber through a double concentric bluff-body jet swirless burner. The observation and measure of the fluid dynamics in our experiment are conducted under an isothermal circulation. The controlled parameters in our experiment are variations in the blockage ratio of the center bluff-body, the cone angle of the bluff-body, and the velocity ratio (Us/Up) of the secondary jet and primary jet; the injection of helium bubbles into the primary and secondary jets to observe the recirculation zone behind the bluff-body,the usage of Tufts for observing the characteristics of corner recirculation zone, and the measure of the average velocity of each point within the fluid dynamics by the five-hole pitot tube. The pressure taps were used for wall static pressure measurment.