Turbulence numerical simulation of flow characteristics of Laval nozzle top blow jet
(1. School of Metallurgy and Environment, Central South University, Changsha 410083, China;
2. Guangxi Nanguo Copper Co., Ltd., Nandan 547204, China;
3. Department of Metallurgical and Resource Engineering, Guilin University of Technology at Nanning, Nanning 530001, China;
4. Department of Materials Science and Engineering, Michigan Technological University, Houghton, MI 49931, USA;
5. State Key Laboratory of Comprehensive Utilization of Nickel and Cobalt Resources, Jinchuan Group Co., Ltd., Jinchang 737100, China)
2. Guangxi Nanguo Copper Co., Ltd., Nandan 547204, China;
3. Department of Metallurgical and Resource Engineering, Guilin University of Technology at Nanning, Nanning 530001, China;
4. Department of Materials Science and Engineering, Michigan Technological University, Houghton, MI 49931, USA;
5. State Key Laboratory of Comprehensive Utilization of Nickel and Cobalt Resources, Jinchuan Group Co., Ltd., Jinchang 737100, China)
Abstract: The turbulent characteristics of the top-blown Laval nozzle and the influence of pressure and Mach number were studied through numerical simulation. With 2.72% error between the results and the empirical formula, the results are reliable. Nozzle fluid is influenced by pipe structure, causing pressure and density to drop as speed increases. Differences in pressure and velocity between the jet and surrounding gas lead to jet velocity attenuation, flow expansion, deflection, and eddy currents. The optimal top blowing pressure is 0.6 MPa, and the center velocity and width of the jet are 345 m/s and 0.124 m, respectively, at 20De (De is the nozzle exit diameter). It achieves a maximum jet velocity of 456 m/s. The optimal nozzle Mach number is 1.75, with a maximum jet velocity of 451 m/s. At 20De, the jet center velocity is 338 m/s, with a width of 0.12 m.
Key words: top blow jet; numerical simulation; turbulence; flow characteristic; Laval nozzle