Enhancement of Exit Flow Uniformity by Modifying the Shape of a Gas Torch to Obtain a Uniform Temperature Distribution on a Steel Plate during Preheating

The objective of this study is to improve the exit flow uniformity of a gas torch with multiple exit holes for effective heating of a steel plate. The torch was simulated, and combustion experiments were performed for validation. Based on a basic model, three different revised models were designed and analyzed with the software ANSYS FLUENT 18.2. The flow uniformity (γ) of the velocity distribution at the multiple exit holes was investigated with the pressure drop ranging from 100 to 500 Pa. The basic model had flow uniformity ranging from 0.849 to 0.852, but the three new models had γ1 = 0.901–0.912, γ2 = 0.902–0.911, and γ3 = 0.901–0.914, respectively. The maximum percentage difference of the flow uniformity index between the three new models and the basic model was 7.3%. The basic model with nonuniform flow distribution made a temperature difference of the back side of the steel plate from the center to the edge of around 229 °C, while the modified model with uniform flow distribution had a smaller temperature difference of 90 °C. The simulation results showed good agreement with our experimental results for both the basic model and the modified model. The modified gas torch made a wider and more uniform temperature distribution on a preheated steel plate than the basic one. The results revealed that a trade-off between cost and flow uniformity, as well as the new gas torch, could be applied to a steel-plate preheating process before welding.

[1]  Li Zhijun,et al.  Experiment and Simulation Investigation on the Characteristics of Diesel Spray Impingement Based on Droplet Impact Phenomenon , 2018 .

[2]  Derek Dunn-Rankin,et al.  Electric Field Induced Changes of a Diffusion Flame and Heat Transfer near an Impinging Surface , 2018 .

[3]  M. Heggemann,et al.  CFD Simulation and Experimental Validation of Fluid Flow in Liquid Distributors , 2007 .

[4]  Sudarshan Kumar,et al.  Experimental and Computational Determination of Laminar Burning Velocity of Liquefied Petroleum Gas-Air Mixtures at Elevated Temperatures , 2013 .

[5]  Sylvain Lalot,et al.  Flow maldistribution in heat exchangers , 1999 .

[6]  S. Sahu,et al.  Analysis Of Heat Transfer Characteristics Of Flame Impinging To A Plane Surface Perpendicular To Flame Jet Axis , 2013 .

[7]  Anil K. Purimetla,et al.  CFD studies on burner secondary airflow , 2009 .

[8]  Tian-Hu Zhang,et al.  Optimization of gas mixing system of premixed burner based on CFD analysis , 2014 .

[9]  S. V. Prabhu,et al.  Effect of preheated mixture on heat transfer characteristics of impinging methane–air premixed flame jet , 2015 .

[10]  M. Saber,et al.  Methodology for multi-scale design of isothermal laminar flow networks , 2011 .

[11]  Lingai Luo,et al.  Experimental investigation of the flow distribution of a 2-dimensional constructal distributor , 2008 .

[12]  Jon T. Van Lew,et al.  Experimental study of the flow distribution uniformity in flow distributors having novel flow channel bifurcation structures , 2012 .

[13]  Jon T. Van Lew,et al.  CFD STUDY ON FLOW DISTRIBUTION UNIFORMITY IN FUEL DISTRIBUTORS HAVING MULTIPLE STRUCTURAL BIFURCATIONS OF FLOW CHANNELS , 2010 .

[14]  Wenjie Lv,et al.  Uniform distribution design and performance evaluation for UU-type parallel mini-hydrocyclones , 2014 .

[15]  Min Wei,et al.  Heuristic shape optimization of baffled fluid distributor for uniform flow distribution , 2015 .

[16]  de Lph Philip Goey,et al.  Analysis of the heat transfer of an impinging laminar flame jet , 2007 .

[17]  Peiwen Li,et al.  Even distribution/dividing of single-phase fluids by symmetric bifurcation of flow channels , 2013 .

[18]  J. Corriou,et al.  Optimal design for flow uniformity in microchannel reactors , 2002 .

[19]  Giancarlo Sorrentino,et al.  Study of aerodynamic performances of different wind tunnel configurations and air inlet velocities, using computational fluid dynamics (CFD) , 2016, Comput. Electron. Agric..

[20]  Lingai Luo,et al.  Multiscale optimization of flow distribution by constructal approach , 2005 .

[21]  Lingai Luo,et al.  Experimental study of constructal distributor for flow equidistribution in a mini crossflow heat exchanger (MCHE) , 2008 .

[22]  Iradj Sattari-Far,et al.  Study on welding temperature distribution in thin welded plates through experimental measurements and finite element simulation , 2011 .

[23]  Peiwen Li,et al.  The flow downstream of a bifurcation of a flow channel for uniform flow distribution via cascade flow channel bifurcations , 2015 .