베르누이 부상유동의 이론해석 및 수치해석 연구

Abstract

Key Words: Bernoulli Principle(베르누이원리), Gas Levitation(기체부상), Compressible Flow(압축성유동),Non-Contact Transportation(비접촉이송), Flow Choking(유동초킹)초록: 공압부상은베르누이원리에기초한다. 그러나공압부상방법은제품의원가상승의요인이되는대량의유량을소모하는것으로알려져있다. 이논문에서는베르누이부상유동의통찰력을얻기위해수치해석연구를수행하였다. 3차원압축성Navier-Stokes 방정식과SST k-ω 난류모델에유한체적법을적용하여계산하였다. 기체유량, 공정제품의직경그리고원형실린더와공정제품사이의간극을다양하게변화하여공정제품주위의유동특성을조사하였다. 그결과부상력을위한최적의간극과공급기체유량이증가하면큰부상력이발생한다는것을알았다.Abstract: Pneumatic levitation is based upon Bernoulli’s principle. However, this method is known to requirea large gas flow rate that can lead to an increase in the cost of products. In this case, the gas flow rateshould be increased, and the compressible effects of the gas may be of practical importance. In the presentstudy, a computational fluid dynamics method has been used to obtain insights into Bernoulli levitation flows.Three-dimensional compressible Navier-Stokes equations in combination with the SST k-ω turbulence modelwere solved using a fully implicit finite volume scheme. The gas flow rate, workpiece diameter,and clearancegap between the workpiece and the circular cylinder were varied to investigate the flow characteristics inside.It is known that there is an optimal clearance gap for the lifting force and that increasing the supply gasflow rate results in a larger lifting force.