전산유체역학 방법을 이용한 석탄 입자 수송관에 대한 고체-기체 이상류의 유동 형태 및 압력 손실 특성 고찰 = Investigation on the Flow behavior and Pressure Loss Characteristics of Solid-gas Two-phase Flow in Coal-transport Pipeline by Using CFD Method

다국어 초록 (Multilingual Abstract)

CFD modeling and numerical calculations are performed for vertical, horizontal pipes and elbows, which are the main flow elements used in the pneumatic coal-transport system of pulverized coal combustion furnaces and fluidized bed gasification facilities. The coal-gas flow inside the flow element is modeled by combining the Reynolds stress averaged Navier-Stokes equation solver (RANS), k- ε turbulence model, and discrete phase model (DPM). Using the developed coal-gas flow analysis model, numerical calculations are performed to investigate the gas flow path, coal particle behavior, and pressure loss characteristics of the flow elements at different coal/gas loading conditions. The results of this prediction show that the coal-gas flow behavior of each flow element changes from dilute flow to dense flow pattern at a specific coal/gas load ratio where the pressure loss suddenly increases. From these numerical results, the present study also provides limited coal/gas load conditions to secure a stable coal supply and correlations for the pressure loss of horizontal, vertical, and elbow pipes that can be used in the design of actual coal transport pipes. The prediction accuracy of this method is verified by comparing the measurement results of coal transport pipes attached to the actual fluidized bed test facility with the prediction results by the present correlations.