Numerical Solution of Non-uniform Grids of Laminar Flow in a Parallel Plate

• Main Authors: Yao-Chang Hsieh, 謝耀昌
• Other Authors: Hsien-Yu Lei
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/95441574498121194283

碩士 === 國立臺灣海洋大學 === 機械與輪機工程學系 === 93 === ABSTRACT The naro technology has been employed various applications in recent years. In the field of Computational Fluid Dynamics (CFD), fluid flow simulation replaces a lots of experiments in analyzing flow & heat transfer interactions. This results are mainly because of the mush faster CPU & mush higher capacity of the RAM due to the development of naro technology. The objective of this study is to use Non-Uniform Grid set-up with Patankar’s SIMPLER Algorithm to analyze the entrance region of the internal flow between a parallel plate. Sudden contraction flows are also studied. It is expected that much fewer grid points can be used in the non-uniform grid set-up than regular uniform gird so that complicated flows can be simulated more correctly with non-uniform grid. The fully developed flow & the developing flow in the entrance region with uniform inlet flow were analyzed. Results are compared with those of analytical or empirical correlation to verify the accuracy of the developed CFD code written in FORTRAN. It is formed that the non-uniform grid set-up has much better accuracy than the conventional uniform gird set-up so that more complicated flow field can be analyzed. The non-uniform gird was also used to analyze the internal flow with obstructions and shows the same advantages over uniform grid. It is concluded that grids, CPU time, and accuracy in flow simulations can be improved developed dramatically using non-uniform grid. The finer grids set-up are always recommeded in the flow region with higher shear stress (velocity gradient normal to the shear) or pressure gradient, such as in the entrance region of a flow inlet or flow with recirculation. The program can be expanded to include an energy solver so that thermal effects of flow convection can be studied. It can be easily adapted to solve flow fields with obstructions or 3-D flow. It is recommended non-uniform gird set-up in cylindrical coordinate or in turbulence region (higher Reynolds No.) can be investigated in the future and more practical engineering applications can be reached.