| Summary: | 碩士 === 中原大學 === 土木工程研究所 === 94 === ABSTRACT
A numerical calculation procedure based on the least-squares finite element method (LSFEM) is employed to solve the Navier-Stokes equations and energy equation for simulating flow fields and heat transfer in a channel of a build-in circular tube with and without a rectangle splitter plate. For different Reynolds numbers (Re=200,600,1000) and different splitter plate lengths (0.2H,3H,4H) in this paper, the distribution for the streamline, pressure, temperature, and Nusselt number are discussed in detail.
When Reynolds number is greater than 40, the cylinder will present two rows of vortexes at rear of the cylinder, this is called Von Karman shedding cycle. When adding a splitter plate behind the circular tube, it can make vortexes move forward downstream or even cut down the vortexes. It will cut down the vortexes more with the growth of the splitter plate length. For the pressure distribution, the minimum values at both sides of circular tube decrease after installing the splitter plate so that the velocity of flow field increase accordingly. The presence of a splitter plate causes a general decrease in local Nusselt number behind the circular tube. The size of the section of the high heat transfer in the wake increases as the chord length of the splitter plate increases.
The numerical simulation by using the LSFEM is shown in good agreement with the experimental measurement.
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