关键词: 流场模拟, 乙苯过热器, FLUENT模拟, 支持板

Abstract: Models of shell and tube ethylbenzene-steam super-heater were established based on the theory of similarity in geometry and the number of Res. The FLUENT 17.2 was used to simulate the flow field of super-heater. The impact of mass flow in shell-side on heat transfer coefficient, pressure drop, value of Nu?Pr-1/3were investigated. At the same time, the influences of accessories of shell-side on the flow field and heat transfer were studied. The results showed that the distribution of flow field is uneven in shell-side and there exists flow dead zones on the lee surface of the baffles. As the flow rate increases, the heat transfer coefficient and pressure drop enlarge. Fitting Nu?Pr-1/3and Res in logarithmic coordinates, the curves had a good linear relationship. The simulation results had a good agreement in heat transfer coefficient and pressure drop with the Bell-Delaware method; under the identical pressure drop, the heat transfer and flow dead zones decrease with the increase of baffles in number, while the pressure drop in shell-side and heat transfer coefficient increased; the bypass baffles could effectively reduce the bypass flow to improve heat transfer. And the anti-flush tube could improve the flow field uniformity at the inlet of the shell. The support plates caused uneven distribution of flow in shell-side and lowered the heat transfer coefficient and pressure drop of shell-side decreased, which adversely affect the overall heat transfer coefficient of the super-heater. By the simulation of flow field and heat transfer performance, it is found that the setting of the support plates is an important reason for the deterioration of the heat transfer performance of the industrial ethylbenzene super-heater.

Key words: flow field simulation, ethylbenzene super-heater, FLUENT simulation, support plates