通过对比条件一致的弓形折流板和螺旋折流板换热器的数值模拟结果,发现螺旋折流板换热器壳程绝大部分区域轴向速度占优,导致了螺旋折流板换热器壳程的压降和传热量均小于弓形折流板换热器.而螺旋折流板换热器三角区较高的切向流的原因是:三角区是上下游不同象限折流板区间接触“短路”的区域,故在这一区域存在较大压差会引起流体“短路”.同时,本研究也对比了螺旋折流板换热器数值模拟结果和工程半经验算法的计算结果,发现工程半经验算法得到的传热系数h偏低;且工程半经验算法中,对通过壳程半幅对称面的净质量流量考虑较简单,未考虑相邻三角区流体“短路”的影响,故有必要重新考虑螺旋折流板换热器热工设计校核中所用的传热系数h计算公式.%After the comparison of numerical simulation result of segmental baffle heat exchanger and helical baffle heat exchanger having identical condition,the present research find that the axial velocity component is dominant in majority of shell side,which cause the shell side pressure and heat duty of helical baffle heat exchanger is smaller than helical baffle heat exchanger.About the high tangential flow in triangle zone,it is the final reason that triangle zone is short circuit contact zone between up-stream and downstream baffle region in different quadrant,so there is large pressure difference in this zone,which finally cause the fluid flow short circuit.Meanwhile,the present research also compare the numerical simulation result and engineering semi-empirical algorithm result,it is found that the heat transfer coefficient h from engineering semi-empirical algorithm is lower,and the treatment of net mass flow rate through half symmetric plane in shell side is simpler in engineering semi-empirical algorithm,which doesn't consider the influence of adjacent triangle zone's short circuit.So it is necessary to consider the heat transfer coefficient h's equation in helical baffle heat exchanger thermal design and rating from beginning.
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