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针对管内除垢与防垢及强化传热问题,对工程上应用较广的扭曲管、扭带管中旋流场内低浓度液固流场综合性能进行实验及模拟研究.结果表明,含粒子旋流场可提高流体湍流强度,与圆管相比,扭曲管和内插扭带圆管均有较好的旋流效果,相同Re下扭曲管的换热系数提高18.7%~30.1%,阻力系数提高13.1%~181.8%,综合性能评价因子平均提高15.5%,高于圆管和扭带管:而扭带管的换热系数比圆管提高5.6%~32.9%,阻力系数最高.对扭曲管内粒子传热性能进一步优化,模拟值与实验值的误差为10.7%~12%.旋流作用有利于提高液固流场的综合性能,但较高流速下该综合性能则逐渐降低.
In order to solve the problems of descaling and anti-fouling and heat transfer enhancement in pipe, the comprehensive performance of low-concentration liquid-solid flow field in the swirling flow field of twisted pipes and twisted pipes with wider applications is experimentally studied and simulated. The swirling flow field can increase the turbulence intensity of the fluid. Compared with the circular tube, both the twisted tube and the inserted twisted tube have better swirling effect. The heat transfer coefficient of the twisted tube increases by 18.7% -30.1% under the same Re, Coefficient increased by 13.1% ~ 181.8%, the overall performance evaluation factor increased by 15.5% on average, higher than the tube and twisted tube: while the heat transfer coefficient of the twisted tube increased by 5.6% ~ 32.9% than the tube, the coefficient of resistance was the highest. The heat transfer performance of the particles in the tube was further optimized, and the error between the simulated and experimental values was 10.7% ~ 12%. The swirling effect was beneficial to improve the overall performance of the liquid-solid flow field. However, the overall performance was gradually reduced at higher flow rates.