Abstract:

For circular vortex generator structure, the arrangement is studied using numerical simulation method for its influence on rectangular channel wall CaSO₄ crystallization fouling deposition process. At temperature of 300 K, velocity 0.5 m·s^-1 and CaSO₄ concentration about 3.0 g·L^-1, the influence of geometrical factors on the surface fouling deposition is analyzed, such as the length of circular vortex generators, arrangement, radius, and spacing. The results show that the fouling resistance decreases and then increases along the length of vortex generator and appears minimum at (4/8)H shocked strengths. It increases with the spacing of vortex generator, and for the spacing more than 55 mm the fouling resistance will gradually tend to that in smooth path. The fouling resistance increases with the radius of vortex generator. The same spacing and radius, length of (4/8)H, and arrangement on one side make the fouling resistance minimal.

Key words: vortex generator, column spacing, arrangement, length and radius, numerical simulation, CaSO₄ crystallization fouling, deposition, experimental validation

摘要：

为探讨圆形楞涡流发生器结构和布置方式对换热面污垢的影响,采用数值模拟方法研究了布置圆形楞涡流发生器矩形通道内壁面CaSO₄析晶污垢的沉积过程,同时计算并分析了入口流体温度为300 K、速度为0.5 m·s^-1、浓度为3.0 g·L^-1的CaSO₄过饱和溶液下圆形楞涡流发生器的楞长、布置方式、半径的大小以及纵向间距等几何因素对表面污垢沉积的影响。结果表明:污垢热阻值随涡流发生器楞长增加先减小后增大,而且在(4/8)H楞长处出现最小值;随涡流发生器列间距增大而增大,当间距超过55 mm后污垢热阻值逐渐趋于光通道的污垢热阻值;随涡流发生器半径增大而减小;相同列间距、半径以及当楞长为(4/8)H时,顺排靠边布置时其污垢热阻值最小。

关键词: 涡流发生器, 列间距, 布置方式, 楞长和半径, 数值模拟, CaSO₄析晶污垢, 沉积物, 实验验证