在氨气吸收过程中增加了宏观磁场力,考虑了吸收过程中降膜溶液膜厚的变化、膜厚方向的对流以及氨水溶液物性的变化,建立了磁场条件下垂直管外氨水降膜吸收数学模型。在磁感应强度0-3T范围内,对数学模型进行数值求解,得到温度、浓度、速度分布等参数。结果显示磁场对于氨水降膜吸收过程有一定的增强作用。
Magnetic field was applied in the absorption process of ammonia-water absorption refrigeration. The numerical model of falling film absorption outside vertical tube with ammonia-water in the presence of magnetic field was established. The macroscopic magnetic force was added in the equation of momentum. In the process of modeling, the variation of falling film thickness, variation of physical characteristics of ammonia-water and convection in the direction of film thickness were considered. The distributions of temperature, concentration and velocity of falling film were obtained within 0-3 T of magnetic induction intensity by numerical simulation. The results showed that the absorption heat, absorption mass, mass transfer coefficient increased with the increase of magnetic induction intensity. The falling film absorption with ammonia-water could be intensified to some degree by external magnetic field.