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综述冰浆输送过程和在换热器中的流动换热特性研究现状。目前对冰浆流动特性研究主要是为了解决输送冷流体过程中的压降、摩阻系数等问题,输送途径主要是直管、弯管,可控因变量包括含冰率、管道直径、冰浆粘度、流速、Re数等参数。此外,还对冰浆在水平直管中流动情况进行了数值模拟,提出了最值冰浆浓度和第一临界速度、第二临界速度等参数,并推测冰浆流动换热应从三段进行考虑。冰浆在换热器中的流动换热过程与管道输送相比,通道结构更复杂导致阻力损失变大、换热增强、相变程度大,同时还要考虑固体颗粒与流体之间的耦合作用,因此目前的研究主要停留在实验阶段,在实验基础上进行半经验公式的推导。基础性理论研究主要涉及两相流动、颗粒力学和相变潜热三方面。此外,对未来研究方向提出几点建议,尤其是应从微观颗粒受力和晶体结构角度探讨冰浆的流动换热情况,脱离原有单相流体研究方式,冰浆颗粒流动至少分三段研究。
The research status of ice slurry conveying process and heat transfer in the heat exchanger is summarized. At present, the study on the flow characteristics of ice slurry is mainly to solve the problems of pressure drop and friction coefficient during the delivery of cold fluid. The main transport routes are straight pipe and elbow pipe. The controllable dependent variables include ice content, pipe diameter, ice slurry Viscosity, flow rate, Re number and other parameters. In addition, numerical simulation of ice slurry flow in horizontal straight pipe was also carried out, and the parameters of ice slurry concentration, first critical velocity and second critical velocity were put forward, and the flow heat transfer of ice slurry should be considered from three sections . The flow and heat transfer process of ice slurry in the heat exchanger is more complicated than that of the pipeline transportation, resulting in larger resistance loss, stronger heat transfer and larger phase transition. At the same time, the coupling between the solid particles and the fluid should be considered Therefore, the current research mainly stays in the experimental stage and derives the semi-empirical formula based on the experiment. Basic theoretical research mainly involves three-phase flow, particle mechanics and latent heat of phase transformation. In addition, some suggestions for future research are put forward. In particular, the flow heat transfer of ice slurry should be discussed from the perspective of micro-particle force and crystal structure.