冰浆流动换热特性的综述及模拟分析  

Review on the flow and thermal characteristics of ice slurry in resistance components

作　　者：刘圣春[1] 郝玲[1] 宁静红[1] 

机构地区：[1]天津商业大学机械工程学院,天津市制冷技术重点实验室,天津300134

出　　处：《低温与超导》2015年第11期59-65,77,共8页Cryogenics and Superconductivity

基　　金：天津市应用基础与前沿技术研究计划项目(15JCYBJC21600);天津市科研创新团队“食品冷链装置节能及储运新技术”(TD12-5048)资助

摘　　要：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。This paper reviewed the flow and heat transfer characteristics of ice slurry in resistance components, including transportation systems and heat exchangers. Pressure drop and friction coefficient of ice slurry were considered and mainly influ- enced by several variables, such as ice content, flow velocities, Reynolds number and diameters of tubes etc. when ice slurry flows through the transportation systems. Numerical simulation was conducted to analyze the flow characteristics of ice slurry in horizon- tal straight tubes using commercial software Ansys Fluent. Some index parameters were proposed, such as most value concentra- tion and critical velocities. Comparing with above condition, it was more difficult to analyze the flow and heat transfer behavior for the ice slurry in heat exchangers due to the more complex structure, bigger flow resistance and stronger phase change, on which condition only semi - empirical calculation models drawn by mass of experiments are available. In the present study, basic funda- mental theories were mainly involved in two - phase flow, dynamic theory of granular and phase transition theory. This paper pro- posed several suggestions on further study that deeply research of effects of interaction force between ice crystals and water mole- cule on micro level should be emphasized and flow condition might be divided into three sections with increasing velocities which completely differed from single -phase fluid.

关 键 词：冰浆 简单管道流动 数值模拟 换热器 

分 类 号：TQ051.13[化学工程]