从场协同到热力学耦合:流动换热强化的热力学机制  

From Field Synergy to Thermodynamics Coupling:Thermodynamics Mechanism for Convective Heat Transfer Enhancement

作　　者：卢小平[1] 俞树荣[1] 郭丹丹[1] 

机构地区：[1]兰州理工大学石油化工学院,兰州730050

出　　处：《机械工程学报》2015年第10期160-163,171,共5页Journal of Mechanical Engineering

基　　金：国家自然科学基金(51275225);甘肃省自然科学基金(111ZRJZA034);国家质检公益专项(201310152)资助项目

摘　　要：根据热流的散度方程,分析质量流与热流之间不同相位关系时流动换热强化的两种热力学机制。当质量流与热流之间同相位时,两者的相位差越小,流动换热的强度越大,它反映两个正熵产率的自发过程之间能量传递的场协同机制,且传热过程熵产率随传质过程熵产率的增加而增加;当质量流与热流之间反相位时,两者的相位差越大,流动换热的强度越大,它反映正熵产率的自发过程与负熵产率的非自发过程之间的能量转换的热力学耦合机制,且传热过程熵产率随传质过程熵产率的增加而减小。质量流与热流之间由同相位到反相位,分别对应着场协同时的能量传递机制及热力学耦合时的能量转换机制,共同反映了体系流动换热时能量的最小耗散原理。The heat flow divergence equation is derived to reveal the inherent thermodynamic mechanism for enhancing convective heat transfer. It is found that the two mechanisms, in the case that heat and mass transfer processes are both spontaneous progresses, when mass flow and heat flow are in the same phase, the decreasing of phase difference between mass flow and heat flow, the increasing of heat transfer, which reflects field synergy mechanism of energy transfer between two spontaneous progresses with positive entropy generation rate, while in the case that heat transfer is nonspontaneous process and mass transfer is spontaneous process, when mass flow and heat flow are in the opposite phase, the increasing of phase difference between mass flow and heat flow, the increasing of heat transfer, which reflects the thermodynamic coupling mechanism of energy conversion between spontaneous process with positive entropy generation rate and nonspontaneous process with negative entropy generation rate. Between mass flow and heat flow from the same phase to the opposite phase, corresponding to the energy transfer mechanism of field synergy and the energy conversion mechanism of thermodynamic coupling.

关 键 词：流动换热 散度方程 场协同 热力学耦合 

分 类 号：TK124[动力工程及工程热物理—工程热物理]