机构地区: 青岛大学师范学院
出 处: 《华北电力大学学报(自然科学版)》 2004年第6期20-23,共4页
摘 要: 审视了强化换热及其优化设计换热系统的方法,无论是传统的强化换热方法还是场协同方法,都只片面地强调了强化传递强度而忽视了由于强化所引起的能量耗散的约束。在强化传递强度的层次上,给出了换热强度与流体中内场和外场的数学关系,通过协调不同驱动力之间的关系可以强化热传递强度。在优化设计换热系统的层次上,给出了优化设计的热力学判据,表明了不可逆性与推动力之间的权衡,并由此得到换热器强化的优化设计温差。 The approaches to heat transfer enhancement, whether they are traditional or field-synergic, onlyemphasize the intensity of heat transfer unilaterally, and ignore the restriction of energy destruction caused by heattransfer enhancement. On the levels of intensity of enhancing heat transfer, a mathematical relationship betweenthe intensity of heat transfer and the internal field as well as external field in the fluids is given, which shows thatthe intensity of heattransfer can be controlled by adjustingthe relationship between differentkinds of driving forces.On the levels of optimum design of heat transfer systems, a thermodynamic criterion for optimum design of heattransfer units is proposed, which indicates the trade-off between irreversibility and driving forces. Further theoptimum temperature difference for design of heat exchanger is obtained.
关 键 词: 换热系统 换热强化 优化设计 换热器 传热性能
领 域: [动力工程及工程热物理]