内翅板蒸发式冷凝器降膜流动与传热特性  

Characteristics of Falling Film Flow and Heat Transfer in Internal Fin-plate Evaporative Condenser

作　　者：龚毅[1] 刘旭[1] 杨雅浓 吴学红[1] 赵敏[1] 

机构地区：[1]郑州轻工业学院能源与动力工程学院,郑州450002

出　　处：《制冷学报》2016年第4期20-26,共7页Journal of Refrigeration

基　　金：国家自然科学基金(51476148)资助项目~~

摘　　要：为了增强蒸发式冷凝器板外气液两相流动与传热,基于数值模拟方法对比分析了几种新型的板片结构,研究了板片构型、喷淋水喷淋密度、空气入口速度等因素对气液两相流流体流动及传热性能的影响。结果表明：半圆波纹板有较长的水膜稳定时间和较大的换热面积,换热性能较好;不同板片结构的蒸发式冷凝器具有不同的最佳喷淋水喷淋密度,最佳喷淋密度区间范围为0.48-0.93 kg/（m·s）;空气入口速度一定时,半圆波纹板的壁面温度随喷淋密度增大而增大,气液界面温度随喷淋密度增大而减小;当空气入口速度小于2.5 m/s时,空气入口速度的适当增大能够有效减薄半圆波纹板板外水膜厚度,强化换热。In order to improve the heat transfer and fluid flow performance of external gas-liquid two phase flow of plate in the evaporative condenser, the new surfaces of plate are comparatively analyzed. The effect of the different kinds of surface structure, spray density of water and air inlet velocity on the characteristics of gas-liquid two-phase flow and the performance of heat transfer are investigated. The results show that ： the semicircle wavy plate has longer time of water film forming and larger heat transfer area and better performance of heat transfer; different plate structures of the evaporative condenser have different optimal spray density of spray water, and the optimal spray density are from 0.48 kg/m · s to 0.93 kg/（ m · s） ; when the air inlet velocity is constant, the wall temperature of semi-circle wavy plate is increased and the temperature of gas-liquid interface is decreased with the increasing of spray density; when the air inlet velocity is less than 2.5 m/s, the increasing air inlet velocity can effectively reduce thickness of water film of external semicircle wavy plate and enhances heat transfer.

关 键 词：蒸发式冷凝器 半圆波纹板 喷淋密度 强化换热 

分 类 号：TK172[动力工程及工程热物理—热能工程] TK124