圆柱凸台阵列壁面对液膜强化换热特性影响研究

Study on the Influence ofWall Array of Cylindrical Convex on Enhanced Heat Transfer Characteristics of Thin Film

为了探究圆柱凸台阵列壁面对液膜强化换热的影响,以水幕换热为研究对象,以液膜强化换热为研究基础,简化物理模型,以数值模拟的方式分别求解不同初速度下圆柱凸台阵列壁面水幕模型与平整壁面水幕模型的换热量,通过对比得出圆柱凸台阵列对液膜强化换热的增强作用,分析初速度与圆柱底圆直径对强化换热的影响。结果表明:在低流速范围内,加入了圆柱凸台阵列的水幕模型的换热明显被强化,当V_(0)=0.3 m/s时,仅在1 m的计算域内,圆柱凸台阵列水幕与平整壁面水幕的单次温差为0.605℃;入口速度V_(0)越小,圆柱阵列下游受圆柱绕流影响越明显,液膜作用越强,温升越大;若直径D越大,则水幕流动受圆柱绕流影响越大,水层加热越不均匀,温升越大。

In order to explore the wall array of cylindrical convex effect on the thin film enhanced heat transfer,this paper takes the water curtain heat exchange as the research object,based on the research of thin film enhanced heat transfer research,simplified physical model,in the form of numerical simulation,calculate the heat exchange between the cylindrical convex array wall water curtain model and the flat wall water curtain model at different initial velocities.Through comparison,the effect of the cylindrical lug array on the enhanced heat transfer of thin film is obtained,and the effect of the initial velocity and the diameter of the cylindrical bottom circle on the enhanced heat transfer is analyzed.The research results show that the water curtain model with cylindrical convex array is significantly strengthened in the range of low flow rate.When V_(0)=0.3 m/s,the temperature difference between the water curtain of cylindrical convex array and the water curtain of flat wall is 0.605℃in the calculation domain of only 1 m.The smaller the inlet velocity V_(0) is,the more obvious the influence of cylinder flow on the downstream of the cylindrical array is,the stronger the thin film action is,and the greater the temperature rise is.The larger diameter D is,the greater the influence of the water curtain flow around the cylinder is,the more uneven the water layer heating is,and the greater the temperature rise is.The research results lay a theoretical foundation for further research on the heat transfer characteristics of water curtain array based on thin film theory.