摘要
以柴油发动机燃烧室内喷雾油滴撞壁为研究对象,运用计算流体力学软件FLUENT,基于流体体积法(VOF),建立了高温柴油液滴撞击低温球形不锈钢壁面的数值模型,对撞壁过程流动及传热特性进行了研究,并对模型进行了实验验证。研究表明:柴油液滴撞击亲油性球形壁面后铺展系数随时间递增,一段时间后保持为恒定值;壁面热流密度在液滴与壁面接触区域内呈现不均衡分布,且数值随时间递减;液滴直径、撞壁速度对撞壁特性有影响,这两个因素均与铺展系数和总壁面热流密度数值成正相关,但与达到最大铺展系数及最大总壁面热流密度的无量纲时间无关;速度超过临界值,油滴撞壁后将会产生飞溅及二次液滴。
Numerically modeled high temperature diesel spray droplet impacting on low temperature sphere surface of the spray combustion process in diesel engine based on volume of fluid method.Both the dynamic behaviors and heat transfer of the impact process were studied.The results can be concluded as follows：The diesel droplet spreads larger and finally becomes constant oil film attached to the lipophilic stainless spherical surface.The wall heat flux unevenly distributes on the spreading area and the value of it decreases with spreading time.Both the increases of impact velocity and droplet diameter can promote the increase of spreading coefficient,as well as the total wall heat flux,but they are not related to the dimensionless time.When the impact velocity reaches the critical value,the splash and second droplets will appear.
出处
《青岛科技大学学报（自然科学版）》
CAS
2016年第4期440-445,450,共7页
Journal of Qingdao University of Science and Technology:Natural Science Edition
基金
山东省自然科学基金项目(ZR2009FM056)
中央高校基本科研业务费专项资金资助项目(15CX06052A)
中国石油大学(华东)研究生创新工程基金项目(YCXJ2016051)
关键词
液滴撞壁
球面
撞壁特性
液滴直径
撞壁速度
数值模拟
droplet impact
sphere surface
impact characteristic
droplet diameter
impact velocity
numerical modeling
