大型结冰风洞中冰晶热/力平衡特性数值研究

为明晰大型结冰风洞中冰晶热/力平衡特性,发展了基于欧拉法的冰晶运动和传热传质耦合计算方法,模拟了典型大型结冰风洞构型内冰晶运动和传热过程,从沉降收缩、动量平衡和热平衡三个方面,考察了颗粒形状和体积密度的影响.结果表明:颗粒形状和体积密度对小尺寸冰晶的热/力平衡特性无显著影响.降低颗粒球形度和体积密度会抑制大尺寸冰晶沉降...

Numerical investigation of thermal and mechanical equilibrium characteristics of ice crystal in large icing wind tunnel

In order to understand the thermal and mechanical equilibrium characteristics of ice crystal in large icing wind tunnel，a numerical approach based upon the Eulerian method coupling movement and heat and mass transfer of ice crystal was developed to simulate the process of movement and heat transfer of ice crystal in the typical configuration of China Aerodynamics Research and Development Center icing wind tunnel.The effects of particle shape and bulk density were examined from three aspects of sink and contraction，momentum equilibrium and thermal equilibrium.Results showed that the particle shape and bulk density had no significant effects on the thermal and mechanical equilibrium characteristics of small size ice crystals.Decreased particle sphericity and bulk density could restrain the sink and contraction of large size ice crystals，thereby increasing the ice crystal cloud size at the exit of configuration.The decrease in particle sphericity and bulk density could increase the particle modified drag coefficient and modified Nusselt number，and then enhance particle momentum and thermal followability，thereby facilitating large size ice particles approaching the momentum equilibrium and thermal equilibrium states at the exit.Under typical computational conditions with large size ice crystal，the velocity and temperature differences of spherical particle at the exit of configuration were about 21 m/s and 8.6 ℃，while those of plate-shaped particle with low bulk density reduced to about 1 m/s and 5.8 ℃，respectively.