非等温竖壁贴附射流通风墙体对流换热特性研究
Investigation of convective heat transfer characteristics in ventilated walls with non-isothermal vertical wall-attached jets
摘要：
非等温贴附射流夜间通风系统适用于昼夜温差小且室外静风率较高的夏热冬冷地区。由于夜间通风墙体的动态蓄放热特性,实际情景下墙体内壁面与射流气流之间存在温差,在温差驱动下受浮升力影响诱导形成热羽流,导致其对流换热特性有别于空调工况。本文采用实验与数值模拟相结合的研究方法,分别针对强迫对流和混合对流研究了非等温竖壁贴附射流通风墙体的对流换热特性。基于实验及模拟结果,通过回归分析,在既有的外掠平板强迫对流换热关联式和混合对流换热关联式基础上进行修正,建立了适用于竖壁贴附射流场景的强迫对流换热关联式和混合对流换热关联式。
Abstract：
The non-isothermal wall-attached jet nocturnal ventilation system demonstrates particular suitability for hot summer and cold winter zone exhibiting minimal diurnal temperature fluctuations and high outdoor static air rates. Due to the dynamic heat storage and release characteristics of the nocturnal ventilation wall, a temperature difference emerges between the interior wall surface of the wall and the adjacent jet flow in actual conditions. This thermal gradient initiates buoyancy-induced plume formation, resulting in its convective heat transfer characteristics being different from those of air conditioning environments. This study adopts a combined experimental and numerical simulation approach to investigate convective heat transfer characteristics in ventilated walls with non-isothermal vertical wall-attached jets under both forced convection and mixed convection scenarios. Based on experimental and simulation results, this paper employs regression analysis to revise the existing correlations for forced convection and mixed convection over flat plates, establishing the adapted correlations for the vertical wall-attached jet scenario.
Keywords:vertical wall-attached jet; nocturnal ventilation system; convective heat transfer; forced convection; mixed convection; correlation revision