摘要
为适应工程应用中快速、准确模拟室内空气流动的需要,提出N点风口动量模型,以简化描述利用计算流体动力学CFD方法模拟室内空气流动时百叶、多孔板类送风口的入流边界条件。百叶和多孔板风口的等温自由射流算例以及HESCO孔板类散流器在室内送风的算例和实验数据对比表明,N点风口动量模型可以较好地解决数值模拟室内空气流动的风口入流边界条件描述问题。
To simulate indoor airflow more quickly in order to get satisfied results for engineering projects, a new approach called N-point momentum model is proposed to describe boundary conditions of air terminal devices in the computational fluid dynamics (CFD) calculation. The new air supply opening model (ASOM) directly and exactly describes inlet boundary conditions, modeling inlet mass, momentum and buoyancy flow rates. It modifies the source term of momentum equations in CFD program to ensure correctly mass and momentum inflow rates without separately describing the boundary conditions of continuity and momentum equations. Not like some other methods of describing diffuser boundary conditions, the N-point momentum model need not measurement, which makes its application easy. Furthermore, as the N-point momentum model docs not rely on empirical formulas, it can be used for any actual case. To test the accuracy of the ASOM for modeling inlet boundary conditions, all the validation cases are isothermal, as the simulated results of isothermal indoor airflow may not be affected by other factors. Many researchers have pointed out that the k-Ε turbulence model is proper for simulating the isothermal indoor airflow. Therefore, the isothermal free air jets from grille and perforated panel, which are commonly used in air-conditioning and ventilated rooms, are studied by the N-point momentum model and k-Ε turbulence model. Furthermore, the airflow in a room ventilated by a HESCO diffuser is also simulated. Comparing the calculated results with the measured data, it is evident that the new ASOM can model inlet boundary conditions of diffusers quickly and correctly. It can be concluded that the new approach is proper to describe complicated inlet boundary conditions of indoor airflow simulation.
出处
《计算力学学报》
EI
CAS
CSCD
北大核心
2003年第1期64-70,共7页
Chinese Journal of Computational Mechanics
