システム天井用吹出口の吹出気流性状に影響を与える要因の整理と非構造格子系CFD解析による検討: 空調用吹出口のCFDモデリングのための吹出気流データの整備とその適用（その1）

摘要

室内気流分布を特徴づける重要な要因のひとつとして、吹出気流rn性状が挙げられる。特に、アネモスクット型吹出口と呼ばれる多層rnコーン型吹出口などでは吹出口周辺の乱流構造が非常に複雑になり、rnこのような吹出口を設けて空調を行う事務室空間の温熱・空気環境rnを数値流体解析（以降、CFD解析と記す）により検討するには、吹出rn口周辺の吹出気流性状を再現することが重要である。%Computational Fluid Dynamics (hereafter, CFD) is one of the most useful techniques to predict the airflow distribution in air-conditioned and ventilated rooms. The previous studies show that the prescribed velocity method (hereafter, P. V. method) is effective to simulate complicated airflow from an air diffuser in CFD. However, the velocity distribution in the vicinity of the air diffuser as boundary conditions of coarse gird CFD using P. V. method can be affected by the airflow rate, the connecting conditions of the diffuser and supply air duct, and the buoyancy effect due to the temperature distribution. In this paper, the development of the versatile airflow data for P. V. method and the method for its application are discussed. In the first study, the unstructured fine elements CFD simulations under isothermal condition are carried out and the obtained airflow distributions of the system ceiling air diffuser are compared. The relationship between the airflow rate and the velocity near the diffuser, the influence of connecting conditions of the diffuser and air duct are confirmed by the comparison of CFD results. In the second study, the influence of the buoyancy near the diffuser is compared to the inertial force of discharged air on the basis of local Archimedes number obtained by the unstructured CFD simulations under non-isothermal condition.