Mecânica dos Fluidos: Acesso Aberto

Air Flow Regimes and Thermal Comfort in Vehicle Cabin Considering Solar Radiation

Abstract

Ibrahim Reda, Essam E. Khalil, Taher M. Aboudeif , Ahmed El Degwy

Thermal comfort in vehicle cabin can affect drivers and passenger’s health, performance and comfort. Due to spatial and temporal variation of state variables and boundary conditions in the vehicle cabin , the heating, ventilating and air-conditioning (HVAC) does not have to be designed to provide a uniform environment, especially because of individual differences regarding to physiological and psychological response, clothing insulation, activity, air temperature and air movement preference, etc. The main objective of this research is to study the air flow regimes and thermal comfort in vehicle cabin using computational fluid dynamics (CFD) software. For this purpose, the CFD software from ANSYS Inc., called FLUENT 17.2, is employed. In which the solar load model is embedded s2s (surface to surface) as a solar radiation model. The CFD modeling techniques solved the continuity, momentum and energy conservation equations in addition to standard k – ε model equations for turbulence closure (The use K-epsilon turbulence mode was recommended as it had been widely tested and investigated in the seventies of last century). Meshing is processed around 4.0 million unstructured tetra-elements approximately. The performance of the air conditioning system is characterized by airflow regimes (air temperature, air velocity, relative humidity, PMV and PPD contours), the present work is focus on the effect of air terminal shape of Hvac system, two configurations are used case (1) and case (2). Case (1) is the existing design of air terminals of the Hvac system of the selected car (Skoda Superb), the air terminals are in rectangular shape. While case (2) are in circle shape