Sharif Digital Repository

The objective of this study was to propose a new analytical model for studying response of head impacts. Head is modeled by fluidfilled ellipsoidal shell of inconstant thickness impacted by a solid elastic sphere. Modeling the head as an ellipsoid is more realistic than modeling it as a sphere, the previous model existing in the literature [3]-[8]. In this model, the effect of Hertzian contact stiffness and local shell stiffness are combined to derive explicit equations for impact duration, the peak force transmitted to head, and the head injury criterion. One of the advantages of the model presented is sensitivity to the site of impact. A comparison between the present analytical results... 

This paper describes an integrated engineering approach for a mathematical modeling of an automotive air-conditioner system and method for performing heating and cooling load calculations of a vehicle shell assembly for designing an HVAC system for a passenger vehicle. In addition, there is presented a physical optimization technique based on minimization of the total entropy generation for the vehicle air-conditioner and HVAC system. Simultaneous solution of the automotive air-conditioning, air handling and the passenger cabin thermal model provide the transient temperature history for consideration of passenger comfort conditions. The validity of the mathematical model was confirmed using...