محاسبه ضريب نيروي مقاوم اجسام محدب در جريان ملكولي آزاد و مطالعه اثر پارامترهاي مختلف بر آن

Calculation of Drag Force of A Convex Body in Free Molecule Flow Regime

The drag force imposed on a convex body in a free molecule regime flow together with corrections of the atmosphere model is investigated in the present study. Convex simple bodies such as a sphere and a cone and bodies with combination of these are modeled using the softwares Solidworks and ANSYS. The drag force of the mentioned bodies are obtained and compared with the data reported in literature. The HSN model for gas-surface interaction modeling is introduced as well. A computer code for drag force calculations is written. The results obtained using this program are in good agreement with the experimental results of other investigators. This indicates that variation of R-value of the air cannot be neglected. The drag force results obtained by HSN model have lower values in comparison to the standard Nocilla model.