en ارتعاشات Vibration, noise, Acoustic پژوهشي Research <table align="center" class="MsoTableGrid" style="border-collapse:collapse; border:none"> <tbody> <tr> <td style="width:407px; padding:0in 7px 0in 7px; height:90px" valign="top"><span style="font-size:11pt"><span style="line-height:115%"><span style="font-family:Calibri,sans-serif"><span style="font-size:10.0pt"><span style="line-height:115%"><span new="" roman="" style="font-family:" times="">This study employs two-dimensional CFD simulations to analyze how rear slant angle and inter-vehicle spacing dictate aerodynamic drag in a tandem Ahmed body configuration. We systematically evaluated slant angles from 15&deg; to 45&deg; and longitudinal spacings from X/L = 0.1 to 0.5. The results delineate three distinct aerodynamic regimes for the trailing vehicle: a drafting zone at close distances (X/L=0.1) with significantly reduced drag, an interference zone (X/L=0.2-0.3) where drag peaks, and an independence zone (X/L>0.4) where vehicles behave aerodynamically isolated. Furthermore, the model successfully captures the critical drag rise as the slant angle surpasses 30&deg;, a key flow transition. While the simulation over-predicts absolute drag values, which is an expected outcome of the 2D approach, it demonstrates high fidelity in capturing complex trends, providing foundational insights for optimizing vehicle platooning strategies.</span></span></span></span></span></span></td> </tr> </tbody> </table> Ahmed Body, Inter-Vehicle Spacing, Drag Coefficien,t Wake Interaction, Y⁺ distribution, CFD 4966 4979 http://ase.iust.ac.ir/browse.php?a_code=A-10-884-1&slc_lang=en&sid=1 Ata Ahmadabadi Asle Alamdari ataalamdari1997@gmail.com 180031947532846005311 180031947532846005311 No Hamed Chehrmonavari h_chehrmonavari@auto.iust.ac.ir 180031947532846005312 180031947532846005312 No Amirhasan Kakaee kakaee_ah@iust.ac.ir 180031947532846005313 180031947532846005313 Yes