Computational Fluid Dynamics Analysis of the Effects of Windshield Angle on Fuel Economy and Optimization for the Locally Assembled Anbessa Intercity Bus

Abstract

Anbessa Intercity Bus Has Very Poor External Body Shape, And Hence Has Very High Aerodynamic Drag That Significantly Increases Its Fuel Consumption. Various Works Have Been Done To Improve Fuel Economy Through Reduction Of Drag Coefficients Using Optimized Windshields. Though, Still, Various City Buses Have Suboptimal Aerodynamic Design, Primarily Owing To Their Vertical Rectangular Windshield Configuration. And, This Suboptimal Design Results In High Aerodynamic Drag, Significantly Increasing Fuel Consumption. One Of Such City Buses Is Anbessa City Bus. However, By Reducing The Windshield Angle, The Drag Force Can Be Minimized, Resulting In Improved Fuel Economy. Thus, This Compares Six Bus Models With Varying Windshield Angles, Ranging From 19?? To 45?? Using The Phoenics Software. It Is Found That As The Windshield Angle Increases, The Drag Coefficient Decreases, Leading To Improved Fuel Efficiency. Specifically, The Model With The Lowest Windshield Angle Of 19?? Exhibits The Highest Drag Coefficient And The Lowest Fuel Economy, While The Optimized Model Of The Bus Which Has Highest Windshield Angle Of 38.068o, Has The Lowest Drag Coefficient And Highest Fuel Economy.Further more, The Optimization Is Performed Using Design Expert Software To Obtain The Optimized Model With Desirability Factor Of 0.886 Is To Give A Windshield Angle Of 38.068o At Which Drag Coefficient, Lift Coefficient, And Fuel Economy Are 0.53, -0.07, And 5.967Respectively. While Determining These Values The Calculation For Drag Coefficient, Lift Coefficient, And Fuel Economy Obtains The R2 Value Of 0.8727, 0.9375, And 0.9999, Respectively. Thus, By Increasing The Windshield Angle By 19.1o, The Fuel Economy Can Be Improved By32.6%.