Fuel consumption and aerodynamic performance analysis of existing and modified locally manufactured buses using CFD

Abstract

Locally manufactured buses in developing countries are normally manufactured with minimum considerations regarding aerodynamic performance, thereby resulting in excessive drag forces, fuel consumption, emissions, and operating costs. Such issues have a substantial impact on the sustainability and economic viability of the bus transportation system. One of the main problems facing the automobile industry is the growing demand for vehicles that use less fuel and are more environmentally friendly. In order to determine whether drag reduction is possible, research on the aerodynamic design of locally produced buses is desirable. One of the locally produced bus models is chosen for optimisation, and attempt to lower CD by adding external features in addition to changing the front face, underneath the bus, and at the roof and tail. Model I is the present model and Model II is an adaption of the FSR (kitkite) bus. Numerical and experimental tests have been conducted in CFD and wind tunnel tests to prove the effectiveness of the modified result. Based on the numerical result of the drag reduction in per cent between the modified model and the existing bus, it is 29.84%, 27.47% and 26.07% at 80 km/h, 100 km/h and 120 km/h, respectively. Fuel saving for 100 km in litres (L) at 80 km/h, 113 km/h and 129 km/h is 3.08 L, 6.03 L and 7.88 L, respectively, between the locally manufactured bus and modified models, whereas the fuel reduction in % is 15.62, 19.84 and 21.18%, respectively.