Role of wheel and underbody aerodynamics of vehicle in the formation of drag forces is detrimental to the fuel (energy) consumption during the course of operation at high velocities. This paper deals with the CFD simulation of the flow around the wheels of a bus with different wheel housing arrangements. Based on benchmarking, a model of a bus is selected and analysis is performed. The aerodynamic drag coefficient is obtained and turbulence around wheels is observed using ANSYS Fluent CFD simulation for different combinations of wheel-housing- at the front wheels, at the rear wheels and both in the front and rear wheels. The drag force is recorded and corresponding influence on energy consumption of a bus is evaluated mathematically. A comparison is drawn between energy consumption of bus body without wheel housing and bus body with wheel housing. The result shows a significant reduction in drag coefficient and fuel consumption.

Electric vehicle works on stored energy inside the batteries or cells. These units needs to be regulated by cool down or heat up to perform utmost. This temperature regulation also ensure individual battery or cell life. BCS are installed on vehicles to regulate the temperature around battery packs. To ensure maximum performance of these units, numerical simulation is performed and detailed optimization of flow rate as well as flow path into BCS is carried out. All the parts are assembled inside the unit as per defined packaging area or size. Numerical modelling (CFD) is performed to examine the flow path. Flow path is very important to examine, as BCS units consists of condenser. It is very important for condensers to perform efficiently, which means air flow should happen across it appropriately. If sufficient flow is not happening across the condenser, then performance of condensers comes down and optimum temperature around battery packs cannot be maintained. This will affect the performance of battery pack capacity as well as individual battery life. Based on results obtained from…

Engine performance significantly depends on the effective exhaust of the combustion gases from the muffler. With stricter BSVI norms more efficient measures have to be adopted to reduce the levels of emissions from the exhaust to the atmosphere. Muffler along with reducing the engine noise is intended to control the back pressure as well. Back pressure change has a significant effect on muffler temperature distribution which affects the NOx emission from the exhaust. Many research communications have been made to reduce the exhaust emissions like HC, CO and CO2 from the exhaust by using different generation biofuels as an alternative fuel, yet they have confronted challenges in controlling the NOx content from the exhaust.This work presents the combined effect of Muffler geometry modifications and blended microalgal fuel on exhaust performance with an aim to reduce NOx emission form a four-stroke engine. In this exertion, the computational fluid dynamics model is developed to analyze the effect of muffler geometry modification on vital exhaust parameters of an engine. The engine is powered with a blend of chlorella…

While advanced automotive system assemblies contribute greater value to automobile safety, reliability, emission/noise performance and comfort, they are also generating higher temperatures that can reduce the functionality and reliability of the system over time. Thermal management and proper insulation are extremely important and highly demanding for the functioning of BSVI and RDE vehicles. Frugal engineering is mandatory to develop heat shield in the exhaust system with minimum heat loss. Heat shield design parameters such as insulation material type, insulation material composition, insulation thickness, insulation density, air gap thickness and outer layer material are studied for their influences on skin temperature using mathematical calculation, CFD simulation and measurement. Simulation results are comparable to that of the test results within 10% deviation. The performance index is calculated using the temperature gradient between the pipe surface and the external skin temperature. The performance index increases with material insulation thickness and insulation material density. Increase in insulation thickness from 6 mm to 19 mm reduces the skin temperature from 44% to 77%. The specialty insulation material provides a high…

Aerodynamic packages can provide a significant performance benefit to Formula SAE cars, but design and development of a full aerodynamics package can be time-consuming and expensive. An undertray system can provide significant aerodynamic benefits at a lower cost than a full aerodynamics package with front and rear wings. To properly design and test an undertray, a robust program of computational fluid dynamics (CFD) analysis and verification is needed. CFD analysis can be challenging, especially for large external flow problems like that of a full car. Due to this difficulty, careful meshing and setup of simulations is necessary to ensure accurate results. Much like analysis, fabrication of an aerodynamics package for a Formula SAE car is difficult. Fiberglass and carbon fiber layup processes are commonly used, but are prone to a variety of issues, and can be costly and time-consuming. Therefore, a thorough layup schedule and a careful manufacturing process is necessary. Fiberglass and carbon fiber were chosen as materials for the undertray due to their low weight relative to strength. These materials are often difficult…

This article discusses an approach to simulating a generic idealized car model (Ahmed body) moving in close proximity to a side-wall, using a transient Computational Fluid Dynamics (CFD) method. This phenomenon is very important in motorsports, where racing close to the safety barrier is common. Driving in close proximity to a side-wall alters the aerodynamic characteristics of the vehicle significantly; however, only a handful of published works exist in this area. Additionally, the experimental studies conducted in the past suffer from certain inadequacies, especially in terms of simulating the side-wall. This casts some uncertainty as to the relevance of these studies to the real-world problem. The present study attempts to imitate the real-world flow phenomenon by taking a nontraditional CFD approach of translating the body relative to the stationary surrounding fluid and side-wall instead of the classical method of flowing air over a stationary vehicle model. This was achieved by using a relatively new and computationally efficient meshing technique for overlapping grids called the “Overset” or “Chimera” mesh. The initial task was to accurately predict…

Aerodynamic optimization of the exterior vehicle shape is a highly multidisciplinary task involving, among others, styling and aerodynamics. The often differing priorities of these two disciplines give rise to iterative loops between stylists and aerodynamicists. Reduced-order modeling (ROM) has the potential to shortcut these loops by enabling aerodynamic evaluations in real time. In this study, we aim to assess the performance of ROM via proper orthogonal decomposition (POD) for a real-life industrial test case, with focus on the achievable accuracy for the prediction of fields and aerodynamic coefficients. To that end, we create a training data set based on a six-dimensional parameterization of a Volkswagen passenger production car by computing 100 variants with Detached-Eddy simulations (DES). Based on this training data, we reduce the dimension of the solution space via POD and interpolate the base coefficients with Kriging (aka Gaussian Process Regression) for predictions of the flow field at unseen parameter combinations. The error analysis of the fields and drag coefficient predictions reveal that 100 training samples are sufficient for this six-dimensional test case in…