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. Keywords: Wheel-housing, Drag Coefficient, CFD Simulation, Bus, Energy consumption

Engine performance significantly depends on the effective exhaust of the combustion gases from the muffler. With stricter BSVI norms more efficient measures has to be adopted to reduce the levels of exhaust 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 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 alternate fuel, yet they have confronted challenges in controlling the NOx content from 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 from the exhaust of a four-stroke engine. In this exertion, 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 blend of microalgae…

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…

In the present work, it is aimed at developing an integrated approach for combustor modeling involving rapid prototyping and water tunnel testing to assess the cold flow numerical simulations; the physical model will be subjected to cold flow visualization and parametric studies and CFD analysis to demonstrate its capability for undergoing rigorous cold flow testing. A straight through annular combustor is chosen for the present study because of it has low pressure drop, less weight and used widely in modern day aviation engines. Numerical Analysis has been performed using ANSYS-FLUENT. Three dimensional RANS equations are solved using k-ɛ model for the Reynolds numbers ranging from 0.64 x 10^5- 1.5 x 10^5 based on the annulus diameter. Post processing the results is done in terms of jet penetration, formation of re-circulation zone, effective mixing, flow split and pressure drop for different cases. Physical combustor models are fabricated using Rapid prototyping with Poly Lactic Acid material and approximated 2D combustor model is used for capturing important flow patterns using high speed camera in 2D water tunnel, and…

The present study provides a detailed investigation on simulation of Copper oxide nanofluids in a simple horizontal circular pipe considering turbulent forced convection, with a constant heat flux boundary condition. The simulation is carried out using three different models available in fluent viz. Newtonian single phase model, Eulerian-mixture and Eulerian-Eulerian multiphase models. The Reynold number of the flow is varied along with volume concentration of nanoparticles varying from low to high. Nanofluids rheology is studied by considering standard k-ε two equation turbulence model with enhanced wall treatment considering appropriate wall y+ values. The effective temperature dependent thermo-physical properties for nanofluids were seized from the literatures. The results from the simulation clearly showed an increase in the heat transfer characteristics with the addition of nanofluids compared to that of base fluid alone. Eulerian-Mixture model predicted the Nusselt number near to that of the experimental results from literature. Index terms: Nanofluids, copper oxide, heat transfer, simulation, Nusselt number.

The outside visibility through the windshield and Outer Rear View Mirror (ORVM) visibility through the side glasses are critical for safe driving. The frost deposition on the Windshield and side glasses in the cold climatic condition impairs the outside and ORVM visibility during driving and hence leads to an unsafe driving condition. In India, the regulation AIS-084 governs the defrosting standard. The defrosting performance evaluation by testing cannot be performed at concept stage when the vehicle prototype is not available. It also increases the cost of vehicle development due to increase in the number of prototype used for Testing. This paper explains about the in-house developed CFD methodology to evaluate the windshield defrosting performance of the vehicle in the concept stage when no Vehicle proto is available and cost of improvement countermeasure for defrosting performance is very less. This methodology is implemented for some of the existing models. The results of CFD simulations were compared to the experimental data using a correlation study and the correlation coefficient of numerical and Experimental measurements were reported. CFD…

Noise of almost every form is considered undesirable and hence its reduction is an important area of study. Aerodynamically generated noise due to vortex shedding in the wake of bluff bodies is a major source of such undesirable noise in applications involving overhead wires, poles, automotive components and aircraft landing gears. Vortex suppression methods are employed in these cases to reduce the noise generated by suppressing the pressure fluctuations arising near the bluff body surface. For the present study, flow past different bluff bodies is simulated using commercial CFD software, ANSYS FLUENT, with and without involving suppression methods. The calculations for flow field are performed by solving the two-dimensional governing equations for unsteady isothermal incompressible viscous flow. Turbulence modelling is performed using Large Eddy Simulation (LES) with Smagorinsky-Lilly subgrid model. Simulations for far-field noise are carried out using Ffowcs-William and Hawking model and different aeroacoustic parameters like overall sound pressure level and sound pressure level are computed for different receiver locations. The effectiveness of different suppression methods is tested at different Reynolds numbers and their…

The present numerical analysis aims at studying the effect of changes in profile of van on aero-acoustic noise and aerodynamic drag. The numerical analysis is carried out using commercial CFD software, ANSYS Fluent, with k-e & Large Eddy Simulation turbulence models. In present study four models of truck were analysed, including baseline model at different Reynolds numbers, namely 0.391, 0.415 and 0.457 million. In order to reduce the aero-acoustic noise, various profile modifications have been adapted on existing van model by adding a top and bottom diffuser at the rear of the truck. The comparison has been done with respect to coefficient of drag, coefficient of pressure, pressure contours, velocity vectors and streamline between all four cases. It is observed from the simulation results among different modifications of truck, adding a top and bottom diffuser of 15 degrees at the rear end of truck gives the maximum reduction in aero-acoustic noise upto 9.4% and aerodynamic drag reduction of 3.8 % as compared to baseline model, at a speed of 81 km/h.

CFD simulations are effectively used to cut down the vehicle development period and to completely understand the interaction between the cabin thermal comfort and mobile air-conditioning system. While the methodologies are well established to quantify the passenger thermal comfort behavior in a vehicle, the investigations to quantify the cabin airflow directivity still requires in depth understanding, even though a vast number of studies are available on cabin cool down performance. The air velocity achieved at driver and passenger aim point is one of the key parameter to evaluate the automotive air-conditioning performance. The design of duct, vent and vanes has a major contribution in the cabin air flow directivity. However, visual appearance of vent and vane receives higher priority in design because of market demand than their performance. More iterations are carried out to finalize the HVAC duct assembly until the target velocity is achieved. The current process is time consuming as the vanes are rotated manually and simulation is done for each vane angle and requires post process for every iteration. It requires more…

Design and analysis of De-laval restrictor with throttle body for formula Vehicle Dr Soundararajan SKECT , Mr. Pradeep C, Force Motors , Mr. Ashwin Sriram, SKECT. Abstract Restrictor is a component which controls the mass flow of air passing to the engine. The proposed work focuses on design and analysis of air intake restrictor of Duke 390cc engine which is used in formula vehicles. As a constraint of this system, the air flows through a single circular throat of diameter 20mm. In past decades conventional venturi nozzles were used as a restrictor but it leads to nominal press drop. The main objective is to utilize De-Laval Nozzle for the minimal pressure drop. The change in pressure will increases the engine power output. The analysis is done by varying design conditions such as three levels of convergent (12,14 and 16 degree) and three levels of divergent angles (4, 6 and 8 degree) are taken into consideration. After numerous CFD Simulations it is inferred that the optimal angles of 14 and 4 degree for convergent and divergent…