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The reliability of engine valve springs is a very important issue from the point of view of warranty. This paper presents a combined experimental and statistical analysis for predicting the fatigue limit of high tensile engine valve spring material in the presence of non-metallic inclusions. Experimentally, Fatigue tests will be performed on valve springs of high strength material at different stress amplitudes. A model developed by Murakami and Endo, which is based on the fracture mechanics approach, Extreme value statistics (GUMBEL Distribution) and Weibull Distribution will be utilized for predicting the fatigue limit and the maximum inclusion size from field failures. The two approaches, experimental and theoretical, will assist in developing the S-N curve for high tensile valve spring material in the presence of non-metallic inclusions.

An ergonomics study was conducted in a mock-up with a fixed steering wheel position. Drivers adjusted the seat and pedals to a comfortable position. A three-dimensional coordinate measurement machine (CMM) was used to measure the comfortable position of 21 participants. Proven test methods were used to collect the posture data. A model is described to assist in seat and pedal placement for cockpit design.

In this experimental work, a flow field test system embedded with different vortex generators was installed to investigate the impact of vortex generation on heat transfer of air flow in a horizontal channel, and the flow structure was evaluated using a particle image velocimetry (PIV) system. Three different configurations of vortex generators were fitted vertically on a flat plate, at attack angles of 15o, 30o, and 45o, and tested at four different incoming air velocities. An axial fan was used to supply the flow of air through the test section. The effects of Reynolds number, attack angle, and the shape of vortex generators were examined in this work. The experimental results showed that, the presence of vortex generators had considerable effect on temperature distribution, pressure drop, and heat transfer augmentation in the channel flow.

The power and torque output of an engine (for a Formula SAE vehicle) can be dramatically improved through good intake design. For example, performance can be improved by reducing pressure losses in the intake system, or by improving the restrictor's design to increase airflow at lower pressure drops. A plenum design with equal air distribution to all cylinders can also be helpful. In this study, four different intake designs were tested on a dynamometer and the power outcomes were compared. Based on theory and lab testing and intake system was designed to optimize throttle response as well as low-end torque; a steady flow of air passes through the throttle body and the restrictor and then into the plenum. Dynamometer testing confirmed an overall increase in torque and horsepower compared to earlier designs.

This work studies an optimization tool for 2D and 3D a multi-element airfoil which utilizes the power of CFD solver of a Shape Optimizer package to find the most optimal shape of multi-element airfoil as per designer's requirement. The optimization system coupled with Fluent increases the utilization and the importance of CFD solver. This work focuses on combining the high fidelity commercial CFD tools (Fluent) with numerical optimization techniques to morph high lift system. In this work strategy we performed morphing (grid deformation) directly inside the Fluent code without rebuilding geometry and the mesh with an external tool. Direct search method algorithms such as the Simplex, Compass, and Torczon are used; Navier-Stokes equations were solved for turbulent, incompressible flow using k-epsilon model and SIMPLE algorithm using the commercial code ANSYS Fluent.

Longitudinal vortex generation is a common technique for enhancing heat transfer performance. It can be achieved by employing small flow manipulators, known as vortex generators (VGs), which are placed on the heat-transfer surface. The vortex generators can generate longitudinal vortices, which strongly disturb the flow structure, and have a significant influence on the velocity and temperature distributions, causing improved thermal transport. In this work, numerical simulations are conducted for a horizontal rectangular channel with and without a pair of longitudinal vortex generators. The vortex generators are fitted vertically on the bottom surface of the channel. The Computational Fluid Dynamics (CFD) analysis aims to acquire a better understanding of the flow structure and heat transfer mechanisms induced by longitudinal vortex generation. The simulation is performed using ANSYS Fluent, and three flow inlet velocities are considered: 1.38 m/s, 1.18 m/s, 0.98 m/s.

Traction control is an electronic means of reducing the wheel spin caused by the application of excessive power for the valuable grip. Wheel spin can result in loss control of the car, reduce acceleration and cause tire wear. In the front wheel tire the loss grip is experienced as underwater, where the front of the car ‘pushes’ forward, not turning as much as the driver has exposed by turning the tearing. In the rear wheels slip causing oversteer, where the rear of the car swings around, turning much sharper than the driver anticipated. The result of all these problems is that the driver starts loosing control of the vehicle, which is undesirable. With the new design of the Traction Control System, the amount of the wheel slippage is precisely controlled. In racing, this means corner can be taken constantly quicker, with system applying the maximum power possible while the driver remains in total control.

Thermal management systems (TMS) of armored ground vehicle designs are often incapable of sustained heat rejection during high tractive effort conditions and ambient conditions. During these conditions, which mainly consist of high torque low speed operations, gear oil temperatures can rise over the allowable 275°F limit in less than twenty minutes. This work outlines an approach to temporarily store excess heat generated by the differential during high tractive effort situations through the use of a passive Phase Change Material (PCM) retrofit thereby extending the operating time, reducing temperature transients, and limiting overheating. A numerical heat transfer model has been developed based on a conceptual vehicle differential TMS. The model predicts the differential fluid temperature response with and without a PCM retrofit. The developed model captures the physics of the phase change processes to predict the transient heat absorption and rejection processes.

Strict regulations exist in different countries with respect to vehicular emissions by their respective government bodies requiring automakers to design fuel-efficient vehicles. Fuel economy and carbon emission are the main factors affecting these regulations. In this competitive industry to make fuel efficient vehicles and reduce Green House Gas (GHG) emissions in internal combustions has led to various developments. Exhaust Heat Recovery System (EHRS) plays a vital role in improving powertrain efficiency. In this system, heat rejected by the engine is reused to heat the vehicle fluids faster (for example, engine coolant, engine oil, etc.) correspondingly reducing harmful gas emissions. In internal combustion engines, generally only 25% of the fuel energy is converted into useful power output and approximately 40% of it is lost in exhaust heat. Certain studies show that by using the EHRS, the power output can be increased to 40% and the heat loss can be reduced to as much as 25%.