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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%.

Today's strict fuel economy requirement produces the need for the cars to have really optimized shapes among other characteristics as optimized cooling packages, reduced weight, to name a few. With the advances in automotive technology, tight global oil resources, lightweight automotive design process becomes a problem deserving important consideration. It is not however always clear how to modify the shape of the exterior of a car in order to minimize its aerodynamic resistance. Air motion is complex and operates differently at different weather conditions. Air motion around a vehicle has been studied quite exhaustively, but due to immense complex nature of air flow, which differs with different velocity, the nature of air, direction of flow et cetera, there is no complete study of aerodynamic analysis for a car. Something always can be done to further optimize the air flow around a car body.

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.

Bearings are a major component in any rotating system. With continually increasing speeds, bearing failure modes take new unconventional forms that often are not understood. In high speed applications, rolling element forces and gyroscopic moments can be significantly high compared to the applied forces acting on a bearing. Such moments create a “driving” torque causing outer race to creep. In this paper a mathematical model for the dynamics of a rolling element in a high speed bearing is derived. Preload values counterbalancing the torque driving the outer race to rotate can be predicted from this model. An attempt to experimentally measure this torque using a specially designed apparatus with integrated strain gauge torque sensor is also described. Both model and experimental measurements are aimed at understanding, and therefore preventing bearing failures due to outer race (creep) rotations.

As the need for super high speed components (pumps, motors, etc) continue to grow rapidly, so does the need to make measurements at speeds higher than ever before. Bearings are a major component in any rotating system. With continually increasing speeds, bearing failure modes take new unconventional forms that often are not understood. Such measurements are impossible if bearings fail to perform. This paper will address the dynamic modes a bearing passes through and the potential failure modes associated with each. A review of the state of the art of current failure modes will be given, and then a hypothesis on some new failure modes associated with particular speeds will be discussion. The paper will also describe an apparatus that was designed especially to study these phenomena. Range of speed studied is 0- 60,000 rpm. Preliminary measurements indicated that this range breaks into three different zones: low (0-15,000 rpm), moderate (15,000-25,000 rpm) and high (25,000- 60,000 rpm).

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.

This paper discusses the uses of shape morphing/optimization in order to improve the lift to drag ratio for a typical 3D multi-element airfoil. A mesh morpher algorithm is used in conjunction with a direct search optimization algorithm in order to optimize the aerodynamics performance of a typical high-lift device. Navier-Stokes equations are solved for turbulent, steady-state, incompressible flow by using k-epsilon model and SIMPLE algorithm using the commercial code ANSYS Fluent. Detailed studies are done on take-off/landing flight conditions; the results show that the optimization is successful in improving the aerodynamic performance.

This work aims to numerically investigate the aerodynamic characteristics of a multi-element airfoil NACA 23012. The investigation was conducted through Computational Fluid Dynamics (CFD), using ANSYS FLUENT software. The Navier-Stokes equations were solved for turbulent, incompressible flow using k-epsilon model and SIMPLE algorithm. The study was carried out for both take-off / landing conditions and the results were compared to experimental data of the NACA 23012 from wind tunnel tests. The experimental and computational results for drag and lift coefficients match effectively up to pre-stall attack angles. The pressure coefficients, velocity distribution, and wall Y+ data were presented for different angles of attack (0 deg, 4 deg, and 8 deg). The CFD analysis could help acquire a closer and detailed understanding of airfoil performance, which is usually not easy through normal experimentation.

In order to achieve optimum performance from an engine a homogeneous air fuel mixture must enter the combustion chamber. There are a number of factors that affect the mixture; this study focuses on the flow through a cylinder head port. This paper investigates the shape of a cylinder head port effects on the flow of the port and the horsepower and the torque of the engine. Two port shapes were examined, the stock port shape which is round and a modified port shape which is approximately an upside down triangle. By using computational and experimental analysis a direct relationship is demonstrated between the shape of the port and the performance characteristics of the engine.

In this study three dimensional numerical simulations were carried out for steady incompressible flows around complex airfoil shapes. NACA-0012 and NACA-23012 wing with 20 percent-c Clark Y flap were used for this study. This work shows that the CutCell mesh method has the ability to generate high quality mesh which captures the details of the viscous boundary layer.

Understanding the disintegration mechanism, spray penetration, and spray motion is of great importance in the design of a high quality diesel engine. The atomization process that a liquid would undergo as it is injected into a high-temperature, high-pressure air, is investigated in this work. The purpose of this study is to gain further insight into the atomization mechanism, the variation over time in droplet size distribution and spray penetration. This is done based on effect of chamber pressure, injection pressure, and type of fuel. A laser diffraction method is used to determine droplet mean diameters, single injection with synchronized time mechanism allowed the time dependent studies. Obscuration signals are obtained through a digital oscilloscope from which arrival time of spray can be measured. The spray penetration correlation obtained is compared to other correlations obtained from different other techniques used in the literature.

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.

Investigations were conducted on how to improve vehicle performance by improving throttle response. A method for improving throttle response was to reduce the rotating and reciprocating mass in the engine. Two engines, which only differed in the amount of rotating and reciprocating mass, were investigated. Based on tests on a chassis dynamometer, it was observed that there was an 18% faster throttle response for the engine possessing the lower amount of rotating and reciprocating mass.