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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.

To stay competitive, new products require faster development time at low cost and good quality. Defense as well as commercial industries are forced to use analytical tools to stay competitive in a tough market. The use of simulation tools and approximation techniques in evaluating product performance during the early stages of the product development has a major impart on the product development efficiency, effectiveness, and lead time. Building physical prototypes of complex systems is expensive and it is difficult and time consuming to develop them. It is extremely beneficial to know as much as possible about the product performance and to optimize its dynamic characteristics before the first physical prototype is built.

The airflow through a standard automotive throttle body is not exactly proportional to the displacement of the accelerator pedal. Therefore, another method is needed to open the butterfly valve in order to ensure that airflow through the throttle body is metered equal to pedal displacement. This paper finds that the implementation of a cam-type pulley is necessary to achieve this prescribed goal.

A vehicle’s exterior fit and finish, in general, is the first system to attract customers. Automotive exterior engineers were motivated in the past few years to increase their focus on how to optimize the vehicle’s exterior panels split lines quality and how to minimize variation in fit and finish addressing customer and market required quality standards. The design engineering’s focus is to control the deviation from nominal build objective and minimize it. The fitting process follows an optimization model with the exterior panel’s location and orientation factors as independent variables. This research focuses on addressing the source of variation “contributed factors” that will impact the quality of the fit and finish. These critical factors could be resulted from the design process, product process, or an assembly process. An empirical analysis will be used to minimize the fit and finish deviation.

Cooling fans have many applications in industrial and electronic fields that remove heat away from the system. The process of designing a new cooling fan with optimal performance and reduced acoustic sources can be fairly lengthy and expensive. The use of CFD with support of mesh morphing, along with the development of optimization techniques, can improve the acoustic’s performance of the fan model. This paper presents a new promising method which will support the design process of a new cooling fan with improved performance and less acoustic surface power generation. The CFD analysis is focused on reducing the acoustic surface power of a given cooling fan’s blade using the surface dipole acoustic power as the objective function, which leads to an optimized prototype design for a better performance. The Mesh Morpher Optimizer (MMO) in ANSYS Fluent is used in combination with a Simplex model of the broadband acoustic modeling.

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.

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.

A study has been conducted on a small engine cooling system in order to find a way to reduce common overheating problems at idle conditions and high engine speeds with restricted airflow. The system flow rates, pressure, and temperature characteristics were monitored at different positions in the system while engine speed was varied. The results show that by adjusting the flow rates according to certain variables, the overall effectiveness of the system is increased and overheating problems can be eliminated. The findings also show that this adjustment can be accomplished by incorporating a controllable electric water pump into the design. Dynamometer testing has also been conducted to show that, in addition to controlling flow rates, the use of the electric pump also possesses the potential of increasing the power output of the engine.

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 paper examines the benefits of reducing the rotating mass in a Honda CBR600F4i engine to increase throttle response. Two engines, differing only in the amount of rotating and reciprocating mass, were built for testing. The engines were tested on a FSAE chase dynamometer to determine their individual throttle response, defined as the rate of increase of vehicle speed. As anticipated, the engine containing a lower amount of rotating and reciprocating mass produced a 21.5% faster throttle response.

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.

The Formula SAE (FSAE team for 2000) at Lawrence Technological University is utilizing parts and equipment from a four cylinder, four carburetor, 600cc four stroke Honda motorcycle engine. These parts will provide the crankshaft and camshaft position information to an Engine Control Module that will control the engine when fuel injection is used to replace the carburetors. The FSAE team will develop an improved method to determine the crankshaft and camshaft positions. The new method will be implemented by adding sensors and electronic circuit to perform the necessary calculation to obtain the crankshaft and camshaft position.

A cooling fan is an essential device of the engine cooling system which is used to remove the heat generated inside the engine from the system. An essential element for successful fan designs is to evaluate the pressure over the fan blade since it can generate annoying noices, which have a negative impact on the fan’s performance and on the environment. Reducing the acoustic surface power will assist in building improved designs that comply with standards and regulations in achieving a more quiet environment. The usage of computational fluid dynamics (CFD), with support of mesh morphing, can provide simulation study for optimizing the shape of a fan blade to reduce the aeroacoustic effects. The investigation process will assist in examining and analyzing the acoustic performance of the prototype, impact of different parameters, and make a solid judgement about the model performance for improvement and optimization.

The design of a race engine intake system involves many design considerations. Two very important areas of design are the intake manifold's volume and geometry. In considering these variables there are several different possible intake configurations. Such configurations will include single and dual plenum designs, as well as volume transitions. Dynamometer testing objectives will test different intake designs for the best overall engine power by comparing the areas under the engine power curve. Of the four intakes tested, the 2003 intake was found to make the best overall power.

The purpose of this paper is to develop the transfer function for the ride and handling performance for military tracked vehicle. This transfer function will be used in placed of the expensive physical hardware or simulation model for further study for robust design and optimization studies. Response Surface Methodology (RSM) approximation technique was used to develop the transfer functions. The RSM comprises of a group of statistical techniques for empirical model building and exploitation. RSM uses Design of Experiment (DOE) and multiple linear regression techniques for fitting of a response surface model that relates the output response to the design variables. The general form of the transfer function is a second order polynomial with unknown parameters to be identified. These unknown parameter were determined using the Central Composite Design (CCD) design of experiments.