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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).

Enhancing the performance of centrifugal pumps requires a thorough understanding of the internal flow. Flow simulation inside the pump can help understand the rotatory motion induced by the impellers, as well as the flow instabilities. The flow inside a centrifugal pump is three dimensional, disturbed and accompanied by tributary flow structures. When a centrifugal pump operates under low flow rates, a secondary flow known as recirculation starts to begin. The separation of flow occurs which creates vortices and decreases local pressure which induces cavitation. This phenomenon of recirculation will rise the Net Positive Suction Head Required (NPSHR). This work aims to improve the pump efficiency under low flow rates by adding multiple cylindrical disks at the pump inlet section to suppress the flow recirculation. In this study, a numerical simulation is carried out to investigate the influence on the pump internal flow by adding multi cylindrical disks.

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.

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.

A description is provided detailing the results of the quality function deployment process used to identify customer needs and requirements. Through this process two primary project goals were developed consisting of integrating an electrical-solenoid actuated device into existing space constraints and providing cost reduction alternatives. A static and dynamic analysis was initially required to find the boundary conditions of the external forces imposed on the existing pneumatic device while being subjected to multiple pallets impacting the stop block assembly. Further static analysis was conducted to find the internal forces imposed on the stop arm subassembly in order to properly size the electrical solenoid. Subsequent research into various solenoids led to two solenoid manufacturers evaluated by means of a design evaluation matrix.

Chromium Molybdenum Steel (AISI 4130), commonly referred to as “Chrome Moly”, is one of the most popular materials used in the construction of tubular space frames and chassis components for racing applications. Its high strength, light weight and comparably low material cost make the reasons for its popularity quite obvious. However, there is one problem that is commonly overlooked: maintaining the strength component of Chrome Moly in areas exposed to high levels of heat followed by rapid cooling during welding. This paper seeks to better understand the affects of cooling due to welding on the strength of Chrome Moly tubing.

Controlling the Cost of Variance is essential to the manufacturing process of Printed Circuit Board Assembly for low volume high mix production. The material variance is identified as the additional components and resources consumed beyond the minimum required to complete the project. This Quantity Variance occurs at the effects of defects at key steps of the manufacturing process. Such occurrences result in the need to purchase additional components for the completion of the order. These additional components termed Quantity Variance alter the sequence of the manufacturing process affecting quality, timely delivery of the job and directly impacting company profitability.

A study was performed to determine the effects of varying the wall thickness and material glass fiber concentration for parallel and perpendicular shrinkage rates for a constrained thin-walled box shaped component. An analysis of the shrinkage for the bottom portion of a 3 dimensional constrained thin walled injection molded component was performed using measurements made from bitmap images of the components that were obtained from a traditional flatbed scanner. The shrinkage rates were determined by comparing mold cavity hatch lines to the correlating transposed hatch lines on the plastic molded component. The perpendicular and parallel shrinkage rates were determined and are discussed as a function of thickness and glass fiber content. A wide range of processing control factors was used in the study.

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.

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.

This paper discusses the design and application of a semi-active damping system controlled by a student designed microprocessor that reads accelerations laterally and longitudinally from separate accelerometers to anticipate chassis orientation and responds with an analog voltage to each damper. This dynamically alters the shock oils effective viscosity to keep the chassis movement within desired parameters. The system described will be incorporated into a one-seater open wheeled racecar that is outfitted with a non-parallel, unequal length SLA suspension designed for entry in the 2001 Formula SAE competition. The focus will be more on the damping of low and high frequency obstacles and the resulting chassis (sprung mass) control rather than controller design, since it is an entirely different collection of papers unto itself.

The primary function of the electrical system for the Lawrence Tech Formula SAE 2001 vehicle was to supply essential engine and vehicle functions. Important secondary functions of the electrical system were real-time data acquisition, display of some of these data to the driver, and transmission of the data to race team members at a sideline location. In addition to data channels depicting vehicle function and health, the data-acquisition (DAC) system included video that duplicated the driver's view, and two-way audio. This paper describes the DAC system and its integration into the vehicle electrical system.

This paper discusses how to effectively design and set-up an ideal spring/damper combination in a low-mass open wheeled racecar to properly control vehicle handling and gain optimum performance of the system. The system that will be discussed is outfitted with a non-parallel, unequal length SLA suspension that was designed and raced at the 2001 Formula SAE competition. The focus of this paper will be more on how to choose an ideal suspension set-up for a low-mass open wheeled racecar, while considering the various variables that can affect the system as a whole. To properly design a suspension, a passive system will be used, and then the performance gains of a semi-active system will be introduced and discussed.

The 2002 Lawrence Technological University Formula SAE team set out to develop a tuned exhaust system for a restricted Honda CBR 600 F4i engine. The exhaust system was targeted for maximizing low rpm torque while maintaining a broad flat torque curve without a significant loss of high rpm horsepower. In order to do this, considerable attention had to be given to the exhaust primary tracts, collector and silencer designs. To test theory, two equal length, fully adjustable headers were manufactured and tested on an engine dynamometer. Experimentally, the optimal exhaust design to meet our vehicles needs was determined.

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.

The objective of this research is to develop a component based enhanced production process after End of Line (EOL) testing. This process will add more quality validation evaluations, but will not require any disassembling of the parts or damage to them. It will help the suppliers to avoid scrap and rework parts as well as General Motors (GM) to reduce warranty and recalls. An Enhanced Production Process was implemented in March, 2016 at a supplier in Mexico. The Enhanced Audit Station implementation is to ensure that the supplier is satisfying the Production Part Approval Process (PPAP) requirements. The most important four components are: Touch Appearance Lighting and Color (TALC), Appearance Approval Report (AAR), Dimensional Checks, and Function Testing. Through statistics, a pilot study was conducted to correlate the selected variables to reduce warranty.

This paper presents an experimental investigation of flow field instabilities in a centrifugal pump impeller at low flow rates. The measurements of pump hydraulic performance and flow field in the impeller passages were made with a hydraulic test rig. Analysis of Q-ΔP-η data and flow structures in the impeller passages were performed. In the present work, the effect of various flowrates on centrifugal pump impeller performance was analyzed based on pump measured parameters. The impeller’s geometry was modified, with positioning the curved spacer at the impeller suction side. This research investigates the effect of each inlet curved spacer model on pump performance improvement. The hydraulic performance and cavitation performance of the pump have been tested experimentally. The flow field inside a centrifugal pump is known to be fully turbulent, three dimensional and unsteady with recirculation flows and separation at its inlet and exit.

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.