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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.

A unique differential assembly was needed for the Lawrence Technological University (LTU) SAE Formula race car. Specifically, a differential was required that had torque sensing capabilities, perfect reliability, high strength, light weight, the ability to withstand inertia and shock loading, a small package, no leaks, the ability to support numerous components. In that regard, an existing differential was selected that had the torque sensing capabilities, but had deficiencies that needed to be fixed. Those deficiencies included the following: Differential unit was over 4 kg unmounted, with no housing. This was considered too heavy, when housed properly. Bearing surface was provided on only one end of the carrier. This design provides insufficient bearing surface to support either the differential housing or half-shafts The internal drive splines integral to the case are not optimized for a perpendicular drive/axle arrangement, such as, a chain drive.

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.

A new inter-disciplinary degree program has been developed at Lawrence Technological University: the Master of Science in Mechatronic Systems Engineering Degree (MS/MSE). It is one of a few MS-programs in mechatronics in the U.S.A. today. This inter-disciplinary program reflects the main areas of ground vehicle mechatronic systems and robotics. This paper presents areas of scientific and technological principles which the Mechanical Engineering, Electrical and Computer Engineering, and Math and Computer Science Departments bring to Mechatronic Systems Engineering and the new degree program. New foundations that make the basis for the program are discussed. One of the biggest challenges was developing foundations for mechanical engineering in mechatronic systems design and teaching them to engineers who have different professional backgrounds. The authors first developed new approaches and principles to designing mechanical subsystems as components of mechatronic systems.

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.

All-wheel drive (AWD) vehicle performance considerably depends not only on total power amount needed for the vehicle motion in the given road/off-road conditions but also on the total power distribution among the drive wheels. In turn, this distribution is largely determined by the driveline system and its mechanisms installed in power dividing units. They are interwheel, interaxle reduction gears, and transfer cases. The paper presents analytical methods to evaluate the energy and, accordingly, fuel efficiency of vehicles with any arbitrary number of the drive wheels. The methods are based on vehicle power balance equations analysis and give formulas that functionally link the wheel circumferential forces with slip coefficients and other forces acting onto an AWD vehicle. The proposed methods take into consideration operational modes of vehicles that are tractive mode, load transportation, or a combination of both.

The 2000 Formula SAE Team at Lawrence Technological University (LTU) has designed a chain driven, three-piece aluminum differential unique from past years. This innovative design introduces an adjustable chain mount replacing conventional shackles. Made completely of aluminum, this device moves the entire rear drive train. The gear set remains to be limited slip with a student designed housing. The idea of an aluminum housing with manufactured gear set is a continued project at LTU. After cutting approximately 33% from the weight of the 1999 differential, the 2000 is geared toward a simpler, and smaller design, easier assembly and lighter weight. After reading this brief overview, the idea of this paper is to provide an understanding of the reasoning behind the choices made on the LTU driveline team. FIGURE 1

To obtain a maximum range for usable torque, Helmholtz theory is utilized to tune an Honda CBR 600 cc engine. The design objectives were to: 1) Increase performance by reducing pressure losses in the entire intake system; 2) Maximize the restrictor's design to increase airflow at lower pressure drops; 3) Improve throttle response through throttle body design and reduction of turbulence when full open; 4) Utilize runner design to improve tuning effects as predicted by Helmholtz resonance theory and; 5) Incorporate a plenum design with equal air distribution to all four cylinders.

Aerodynamics plays an important role in the dynamic behavior of a vehicle. The purpose of this paper is to evaluate external and internal aerodynamics of the 1999 and 2000 Lawrence Technological University Formula SAE vehicles. The external aerodynamic study will be limited to form and interference drag and the evaluation of lift. The internal aerodynamics study will be limited to ram air to the intake, heat exchanger, and oil cooler.

A low cost fault tolerant and redundant multiplex wiring system specifically designed for automotive applications is described in this paper. Although there are many multiplex wiring systems are being used to simplify the car wiring harness, but very few are low cost, fault tolerant and redundant at the same time. Most of the system address mainly the protocol and software issues and neglected the reliability of the multiplex wiring system. This paper addresses the fault tolerant and redundancy of the system and use hardware based integrated circuit to convert from parallel to serial at the transmitter side and serial to parallel at the receiver side.

Aerodynamic drag is the force that restricts the forward velocity of a vehicle. Sources of drag are form drag, interference drag, internal flow drag, surface friction, and induced drag. Aerodynamic drag directly impacts the fuel economy attainable by a vehicle. In the Formula SAE competition (FSAE), fuel economy is a factor during the endurance phase. This paper will focus on the effects of aerodynamic drag and how it impacts the fuel economy of a FSAE racing style vehicle. Using the Lawrence Technological University (LTU) 1999 and 2000 cars to study and evaluate various methods to reduce drag and optimize fuel economy. Theoretical and experimental methods will be used and the study will be limited to the effects of form and interference drag.

This paper is an introduction to the design of suspension components for a Formula SAE car. Formula SAE is a student competition where college students conceive, design, fabricate, and compete with a small formula-style open wheel racing car. The suspension components covered in this paper include control arms, uprights, spindles, hubs, pullrods, and rockers. Key parameters in the design of these suspension components are safety, durability and weight. The 2001 Lawrence Technological University Formula SAE car will be used as an example throughout this paper.

A new induction system has been developed, created, and tested for use in the 2001 Formula SAE competition. A 600 Honda CBR F4 four-stroke engine intake is designed using dual plenums, which prevents charging losses due to overlapping intake events at low engine speeds. Dual butterfly valves actuated at high engine speeds enable plenum volume combination for improved high-end performance. The intake restrictor venturi design has also been improved.

As proven, both friction in the gearing and movement of the contact point of the teeth in mesh along the pressure line generate vibrations of the axial components of the resultant force acting in a couple of mating straight bevel gears. The vibrations of the real forces in gearings cause an increased dynamic pressure on and, accordingly, damage of frictional surfaces of differential parts. The law of summing up the axial components of all the gearings in two and four pinion differentials depends on combinations of numbers of the side gear's and pinion's teeth. A classification of bevel gear differentials into four groups depending on those combinations has been carried out. Differentials of the four groups have different degrees of the axial force vibration. The paper presents a detailed method to evaluate theoretically the axial forces in each of the groups. As shown, differentials from one of the four groups (Group III) have decreased axial force vibrations.

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.

There is evidence to suggest that before military equipment ever experiences sustainment delays the equipment carries state patterns within its logistics and supply chain data history that could be leveraged for risk mitigation. Analysis of these patterns can also identify new research & development (R&D) and technology transition candidates that relate the seemingly disparate activities of R&D project management and Diminishing Manufacturing Sources and Material Shortages (DMSMS) management. Relating eligible R&D activities to the DMSMS risk identification phase helps stage potential sustainment risk mitigations ahead of time on the one hand, while creating additional demand and resources to mature prototypes on the other hand.

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 paper, a reconfigurable object-oriented simulator is proposed to analyze the performance of Bluetooth Voice Communication Package (VCP) for telecom purposes like hands-free vehicular communication. It consists of a graphical user interface (GUI) for research or validation engineers to investigate system specific performance. For example, a research engineer can utilize this GUI to analyze a system performance using different noise reduction filtering techniques in vehicular hands-free applications. Also, a validation engineer can utilize this GUI to evaluate vehicular Bluetooth audio quality for different vehicles at different driving conditions (e.g. speeds, fan levels, etc.). The proposed Bluetooth VCP model consists of modules like Audio Equalization (EQ), Acoustic Echo Canceller (AEC), and Noise Suppression (NS). This dynamic GUI platform provides the scope to add and analyze new proposed filtering techniques.

The experimental methods focused on utilizing the newly developed NOVA induction heating and hardening manufacturing process as an adapted method to produce high performance engine valve springs. A detailed testing plan was used to evaluate the expected and theorized possibility for fatigue life enhancement. An industry standard statistical analysis method and tools were employed to objectively substantiate the findings. Fatigue cycle testing using NOVA induction-hardened racing valve springs made of ultra-high tensile material were compared to data for springs with traditional heat treatment and those with standard processing. The results were displayed using Wöhler and modified Haigh fatigue life diagrams. The final analysis suggests that NOVA processed springs have a seemingly slight, yet significant benefit in fatigue life of 5 - 7% over springs processed through a competing method.