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Recently, there has been a new method for setting bearing preload on tapered roller bearings in a power transmission system. To move this new method into production, an analytical model that relates the bearing preload to the stiffness of the bearing was developed. This work develops an analytical model that links the preload on multi-row tapered roller bearings to the stiffness of the power transmission system. This study also validates the proposed analytical model by comparing it to both previous work and commercially available simulation software. The analytical model has shown that it is highly sensitive to the number of rollers in the bearing, which is discussed in this work.

Online road profiling capability is required for automotive active suspension systems to be realized in a commercial landscape. The challenges that impede the realization of these systems include a profiler’s ability to maintain an optimal resolution of the oncoming road profile (spatial frequency). Shifting of the profile measurement frame of reference due to body motion disturbances experienced by the vehicle also negatively impacts profiling capability. This work details the early development of a corrective look-ahead road profiling system (CLARPS) and its control logic. The CLARPS components are introduced and additional focus will be given to the development of the angle generating function (AGF) and how it drives the ability of the system to optimize look-ahead viewing angles for the best spatial frequency resolution of a road profile. The CLARPS simulation environment is demonstrated with numerical comparison of simulated road profiles at varying vehicle speeds.

A vehicle-level data acquisition (DAQ) system was developed and implemented on the Lawrence Technological University (LTU) Baja SAE vehicle. This low-cost Arduino-based DAQ system is capable of accurately and repeatedly measuring Baja SAE specific vehicle parameters and storing them for offline analysis. While expandable for the needs of future teams, the developed DAQ system includes measurement of vehicle wheel speed, CVT pulley speeds, suspension position, CVT belt temperature, steering load, and steering angle. The development of the DAQ system architecture and the development of the angular speed and suspension position measurement subsystems are the focus of this work. The processes followed and lessons learned can be used by other Baja SAE and SAE Collegiate Design Series. Each measurement subsystem was designed, fabricated, integrated, and validated on the bench and in-vehicle.

Designing a centrifugal pump impeller comes with challenges due to multiple parameters that affect the pump efficiency. A high velocity gradient exists in the flow between the impeller shroud and sidewall of the pump casing due to one surface stationary and the other moving at a high velocity. The internal rotating flow in the impeller shroud-sidewall gap is a major problem that leads to a decrease in pump performance. This study presents a design modification of the gap between the impeller shroud and the pump casing sidewall using an idler disk located in between, which rotates freely during pump operation. In this paper, a numerical analysis was performed to investigate the idler disk's effect on the pump performance for different volumetric flow rate values and idler disk geometries. ANSYS-2019-R1 was used (FLUENT solver) to carry out the computational fluid dynamics (CFD) analysis for evaluating the performance of the baseline and modified designs in a centrifugal pump.

The objective of this study is to develop a robust framework to model shock-turbulence interactions that happen in many engineering applications dealing with compressible flows. The model is essentially a hybrid algorithm to address the conflict between turbulence modeling and shock-capturing requirements. A skew-symmetric form of a co-located finite volume scheme with minimum aliasing errors is implemented to model the turbulent region in the combination of a semi-discrete, central scheme to capture the discontinuities with sufficiently low dissipation to minimize the effect of large eddy simulation (LES) for turbulent flows. To evaluate the effectiveness of the model, LESs are conducted to study the interaction of stationary shocks with turbulent flows. The simulations of the shock-turbulence interaction show the same physical trends as previously published results for high-fidelity DNS and LES.

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.

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.

Formula SAE Collegiate Competition teams now regularly integrate aerodynamic body kits with their vehicles which have significant benefits in producing downforce. This use of body kits (or aero packages) and the improvement to vehicle aerodynamics they provide, have resulted in these systems becoming a necessity for any team wishing to remain competitive in Formula SAE (FSAE). To address this the Lawrence Technological University (LTU) Formula SAE team incorporated an aerodynamic body kit into their 2018 vehicle. Using computational fluid dynamics (CFD) an aerodynamic analysis was performed comparing the efficacy of a car that did not have an aero package to a car that did. Two separate simulation programs were employed to effectively and accurately assess this change. By using both SolidWorks and SimScale software to generate data, the results of each were compared to assess the accuracy of each.

Mechanical engineering students at Lawrence Technological University complete a five-credit hour capstone project: either an SAE collegiate design series (CDS) vehicle or an industry-sponsored project (ISP). Students who select the SAE CDS option enroll in a three-semester, three-course sequence. Each team of seniors designs, builds, and competes with their vehicle at one of the SAE CDS events. Three years after implementing major changes to the course structure and content, the three-semester capstone design sequence is revisited. Finalized learning objectives are presented and the sequence is assessed with a mix of direct, indirect, and anecdotal assessment. Student performance, as measured directly with design reports, milestones, and project completion, is good. Of the five Lawrence Tech CDS teams, only one has failed to be ready for competition since the changes were implemented.

Recently, composite materials/structures are getting increasingly used in the automotive and aerospace industry. Defects issue is commonly associated with the use of composite materials/structures. Reliable Non-Destructive Evaluation (NDE) of composite structures is still challenging due to the existence of small size defects. In this research, a hybrid approach is used to accurately determine small size internal defects. In this hybrid approach, X-Ray Computed Tomography is used as a reference to accurately determine all defect locations, then a digital shearography method is used to conduct fast NDE for in-line testing. The critical shearographic NDE parameters such as shearing angle, shearing distance and loading amount are determined and optimized based on the X-ray CT scan result. From the comparison of X-ray CT scan results and digital shearography NDE results, the detection rate of digital shearography for defects with a size of larger than 1mm is from 91.91% to 97.30%.

The behavior of different layer designs of a transparent armor (TA) under large strains been investigated. Impacts of light-armor piercing projectile (7.62x51AP) as influencers were tested and analyzed for predicting the TA response when the layers design angles are adjusted. The experimentation allows visualization of damage behavior and the projectile penetration. The visualization techniques are essential models for understanding the mechanisms of interaction between projectile and targeted material design. Ballistic tests results, high-speed photographs and flash-radiographs from experiments with transparent armor were used to establish LS-DYNA simulation module. Transient non-linear dynamic finite-element has been analyzed using LS-DYNA to simulate and validate the experimentation. The penetrative capability of the projectile was assessed in terms of both the ballistic limit velocity against various layer design angles of the TA and air gaps.

This paper presents methods of rapid prototyping design and manufacturing used in the development of a centrifugal pump impeller with curved spacer (CS). In this research subtractive and additive rapid manufacturing methods were applied to create complex curved spacer profiles for testing as part of geometry optimization process for a high speed and high flow rate centrifugal pump impeller. Seven models for the curved spacer were designed and each model was integrated with the bare impeller separately for simulation analysis. One design was selected for manufacturing with applying subtractive and additive processes. In subtractive manufacturing method, the raw material was removed from a solid shaft by a cutting process under digital control from a computer file. The complexity of the modified impeller spacer profiles required the use of expensive CNC machining with five axis capability.

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.

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.

AASHTO I-Beam is a standard structural concrete part for bridge sections. The flexural performance of an AASHTO I-Beam is critical for bridge design. This paper presents an application of Digital Image Correlation (DIC) Method in full-scale AASHTO I-Beam flexural performance study. A full-scale AASHTO I-Beam pre-stressed with steel strands is tested by three-point bending method. The full-scale AASHTO I-Beam is first loaded from 0 kips to 100 kips and is then released from 100 kips to 0 kips. A dual-camera 3D Digital Image Correlation (DIC) system is used to measure the deflection and strain distribution during the testing. From the DIC results, the micro-crack generation progress during the loading progress can be observed clearly from the measured DIC strain map. To enable such a large-scale DIC measurement, the used DIC setup is optimized in terms of the optical imaging system and speckle pattern size.

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%.

The initiative of this paper is focused on improving the heat dissipation from the pressure wheel of a laser welding assembly in order to achieve a longer period of use. The work examines the effects of different geometrical designs on the thermal performance of pressure wheel assembly during a period of cooling time. Three disc designs were manufactured for testing: Design 1 – a plain wheel, Design 2 – a pierced wheel, and Design 3 – a wheel with ventilating vanes. All of the wheels were made of carbon steel. The transient thermal reaction were compared. The experimental results indicate that the ventilated wheel cools down faster with the convection in the ventilated channels, while the solid plain wheel continues to possess higher temperatures. A comparison among the three different designs indicates that the Design 3 has the best cooling performance.

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.

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.