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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.

Manual transmissions for passenger cars are facing pressures due to rapid growth of automatic transmissions, which already represents more than 60% of Brazil market, and from higher torque demand due to strict emission legislation, which turbo engines had presented great contribution to it. To solve this contradictory issue, gears with higher strength and lower cost have been studied to replacement Nickel by Niobium in the steels. Furthermore, this technology could be applied to solve the issues with electrified vehicle, where high torque, speed and lifetime are demanded pursued for gears. This study aimed to build prototypes and compare the S-N curves, fracture analysis, microstructure for three kinds of steels (QS4321 with Ni, QS1916 FG without Ni & with Nb and QS 1916 without Ni and Nb) in the condition carburized, hardened and tempered with and without shot peening.

Cold spray (CS) is a rapidly developing solid-state repair and coating process, wherein metal deposition is produced without significant heating or melting of metal powder. Solid state bonding of powder particles is produced by impact of high-velocity powder particles on a substrate. In CS process, metal powder particles typically of Aluminum or Copper are suspended in light weight carrier gas medium. Here high pressure and high temperature carrier gas is expanded through a converging-diverging nozzle to generate supersonic gas velocity at nozzle exit. The CS process typically uses Helium as the carrier gas due to its low molecular weight, but Helium gas is quite expensive. This warrants a need to explore alternate carrier gases to make the CS repair process more economical. Researchers are exploring another viable option of using pure Nitrogen as a carrier gas due to its significant cost benefits over Helium.

The commercial vehicle industry continues to move in the direction of improving brake thermal efficiency while meeting more stringent diesel engine emission requirements. This study focused on demonstrating future emissions by using an exhaust burner upstream of a conventional aftertreatment system. This work highlights system results over the low load cycle (LLC) and many other pertinent cycles (Beverage Cycle, and Stay Hot Cycle, New York Bus Cycle). These efforts complement previous works showing system performance over the Heavy-Duty FTP and World Harmonized Transient Cycle (WHTC). The exhaust burner is used to raise and maintain the Selective Catalytic Reduction (SCR) catalyst at its optimal temperature over these cycles for efficient NOX reduction. This work showed that tailpipe NOX is significantly improved over these cycles with the exhaust burner.

Electrification is one of the megatrends across the industries, like electric vehicles, electric aircraft, etc. which needs advancement in power electronics component technology. As technology advances in miniaturization of power electronics, thermal-management issues threaten to limit the performance of these devices. These may force designers to derate the device performance and ultimately these compromise in design may increase the size & weight of the application. One of the technologies capable of accomplishing these goals employs a class of materials know as metal foam. Metal foams are lightweight cellular materials inspired by nature. The main application of metal foams can be grouped into structural and functional and are based on several excellent properties of the material. Structural applications take advantage of the light-weight and specific mechanical properties of metal foam.

Commercial vehicles are moving in the direction of improving brake thermal efficiency while also meeting future diesel emission requirements. This study is focused on improving efficiency by replacing the variable geometry turbine (VGT) turbocharger with a high-efficiency fixed geometry turbocharger. Engine-out (EO) NOX emissions are maintained by providing the required amount of exhaust gas recirculation (EGR) using a 48 V motor driven EGR pump downstream of the EGR cooler. This engine is also equipped with cylinder deactivation (CDA) hardware such that the engine can be optimized at low load operation using the combination of the high-efficiency turbocharger, EGR pump and CDA. The exhaust aftertreatment system has been shown to meet 2027 emissions using the baseline engine hardware as it includes a close coupled light-off SCR followed by a downstream SCR system.

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.

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%.

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%.

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 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.

In the present work, the effect of various nanofluids on automotive engine cooling was experimentally studied. Al2O3, TiC, SiC, MWNT (multi-walled nanotube), and SiO2 nanoparticles with average diameter ranging between 1 and 100 nm were mixed with distilled water to form nanofluids. An ultrasonic generator was used to generate uniform particle dispersion in the fluid. A compatibility test was carried out on all nanofluids and it was found that TiC, MWNT, and Si3N4 nanoparticles settled and separated from the fluid within 3 hours after preparation. The engine cooling performance testing setup consisted of an Aprilia SXV 450 engine, the nanofluid cooling loop, a radiator, a fan, etc. Thermocouples and resistance temperature detectors (RTD’s) were attached to the inlet and outlet of the radiator hose to monitor the temperature changes taking place in the cooling system. A flowmeter was attached to the inlet hose of the radiator to monitor the coolant flow rate.

Emission, fuel economy and productivity in non-road mobile machinery (NRMM) depend largely on drive cycles. Understanding drive cycles can provide the in-depth information and knowledge that help the system integrator better optimize the vehicle management system. Some non-road engine test cycles already exist nowadays. However, these cycles are mainly for engine emission regulation purpose, and not closely tied to real world applications. Therefore, from both industries and academia, it has been the common practice to instrument and retrofit a vehicle, assign a professional driver operate the retrofitted vehicle for real testing, and compare the results to the baseline vehicle under the similar operating conditions. Obviously this approach is time consuming and resource intensive. In this paper, we attempt to address this issue by introducing a method of constructing standard drive cycles from in-field operation data.