Mechanical Engineering Commons^™

Numerical Simulation Of Laser Induced Elastic Waves In Response To Short And Ultrashort Laser Pulses., Alireza Zarei

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In an era of intensified market competition, the demand for cost-effective, high-quality, high-performance, and reliable products continues to rise. Meeting this demand necessitates the mass production of premium products through the integration of cutting-edge technologies and advanced materials while ensuring their integrity and safety. In this context, Nondestructive Testing (NDT) techniques emerge as indispensable tools for guaranteeing the integrity, reliability, and safety of products across diverse industries.

Various NDT techniques, including ultrasonic testing, computed tomography, thermography, and acoustic emissions, have long served as cornerstones for inspecting materials and structures. Among these, ultrasonic testing stands out as the most prevalent method, …

Experimental Study On The Impact Of Low Thermal Inertia Thermal Barrier Coatings On Ppci-Diffusion Gci Combustion, Kunal Vedpathak

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The application of thermal barrier coatings (TBCs) has been studied in homogenous charge compression ignition (HCCI), conventional diesel combustion (CDC), and spark ignition (SI). Gasoline compression ignition (GCI) combines the low soot and NOx emissions of HCCI with combustion controllability through fuel stratification. GCI has become an interesting prospect due to the reduction in gasoline consumption due to the electrification and hybridization of the light-duty sector. It can be used as a preferred combustion mode in heavy-duty engines to reduce emissions with minimal modifications. GCI exhibits better combustion efficiency than HCCI. Advances in material technology have combined low thermal conductivity …

Applications Of Large Eddy Simulations To Novel Internal Combustion Concepts, Patrick O'Donnell

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Computational fluid dynamics (CFD) simulations of internal combustion engines (ICEs) are becoming an increasingly popular tool in the automotive industry to either explain experimentally observed trends or perform lower cost design iterations. The convenience of commercially available CFD software and advancements made in computing hardware have been the impetus behind this growing popularity. However, obtaining accurate results using these software packages is not a trivial process and requires an in-depth understanding of the underlying numerical methodology and sub models for various physical phenomena. Specific to the ICEs, CFD simulation often entails the use of models for detailed chemistry and combustion, …

Classification Of Electrical Current Used In Electroplastic Forming, Tyler Grimm

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Electrically assisted manufacturing (EAM) is the direct application of an electric current to a workpiece during manufacturing. This advanced manufacturing process has been shown to produce anomalous effects which extend beyond the current state of modeling of thermal influences. These purported non-thermal effects have collectively been termed electroplastic effects (EPEs).

While there is a distinct difference in results between steady-state (ideal DC) testing and pulsed current testing, the very definition of these two EAM methods has not been well established. A "long" pulse may be considered DC current; a "short" pulse may produce electroplastic effects; and even "steady-state" current shapes …

Multiple Heat Exchanger Cooling System For Automotive Applications – Design, Mathematical Modeling, And Experimental Observations, Zaker Syed

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The design of the automotive cooling systems has slowly evolved from engine-driven mechanical to computer-controlled electro-mechanical components. With the addition of computer-controlled variable speed actuators, cooling system architectures have been updated to maximize performance and efficiency. By switching from one large radiator to multiple smaller radiators with individual flow control valves, the heat rejection requirements may be precisely adjusted. The combination of computer regulated thermal management system should reduce power consumption while satisfying temperature control objectives. This research focuses on developing and analyzing a multi-radiator system architecture for implementation in ground transportation applications. The premise is to use a single …

Direct Numerical Simulation Of Supercritical Co2 Mixing And Combustion, Syed Mohammad Ovais

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The supercritical CO₂ power cycle (sCO₂ ) is a relatively new technology, which promises to reduce CO₂ emissions with potentially higher efficiencies. However due to challenging conditions posed by supercritical pressures, the mixing and ignition phenomena in sCO₂ combustion is relatively less understood and studied. The primary objective of the current study is to investigate these fundamental processes using homogeneous ignition calculations (HMI) and direct numerical simulations (DNS). Broadly, the study is divided into two major parts. In the first part supercritical mixing in sCO₂ relevant conditions is investigated. To achieve this, DNS of temporally …