Open Access. Powered by Scholars. Published by Universities.®

Aerospace Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Mechanical Engineering

2022

Institution
Keyword
Publication
Publication Type
File Type

Articles 121 - 127 of 127

Full-Text Articles in Aerospace Engineering

Regulation Of Dendrite-Free Li Plating Via Lithiophilic Sites On Lithium-Alloy Surface, Yufang He, Mengyun Zhang, Aiping Wang, Bo Zhang, Hiep Pham, Qiao Hu, Li Sheng, Hong Xu, Li Wang, Jonghyun Park, Xiangming He Jan 2022

Regulation Of Dendrite-Free Li Plating Via Lithiophilic Sites On Lithium-Alloy Surface, Yufang He, Mengyun Zhang, Aiping Wang, Bo Zhang, Hiep Pham, Qiao Hu, Li Sheng, Hong Xu, Li Wang, Jonghyun Park, Xiangming He

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Lithium (Li) deposition behavior plays an important role in dendrite formation and the subsequent performance of lithium metal batteries. This work reveals the impact of the lithiophilic sites of lithium-alloy on the Li plating process via the first-principles calculations. We find that the Li deposition mechanisms on the Li metal and Li22Sn5 surface are different due to the lithiophilic sites. We first propose that Li plating on the Li metal surface goes through the "adsorption-reduction-desorption-heterogeneous nucleation-cluster drop "process, while it undergoes the "adsorption-reduction-growth "process on the Li22Sn5 surface. The lower adsorption energy contributes to the easy adsorption of Li on …


Direct Numerical Simulation Of Acoustic Disturbances In A Hypersonic Two-Dimensional Nozzle Configuration, Nathaniel Hildebrand, Meelan M. Choudhari, Cole P. Deegan, Junji Huang, Lian Duan Jan 2022

Direct Numerical Simulation Of Acoustic Disturbances In A Hypersonic Two-Dimensional Nozzle Configuration, Nathaniel Hildebrand, Meelan M. Choudhari, Cole P. Deegan, Junji Huang, Lian Duan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Direct numerical simulations (DNS) are performed to study acoustic radiation in a quasi-two-dimensional nozzle with two independents spatially evolving turbulent boundary layers with an edge Mach number of 6. The emphasis of this work is to compare the radiated pressure fluctuations in a geometrically confined environment with those radiated from a single wall in an unconfined setting. The boundary-layer profile of the rms pressure fluctuation scaled by the mean shear stress at the wall is found to be in good agreement with prior flat-plate calculations at similar conditions. However, the normalized rms pressure fluctuation within the freestream p region is …


Nanobubble Capillary Force Between Parallel Plates, Eric Bird, Zhi Liang Jan 2022

Nanobubble Capillary Force Between Parallel Plates, Eric Bird, Zhi Liang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The Aggregation of Fine or Ultrafine Particles in Liquid Due to the Nanobubble (NB) Bridging Capillary Force is a Key Process for Many Industrial Applications. the Magnitude and Direction of the NB Capillary Force (NBCF) Are Directly Affected by the Geometry of the NB Gas Bridge between Two Adjoining Particles. Although the NBCF Can Be Accurately Measured using Experimental Techniques, It is Very Challenging to Monitor the Images of a NB Capillary Bridge in Nanoscale Spatial Resolution in NBCF Measuring Experiments. as a Result, the Capillary Force Model that Predicts the Dependence of the NBCF on the Geometry of the …


A Non-Reacting Passive Scalar Comparison Of Starccm And Openfoam In A Supersonic Cavity Flame Holder, Thomas Nuese Jan 2022

A Non-Reacting Passive Scalar Comparison Of Starccm And Openfoam In A Supersonic Cavity Flame Holder, Thomas Nuese

Electronic Theses and Dissertations

The scramjet engine equipped with a modern-day airliner would allow for very quick travel across the United States. The major problem is that designing such an engine and testing it to make sure it is safe would cost millions if not billions of dollars. Computational fluid dynamics allows for complex designs to be tested but can still take many days, weeks, or even months to complete. With the use of computational fluid dynamics (CFD), the scramjet engine can be analyzed to determine a quicker way to test and develop a reliable configuration in addition to analyzing the effects of different …


Investigations Of The Low Temperature Combustion Regions And Emissions Characteristics Of Aerospace F24 In A Constant Volume Combustion Chamber And A Common Rail Direct Injection Ci Engine, Richard C. Smith Iii Jan 2022

Investigations Of The Low Temperature Combustion Regions And Emissions Characteristics Of Aerospace F24 In A Constant Volume Combustion Chamber And A Common Rail Direct Injection Ci Engine, Richard C. Smith Iii

Electronic Theses and Dissertations

A study was conducted to investigate the low temperature combustion (LTC) regions of aerospace F24 and ULSD in the static setting of a CVCC and the dynamic setting of a CRDI research engine. This research is conducted to reduce in-cylinder emissions by understanding and implementing a technique to achieve an extended LTC. Emissions data for this study were collected during the operation of the CRDI research engine with a MKS 2030 FTIR and an AVL Microsoot 483. The parameters researched within the static setting of the CVCC included the determinations of the cool flames and NTC regions within the LTHR …


Development Of Predictive Ballistic Models For Hypervelocity Impact On Sandwich Panel Satellite Structures, Riley Carriere Jan 2022

Development Of Predictive Ballistic Models For Hypervelocity Impact On Sandwich Panel Satellite Structures, Riley Carriere

Electronic Theses and Dissertations

Sandwich panels are widely used in the design of uninhabited satellites and, in addition to having a structural function can often serve as shielding, protecting the satellites’ equipment from hypervelocity impacts (HVI) of orbital debris, and micrometeoroids. This thesis aims to provide: a comprehensive review of HVI experimental studies for honeycomb- and open-cell foam-cores; an examination of available predictive models used to assess the panels’ ballistic limits; as well as signify the influence of honeycomb-core parameters, such as cell size and foil thickness, as well as core material, on the ballistic performance of honeycomb-core sandwich panels (HCSP) when subject to …


Cfd And Heat Transfer Analysis Of Rocket Cooling Techniques On An Aerospike Nozzle, Geoffrey Sullivan Jan 2022

Cfd And Heat Transfer Analysis Of Rocket Cooling Techniques On An Aerospike Nozzle, Geoffrey Sullivan

Electronic Theses and Dissertations

In recent years the development of rocket engines has been mainly focused on improving the engine cycle and creating new fuels. Rocket nozzle design has not been changed since the late 1960s. Recent needs for reliable and reusable rockets, as well as advancements in additive manufacturing, have brought new interest into the aerospike nozzle concept. This nozzle is a type of altitude adjusting nozzle that is up to 90% more efficient than bell nozzles at low altitudes and spends up to 30% less fuel. Since the nozzle body is submerged in the hot exhaust gasses it is difficult to keep …