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Articles 691 - 720 of 1144
Full-Text Articles in Mechanical Engineering
Thermal Conductivity Of Interfacial Layers In Nanofluids, Zhi Liang, Hai-Lung Tsai
Thermal Conductivity Of Interfacial Layers In Nanofluids, Zhi Liang, Hai-Lung Tsai
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Thermal Conductivity of Interfacial Layers is an Essential Parameter for Determining How the Ordered Liquid Layering Around the Particle-Liquid Interface Contributes to the Unusual High Thermal Conductivity of Nanofluids. However, So Far There is No Experimental Data Regarding This Parameter. using Nonequilibrium Molecular Dynamics Simulations of an Inhomogeneous Au-Ar System in Which the Solid-Liquid Interactions Are Assumed to Be Much Stronger Than the Liquid-Liquid Interactions, We Show Explicitly that the Thermal Conductivity of a 1-Nm-Thick Interfacial Layer is 1.6∼2.5 Times Higher Than that of the Base Fluid. the Simulation Results Are Incorporated into a Three-Level Clustering Model to Calculate the …
Fuel Cycle Co2-E Targets Of Renewable Hydrogen As A Realistic Transportation Fuel In Australia, Alberto Boretti
Fuel Cycle Co2-E Targets Of Renewable Hydrogen As A Realistic Transportation Fuel In Australia, Alberto Boretti
Mechanical and Aerospace Engineering Faculty Research & Creative Works
The claim of catastrophic manmade climate change or global warming through anthropogenic CO2 has presently focused the interest on the tailpipe emissions of CO2 per km, with recent legislations obsessively targeting these emissions of CO2 with defectively implemented procedures. with a variety of different propulsion solutions (electric, hybrid electric, hybrid mechanic, conventional) and different fuels (Diesel, Petrol, alternative fossil, alternative renewable) available in the near future, a more comprehensive approach based on the full fuel cycle, and eventually also the full life cycle of the vehicle appear to be necessary. the paper is a contribution to trigger …
Deterministic Integrated Tuning Of Multicavity Resonances And Phase For Slow-Light In Coupled Photonic Crystal Cavities, T. Gu, S. Kocaman, Xiaodong Yang, J. F. Mcmillan, M. B. Yu, G.-Q. Lo, D.-L. Kwong, C. W. Wong
Deterministic Integrated Tuning Of Multicavity Resonances And Phase For Slow-Light In Coupled Photonic Crystal Cavities, T. Gu, S. Kocaman, Xiaodong Yang, J. F. Mcmillan, M. B. Yu, G.-Q. Lo, D.-L. Kwong, C. W. Wong
Mechanical and Aerospace Engineering Faculty Research & Creative Works
We present the integrated chip-scale tuning of multiple photonic crystal cavities. The optimized implementation allows effective and precise tuning of multiple cavity resonances (up to ~1.60 nm/mW) and intercavity phase (~0.038 π/mW) by direct local temperature tuning on suspended silicon nanomembranes. Through designing the serpentine metal electrodes and careful electron-beam alignment to avoid cavity mode overlap, the coupled photonic crystal L3 cavities preserve their high quality factors. The deterministic resonance and phase control enables switching between the all-optical analog of electromagnetically-induced-transparency to flat-top filter lineshapes, with future applications of trapping photons and optoelectronic modulators.
Study Of Emission Turbulence-Radiation Interaction In Hypersonic Boundary Layers, L. (Lian) Duan, M. P. Martín, I. Sohn, D. A. Levin, M. F. Modest
Study Of Emission Turbulence-Radiation Interaction In Hypersonic Boundary Layers, L. (Lian) Duan, M. P. Martín, I. Sohn, D. A. Levin, M. F. Modest
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Direct numerical simulations are conducted to study the effects of emission turbulence-radiation interaction in hypersonic turbulent boundary layers, representative of the Orion Crew Exploration Vehicle at peak-heating condition during reentry. A nondimensional governing parameter to measure the significance of emission turbulence-radiation interaction is proposed, and the direct numerical simulation fields with and without emission coupling are used to assess emission turbulence-radiation interaction. Both the uncoupled and coupled results show that there is no sizable interaction between turbulence and emission at the hypersonic environment under investigation. An explanation of why the intensity of emission turbulence-radiation interaction in the hypersonic boundary layer …
On The Advantages Of E100 Over Gasoline In Down-Sized, Turbo-Charged, Direct-Injected, Variable Valve Actuated, And Stoichiometric S.I. Engines, Alberto A. Boretti
On The Advantages Of E100 Over Gasoline In Down-Sized, Turbo-Charged, Direct-Injected, Variable Valve Actuated, And Stoichiometric S.I. Engines, Alberto A. Boretti
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Current flexi fuel gasoline and ethanol engines have efficiencies generally lower than dedicated gasoline engines. Considering ethanol has a few advantages with reference to gasoline, namely the higher-octane number and the larger heat of vaporization, the paper explores the potentials of dedicated pure ethanol engines using the most advanced techniques available for gasoline engines, specifically direct injection, turbo charging and variable valve actuation. Computations are performed with state-of-the-art, well validated, engine and vehicle performance simulations packages, generally accepted to produce accurate results targeting major trends in engine developments. the higher compression ratio and the higher boost permitted by ethanol allows …
Use Of Bio-Ethanol And Bio-Diesel The Key Solution For A More Sustainable Road Transport, Alberto Boretti
Use Of Bio-Ethanol And Bio-Diesel The Key Solution For A More Sustainable Road Transport, Alberto Boretti
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Life Cycle Analysis (LCA) of alternative transportation fuels clearly shows the advantages of reducing the use of nonrenewable fossil fuels vs. renewable biologic novel fuels to reduce the emissions of carbon dioxide. Being based on the natural recycle of carbon dioxide through the use of renewable energy sources, use of these renewable fuels does not imply depletion of natural resources and is therefore sustainable in the long term. Renewable fuels and advanced internal combustion engines and powertrains are the technologies that in addition to be the most likely to produce benefits in term of carbon balance and fossil fuel saving, …
Study Of Turbulence-Chemistry Interaction In Hypersonic Turbulent Boundary Layers, Lian Duan, M. Pino Martín
Study Of Turbulence-Chemistry Interaction In Hypersonic Turbulent Boundary Layers, Lian Duan, M. Pino Martín
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Studies of the turbulence-chemistry interaction (TCI) are performed in hypersonic turbulent boundary layers using direct numerical simulation (DNS) flow fields under typical hypersonic conditions representative of blunt-body and slender-body hypersonic vehicles, with super catalytic and noncatalytic wall conditions in pure air. Nondimensional governing parameters, 'interaction' Damk̈ohler number and relative heat release, are proposed to measure the influence of TCI on flow composition and temperature. Both a priori and posteriori studies are performed to assess the effect of TCI on chemical production rates and mean and turbulence flow characteristics. In addition, an effective approach (called PDF-TS) to estimate the intensity of …
Use Of Bio Ethanol The Key Solution For A More Sustainable Road Transport, Alberto A. Boretti
Use Of Bio Ethanol The Key Solution For A More Sustainable Road Transport, Alberto A. Boretti
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Life Cycle Analysis (LCA) of alternative transportation fuels clearly shows the advantages of reducing the use of nonrenewable fossil fuels vs. renewable synthetic and biologic novel fuels to reduce the emissions of carbon dioxide. Being based on the natural or synthetic recycle of carbon dioxide through the use of renewable energy sources, use of these renewable fuels does not imply depletion of natural resources and is therefore sustainable in the long term. Renewable fuels and advanced internal combustion engines and powertrains are the technologies that in addition to be the most likely to produce benefits in term of carbon balance …
Alternative Crankshaft Mechanisms And Kinetic Energy Recovery Systems For Improved Fuel Economy Of Passenger Cars, Alberto A. Boretti, Joseph Scalzo, Houshang Masudi
Alternative Crankshaft Mechanisms And Kinetic Energy Recovery Systems For Improved Fuel Economy Of Passenger Cars, Alberto A. Boretti, Joseph Scalzo, Houshang Masudi
Mechanical and Aerospace Engineering Faculty Research & Creative Works
The paper presents a novel design of a variable compression ratio advanced spark ignition engine that also permits an expansion ratio that may differ from the compression ratio therefore generating an Atkinson cycle effect. the stroke ratio and the ratio of maximum to minimum in-cylinder volumes may change with load and speed to provide the best fuel conversion efficiency. the variable ratio of maximum to minimum in-cylinder volumes also improves the full load power output of the engine. Brake specific fuel consumption maps are computed for a gasoline engine 2 Liters, in-line four, turbocharged and direct injection showings significant fuel …
Study Of Turbulence-Radiation Interaction In Hypersonic Turbulent Boundary Layers, L. (Lian) Duan, A. M. Feldick, M. P. Martín, M. F. Modest, D. A. Levin
Study Of Turbulence-Radiation Interaction In Hypersonic Turbulent Boundary Layers, L. (Lian) Duan, A. M. Feldick, M. P. Martín, M. F. Modest, D. A. Levin
Mechanical and Aerospace Engineering Faculty Research & Creative Works
In the paper, we conduct direct numerical simulations (DNS) to investigate the effect of turbulence-radiation interaction (TRI) in hypersonic turbulent boundary layers, representative of the Orion crew exploration vehicle (CEV) at peak heating condition during reentry. The radiative transfer equation (RTE) is solved using the tangent slab approximation. 1 The RTE solver is line-by-line (LBL) accurate, making use of a developed efficient spectral database 2 for spectral modeling. A multi-group full-spectrum correlated-k-distribution (FSCK) method 3 is used to reduce the number of RTE evaluations while preserving LBL accuracy. A nondimensional governing parameter to measure the significance of TRI is proposed, …
Assessment Of Turbulence-Chemistry Interaction In Hypersonic Turbulent Boundary Layers, L. (Lian) Duan, M. P. Martín
Assessment Of Turbulence-Chemistry Interaction In Hypersonic Turbulent Boundary Layers, L. (Lian) Duan, M. P. Martín
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Studies of the turbulence-chemistry interaction are performed in hypersonic turbulent boundary layers using direct numerical simulation flow fields under typical hypersonic conditions representative of blunt-body and slender body hypersonic vehicles, with super catalytic and noncatalytic wall conditions in pure air. Nondimensional governing parameters, the interaction Damköhler number and the interaction relative heat release, are proposed to measure the influence of turbulence-chemistry interaction on flow composition and temperature. Both a priori and posteriori studies are performed to assess the effect of turbulence-chemistry interaction on chemical production rates and mean and turbulent flow characteristics. It is found that the governing parameters provide …
A Comparative Verification Of Forecasts From Two Operational Solar Wind Models, Donald C. Norquist, Warner C. Meeks
A Comparative Verification Of Forecasts From Two Operational Solar Wind Models, Donald C. Norquist, Warner C. Meeks
Mechanical and Aerospace Engineering Faculty Research & Creative Works
The solar wind (SW) and interplanetary magnetic field (IMF) have a significant influence on the near‐Earth space environment. In this study we evaluate and compare forecasts from two models that predict SW and IMF conditions: the Hakamada‐Akasofu‐Fry (HAF) version 2, operational at the Air Force Weather Agency, and Wang‐Sheeley‐Arge (WSA) version 1.6, executed routinely at the Space Weather Prediction Center. SW speed (Vsw) and IMF polarity (Bpol) forecasts at L1 were compared with Wind and Advanced Composition Explorer satellite observations. Verification statistics were computed by study year and forecast day. Results revealed that both models’ mean Vsw are …
Bi-Material Attachment Through A Soft Tissue Interfacial System, Y. X. Liu, S. Thomopoulos, Victor Birman, J. S. Li, G. M. Genin
Bi-Material Attachment Through A Soft Tissue Interfacial System, Y. X. Liu, S. Thomopoulos, Victor Birman, J. S. Li, G. M. Genin
Mechanical and Aerospace Engineering Faculty Research & Creative Works
No abstract provided.
Uncertainty Quantification Integrated To Cfd Modeling Of Synthetic Jet Actuators, Srikanth Adya, Daoru Frank Han, Serhat Hosder
Uncertainty Quantification Integrated To Cfd Modeling Of Synthetic Jet Actuators, Srikanth Adya, Daoru Frank Han, Serhat Hosder
Mechanical and Aerospace Engineering Faculty Research & Creative Works
The Point-Collocation Non-intrusive Polynomial Chaos (NIPC) method has been applied to a stochastic synthetic jet actuator problem used as one of the test cases in the CFDVAL2004 workshop to demonstrate the integration of computationally efficient uncertainty quantification to the high-fidelity CFD modeling of synthetic jet actuators. The test case included the simulation of an actuator generating a synthetic jet issued into quiescent air. The Point-Collocation NIPC method is used to quantify the uncertainty in the long-time averaged u and v-velocities at several locations in the flow field due to the uniformly distributed uncertainty introduced in the amplitude and frequency of …
"Pull-In" Of A Pre-Stressed Thin Film By An Electrostatic Potential: A 1-D Rectangular Bridge And A 2-D Circular Diaphragm, Gang Duan, Kai Tak Wan
"Pull-In" Of A Pre-Stressed Thin Film By An Electrostatic Potential: A 1-D Rectangular Bridge And A 2-D Circular Diaphragm, Gang Duan, Kai Tak Wan
Mechanical and Aerospace Engineering Faculty Research & Creative Works
A one-dimensional (1-D) rectangular pre-stressed thin film clamped at two opposite ends is actuated by an electrostatic voltage applied to a pad directly underneath. the pre-stress is allowed to be either tensile or compressive in nature. at a critical applied voltage, the film becomes unstable and makes direct contact with the pad, leading to "pull-in". an elastic model is constructed to account for the phenomenon over ranges of film pad gap and residual stress. the results compare favorably with finite element analysis (FEA) in literature and experimental data and possess distinct advantages over other available closed-form solutions. the model is …
Computer Aided Contour Profiling Of High Strength Deposits, Sriram Praneeth Isanaka, Amar Bala Sridhar, Frank W. Liou, Joseph William Newkirk
Computer Aided Contour Profiling Of High Strength Deposits, Sriram Praneeth Isanaka, Amar Bala Sridhar, Frank W. Liou, Joseph William Newkirk
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Additive manufacturing processes suffer from the effect of ripples, edge rounding and surface variations. To reduce their effect, ideal process parameters for the laser deposition process were investigated. Also, a new method was identified to analyze deposits by accurately plotting their contours. This was achieved through point cloud data of the deposits generated using coordinate measurement and 3D scanning. Curve fitting was performed on the data in Matlab to generate the contours of the deposit. The intercept values, heights, and contact angle of the curves give an indication of the uniformity of deposits and aid in reducing defects.
Selective Laser Sintering Of 13-93 Bioactive Glass, Krishna C. R. Kolan, Ming-Chuan Leu, Greg Hilmas, Mariano Garcia Velez
Selective Laser Sintering Of 13-93 Bioactive Glass, Krishna C. R. Kolan, Ming-Chuan Leu, Greg Hilmas, Mariano Garcia Velez
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Bioactive glasses are more promising than biopolymers in fabricating scaffolds for bone tissue repair because they convert to hydroxyapatite, when implanted in vivo. Both direct and indirect selective laser sintering (SLS) methods of 13-93 bioactive glass were considered in this research to study the feasibility of fabricating scaffolds for bone repair applications. Stearic acid was used as the binder in the indirect method to fabricate the scaffolds. The green scaffolds underwent binder burnout and sintering at various soaking conditions between 675⁰C and 700⁰C, achieving a maximum compressive strength of 23.6 MPa, which is higher than that of the human cancellous …
Laser Based Rapid Manufacturing Of Metallic Gas Diffusion Layers For Pem Fuel Cells, Gargi Tandra, Todd E. Sparks, Shyam Barua, Nikhil P. Kulkarni, Frank W. Liou
Laser Based Rapid Manufacturing Of Metallic Gas Diffusion Layers For Pem Fuel Cells, Gargi Tandra, Todd E. Sparks, Shyam Barua, Nikhil P. Kulkarni, Frank W. Liou
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Gas Diffusion layers (GDL’s) are an essential component of Polymer Electrolyte Membrane Fuel cells (PEMFC’s) which aid in thermal & electrical conductivities, water management and act as backup layers for the membrane electrode assemblies. This paper summarizes the effort to prototype metallic GDL designs using a miniature laser deposition system developed at Missouri University of Science & Technology. The pore sizes are controlled by masking the diverging laser beam using stainless steel masks of varying sizes and shapes. The through pore feature and further treatment of the GDL’s for hydrophobicity reduces the water management issue and thereby increases the performance …
Mea Manufacturing Using An Additive Manufacturing Process To Deposit A Catalyst Pattern In An Mea And Its Impact On Cost Reduction, Nikhil P. Kulkarni, Todd E. Sparks, Gargi Tandra, Frank W. Liou
Mea Manufacturing Using An Additive Manufacturing Process To Deposit A Catalyst Pattern In An Mea And Its Impact On Cost Reduction, Nikhil P. Kulkarni, Todd E. Sparks, Gargi Tandra, Frank W. Liou
Mechanical and Aerospace Engineering Faculty Research & Creative Works
The manufacturing of a fuel cell Membrane Electrode Assembly (MEA) is a significant cost driver in polymer-electrolyte membrane (PEM) fuel cell technologies, primarily due to the inclusion of expensive materials in the catalyst layer. The selective deposition of a catalyst on the MEA of a fuel cell can drastically reduce the costs depending upon the catalyst, method used for deposition, and production volume. In this paper, testing and analysis of a novel catalyst iridium oxide is discussed. The performance of the catalyst will be compared with the conventional catalysts which will give us an estimate of its effectiveness however, in …
Multi-Axis Planning System (Maps) For Hybrid Laser Metal Deposition Processes, Frank W. Liou, Jianzhong Ruan, Todd E. Sparks
Multi-Axis Planning System (Maps) For Hybrid Laser Metal Deposition Processes, Frank W. Liou, Jianzhong Ruan, Todd E. Sparks
Mechanical and Aerospace Engineering Faculty Research & Creative Works
This paper summarizes the research and development of a Multi-Axis Planning System (MAPS) for hybrid laser metal deposition processes. The project goal is to enable the current direct metal deposition systems to fully control and utilize multi-axis capability to make complex parts. MAPS allows fully automated process planning for multi-axis layered manufacturing to control direct metal deposition machines for automated fabrication. Such a capability will lead to dramatic reductions in lead time and manufacturing costs for high-value, low-volume components with high performance material. The overall approach, slicing algorithm, machine simulation for planning validation, and the planning results will be presented.
Optimization Of Selective Laser Sintering Process For Fabrication Of Zirconium Diboride Parts, Ming-Chuan Leu, Shashwatashish Pattnaik, Greg Hilmas
Optimization Of Selective Laser Sintering Process For Fabrication Of Zirconium Diboride Parts, Ming-Chuan Leu, Shashwatashish Pattnaik, Greg Hilmas
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Selective Laser Sintering (SLS) was investigated to fabricate Zirconium Diboride (ZrB2) parts for ultra-high temperature applications. Experiments were conducted to determine values of SLS process parameters (laser power, scan speed, line spacing, and layer thickness) that can be used to build ZrB2 parts with high integrity and sharp geometrical features. A sacrificial plate with a proper number of layers (determined from experimentation) separated from the main part was built in order to reduce thermal gradients when building the main part. The sacrificial plate was found to assist in eliminating cracks in the bottom of the main part. …
Development Of A Low Cost Imaging System For A Laser Metal Deposition Process, Shyam Barua, Todd E. Sparks, Frank W. Liou
Development Of A Low Cost Imaging System For A Laser Metal Deposition Process, Shyam Barua, Todd E. Sparks, Frank W. Liou
Mechanical and Aerospace Engineering Faculty Research & Creative Works
The size of the melt pool created by the laser is one of the most important quality characteristic in a laser metal deposition process. This paper discusses the development of a low-cost vision system to automatically determine the size of the melt pool for in-process control. To cope with the intense infrared signal from the laser and melt pool, external ultraviolet illumination is paired with narrow bandpass filters on a usb microscope to achieve a clear image of the melt pool. The sensitivity of the melt pool to changes in system parameters and various substrate materials are also evaluated.
Effect Of Different Graphite Materials On Electrical Conductivity And Flexural Strength Of Bipolar Plates Fabricated By Selective Laser Sintering, Nannan Guo, Ming-Chuan Leu
Effect Of Different Graphite Materials On Electrical Conductivity And Flexural Strength Of Bipolar Plates Fabricated By Selective Laser Sintering, Nannan Guo, Ming-Chuan Leu
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Graphite is an excellent material for bipolar plates used in Proton Exchange Membrane (PEM) fuel cell due to its great chemical resistance, but the brittle nature makes it difficult to manufacture. Selective Laser Sintering (SLS) based on layer-by-layer manufacturing technology can fabricate graphite bipolar plates with complex gas flow channels. To improve the performance of bipolar plates including electrical conductivity and flexural strength, different graphite materials (natural graphite, synthetic graphite, carbon black, and carbon fiber) were investigated to fabricate test samples. These samples then went through post processing including carbonization and infiltration. The results show that bipolar plates with electrical …
Selective Laser Sintering And Freeze Extrusion Fabrication Of Scaffolds For Bone Repair Using 13-93 Bioactive Glass: A Comparison, Krishna C. R. Kolan, Nikhil P. Doiphode, Ming-Chuan Leu
Selective Laser Sintering And Freeze Extrusion Fabrication Of Scaffolds For Bone Repair Using 13-93 Bioactive Glass: A Comparison, Krishna C. R. Kolan, Nikhil P. Doiphode, Ming-Chuan Leu
Mechanical and Aerospace Engineering Faculty Research & Creative Works
13-93 glass is a third-generation bioactive material which accelerates the bone’s natural ability to heal by itself through bonding with surrounding tissues. It is an important requirement for synthetic scaffolds to maintain their bioactivity and mechanical strength with a porous internal architecture comparable to that of a human bone. Additive manufacturing technologies provide a better control over design and fabrication of porous structures than conventional methods. In this paper, we discuss and compare some of the common aspects in the scaffold fabrication using two such processes, viz. selective laser sintering (SLS) and freeze extrusion fabrication (FEF). Scaffolds fabricated using each …
Uncertainty Analysis In Laser Deposition Finish Machining Operations, Jomy Francis, Todd E. Sparks, Frank W. Liou
Uncertainty Analysis In Laser Deposition Finish Machining Operations, Jomy Francis, Todd E. Sparks, Frank W. Liou
Mechanical and Aerospace Engineering Faculty Research & Creative Works
The Laser Aided Manufacturing Process (LAMP) from Missouri S&T is a laser based metals rapid manufacturing process that uses machining to improve the final part's surface finish. When free-form machining, the absence of enough deposited material results in inconsistent scallop heights which result in poor surface finish or incorrect geometry in the final part. This paper investigates a probabilistic approach to various uncertainties involved in the deposition and subsequent machining of an arbitrary part. Furthermore, this paper analyses the machine errors which makes the response of Scallop Height to exceed the predefined maximum scallop height when traveling along the tool …
Investigations Of Femtosecond-Nanosecond Dual-Beam Laser Ablation Of Dielectrics, Cheng Hsiang Lin, Zheng Hua Rao, Lan Jiang, Wu Jung Tsai, Ping Han Wu, Chih Wei Chien, Shean Jen Chen, Hai Lung Tsai
Investigations Of Femtosecond-Nanosecond Dual-Beam Laser Ablation Of Dielectrics, Cheng Hsiang Lin, Zheng Hua Rao, Lan Jiang, Wu Jung Tsai, Ping Han Wu, Chih Wei Chien, Shean Jen Chen, Hai Lung Tsai
Mechanical and Aerospace Engineering Faculty Research & Creative Works
We have conducted experimental investigations for the micromachining of dielectrics (fused silica) using an integrated femtosecond (is) and nanosecond (ns) dual-beam laser system at different time delays between the fs and ns pulses. We found that the maximum ablation enhancement occurs when the fs pulse is shot near the peak of the ns pulse envelope. Enhancements up to 13.4 times in ablation depth and 50.7 times in the amount of material removal were obtained, as compared to fs laser ablation alone. the fs pulse increases the free electron density and changes the optical properties of fused silica to have metallic …
Automated Residential Energy Monitoring: An Approach To Performance Comparisons, Christopher D. Wright, Robert B. Stone
Automated Residential Energy Monitoring: An Approach To Performance Comparisons, Christopher D. Wright, Robert B. Stone
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Techniques for residential energy usage monitoring is an emerging field that is currently drawing significant attention. This paper is a description of the current efforts to monitor and compare the performance of three solar-powered homes built at Missouri University of Science and Technology. the homes are outfitted with an array of sensors and a data logger system to measure and record electricity production, system energy use, internal home temperature and humidity, hot water production, and exterior ambient conditions the houses are experiencing. Data will be collected to measure the performance of the houses, compare to energy modeling programs, design and …
Validating Module Heuristics On Large Scale Products, Rachel Day, Robert B. Stone, Katie Grantham Lough
Validating Module Heuristics On Large Scale Products, Rachel Day, Robert B. Stone, Katie Grantham Lough
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Decreasing time and costs is a major objective in many businesses today. Including modularity in the early design phases can effectively decrease time spent on and costs associated with a project. the task of identifying modules within a product early in the design process (when decisions are less expensive) is made less daunting by using the techniques of functional modeling and module heuristics. This paper discusses the results of the initial efforts to verify the module heuristics on large products (products with functional models consisting of more than 30 sub-functions) since the module heuristics were originally developed on small products. …
Functioncad: A Functional Modeling Application Based On The Function Design Framework, Robert L. Nagel, Kenneth L. Perry, Robert B. Stone, Daniel A. Mcadams
Functioncad: A Functional Modeling Application Based On The Function Design Framework, Robert L. Nagel, Kenneth L. Perry, Robert B. Stone, Daniel A. Mcadams
Mechanical and Aerospace Engineering Faculty Research & Creative Works
This paper presents a functional modeling application, Function CAD, based on integrated functional and process modeling within the Function Design Framework. Function CAD provides for mixed, hierarchical models of environment, process and function with relationships represented via flows of material, energy and signal. This paper discusses the technical details of the Function CAD software including its two major components: (1) the library, libFCAD, for handling the internal representation of the model and (2) the GUI for user-Based model manipulation and visualization. the application of Function CAD within a computational, function- based conceptual design process is discussed along with the plugin …
Prediction Of The Transport Properties Of A Polyatomic Gas, Zhi Liang, Hai-Lung Tsai
Prediction Of The Transport Properties Of A Polyatomic Gas, Zhi Liang, Hai-Lung Tsai
Mechanical and Aerospace Engineering Faculty Research & Creative Works
An Ab Initio Molecular Potential Model is Employed in This Paper to Show its Excellent Predictability for the Transport Properties of a Polyatomic Gas from Molecular Dynamics Simulations. a Quantum Mechanical Treatment of Molecular Vibrational Energies is Included in the Green and Kubo Integral Formulas for the Calculation of the Thermal Conductivity by the Metropolis Monte Carlo Method. using CO2 Gas as an Example, the Fluid Transport Properties in the Temperature Range of 300-1000 K Are Calculated Without using Any Experimental Data. the Accuracy of the Calculated Transport Properties is Significantly Improved by the Present Model, Especially for the Thermal …