Fri Mar 21 17:04:39 2014 UTClccn-n878385440.23Modeling mantle convection using an internal state variable model framework0.460.47Mississippi State College mechanical engineering graduates, class of 1949137300521n 878385442186564Mississippi State University. Dept. of Mechanical EngineeringcontainsVIAFID/131060479Mississippi State UniversitycontainsVIAFID/126763134Mississippi State University. Mechanical and Nuclear Engineering Departmentnc-mississippi state universityMississippi State Universitynp-carley, c tCarley, C. T.lccn-n87112782Forbes, Richard E.lccn-no2011034886Bell, Charles Jamesnc-george c marshall space flight center$propulsion and vehicle engineering laboratoryGeorge C. Marshall Space Flight CenterPropulsion and Vehicle Engineering Laboratorylccn-n92027931Holmes, Alester G.(Alester Garden)1876-1953lccn-n81078577Smith, G. V.lccn-nr2002019240Dickson, W. E.lccn-n84212472Mississippi State UniversityEngineering & Industrial Research Stationnp-eastland, d m$david meadeEastland, D. M.(David Meade)Mississippi State UniversityDepartment of Mechanical EngineeringHandbooks, manuals, etcPeriodicalsMississippi State University.--Department of Mechanical EngineeringMississippi State UniversityMississippiVibrationHeat--ConvectionComposite materials--Mechanical propertiesEducation--CurriculaCollege studentsStudentsStructural analysis (Engineering)Composite materials--Mathematical modelsBuildings--Environmental engineeringMetal-cutting--Computer simulationRock deformationBiodiesel fuelsElastic plates and shells--VibrationAdult services in public libraries--EvaluationEngineering--Study and teachingMechanical engineeringLaminated materials--Mathematical modelsDiesel fuelsNanoparticlesOscillationsAir conditioning--Equipment and supplies--Computer simulationDegrees, AcademicHeat engineeringMolecular dynamics--Computer simulationPropane as fuelDeformations (Mechanics)--Mathematical modelsMechanical engineering--Study and teachingCooling--Mathematical modelsAutomobiles--Materials--TestingStrength of materials--Simulation methodsFinite element methodEnergy conservation--Mathematical modelsUnited StatesAutomobiles--CrashworthinessBladesLaminated materials--VibrationMethanePower (Mechanics)Shells (Engineering)--VibrationRocket engines--ThrustLaminated materials--Mechanical propertiesHeating--Equipment and supplies--Computer simulationEarth (Planet)19491954196419671976198119821986199620022006200820102011201330262922ocn025535354book19670.47Bishop, Edward HVibration effects on heat transfer in cryogenic systems : final report11ocn019063216book19640.47Mississippi State UniversityA proposal for the establishment of a doctorial program in mechanical engineering [at] Mississippi State University11ocn031057333book19820.47Jeng, Yaug-FeaThe Design of a fourth scale model oscillation system for a bulldozer blade11ocn025559019book0.47Carley, C. TVibration effects on heat transfer in cryogenic systems : interim progress report NAS8-2028411ocn018452459serial0.47ASME reportPeriodicals11ocn009440194book19810.47Eastland, D. MLaboratory manual for ME 1021 experimental orientationHandbooks, manuals, etc11ocn015645129book19860.47Mississippi State UniversityThe Doctor of philosophy program in mechanical engineering at Mississippi State University22ocn320851478serial0.47Mississippi State UniversityAnnual report21ocn005192883book19490.47Mississippi State UniversityMississippi State College mechanical engineering graduates, class of 1949Directories22ocn022232486book0.47Mississippi State UniversityAreas of interest and capabilities for research11ocn051962542com20020.47Wince, Jaton NakiaModeling chip formation in orthogonal metal cutting using finite element analysisDissertations, AcademicThis thesis presents the simulation of chip formation in orthogonal metal cutting to evaluate the predictive capabilities of finite element code DYNA 3D. The Johnson and Cook constitutive model for materials, OFHC Copper, Aluminum 2024 T351, and Aluminum 6061 T6 alloy were incorporated into the simulation to account for the effects of strain hardening, strain rate hardening, and thermal softening effects during machining. Calculated values for the Johnson and Cook constitutive constants for Aluminum 6061 T6 alloy were determined from the literature. The model was compared to experimentally measured shear angles, chip thickness, chip velocity, and forces from the literature to evaluate the accuracy of the finite element code for a range machining strain rates. In an attempt to determine the predictive capabilities of DYNA 3D a strain rate regime of 10+3 s-1 to 10+4 s-1 was defined as the optimal strain rate regime for the orthogonal metal cutting application11ocn772028206com20110.47Shoemaker, Nicholas ThaneDual-fueling concepts a comparison of methane and propane as primary fuels with biodiesel and ultra-low sulfur diesel as separate pilot fuelsThe goal of this thesis is to examine dual-fueling concepts using two different types of primary fuel, methane and propane; as well as two different pilot fuels, ultra-low sulfur diesel (ULSD) and biodiesel (B100). Experiments were performed using a 1.9 liter, turbocharged, 4 cylinder diesel engine at 1800 rev/min with ULSD and B100 being injected as a pilot fuel directly into the combustion chamber, at different brake mean effective pressures (BMEP), and percent energy substitutions of propane and methane. Brake thermal efficiency (BTE) and emissions (NOx, THC, CO, CO₂, O₂ and smoke) were also measured and analyzed. Maximum PES was limited by misfire at 2.5 bar, 5.0 bar, 7.5 bar, BMEP for all cases and knock at 10 bar BMEP for both B100-propane and ULSD-propane. In general dual fueling was shown to be beneficial for lowering NOx, CO₂, and smoke emissions along with, in some cases, showing improvements in BTE11ocn625447798com20060.47Stone, Tonya WilliamsMolecular dynamics simulations of nanoparticle interactionsMolecular dynamics simulations using the Embedded Atom Method were performed to describe the interparticle behavior of two single crystal spherical nickel nanoparticles during compaction based on applied strain rate, particle size, contact angle, and crystal orientation. The evolution of the contact surfaces was analyzed during the molecular dynamics simulation and an investigation of friction effects was conducted at the contact surfaces. The results from the current study were validated by comparing them to previous nanocrystalline research on bulk particle deformation and to previous studies of elasto-plastic contact laws between two macroscale spherical particles. These quantified friction effects give a better understanding of nanoparticle behavior and will be used to develop constitutive equations for larger scale models, such as finite element analysis11ocn654958456com20100.23Sherburn, Jesse AndrewModeling mantle convection using an internal state variable model frameworkIn the current study we developed an internal state variable (ISV) model based on the Bammann inelasticity internal state variable model (BIISV) to include damage, recrystallization, and texture development, which we then implemented into a mantle convection code, TERRA2D, to incorporate higher fidelity material behavior into mantle convection simulations. With experimental stress strain data found in the literature model constants for the BIISV model were determined for a number of geologic materials. The BIISV model was shown to be far superior to the steady state power law model currently used by the geologic community to capture the deformation of geologic materials. Once implemented and verified in TERRA2D the BIISV model revealed locations of hardened material that behaved like diverters in the cold thermal boundary layer that the power law model could never produce. These hardened regions could be a plausible reason for the current subduction zones present on the earth. We then altered the BIISV model equation to include the effects of damage, recrystallization, and texture development in order to model possible weakening mechanisms in the cold thermal boundary layer of the mantle. Inclusion of damage and recrystallization allowed the cold thermal boundary layer to mobilize and plunge downward into the hotter region below. Texture development increased the intensity of rotational flow within the hotter zone as cold boundary material plunged downward which aided in destabilizing the cold upper thermal boundary layer. The inclusion of an internal state variable model with damage, recrystallization, and texture development represents a significant advancement in handling deformational physics for mantle phenomena in a comprehensive, unified, and automatic manner11ocn606014570com20080.47Stinson, Joel HCrystal plasticity modeling of structural magnesium alloys under various stress statesIn this work, a crystal elasto-viscoplastic model was modified to account for the anisotropic mechanical response of magnesium aluminum alloys. Crystal plasticity may offer new understanding of these alloys by explicitly modeling the texture development that profoundly affects the properties of magnesium. The model is able to account for the individual slip systems of both the cubic and hexagonal phases. The constants of the model were determined from published experimental AZ31 data, and the plastic hardening response is shown to match these results well using a modification to the hardening rule to approximate the kinetics of twinning. Model aggregates were created with aluminum compositions representative of common magnesium structural alloys. This approach allows the effect of varying percentage of cubic phase on the hexagonal magnesium alloy aggregate to be studied both in terms of macroscopic response and the crystallographic changes occurring within the system11ocn606013756com20080.47Carrasquel Romero, Isha CStructure-property quantification and modeling related to crashworthinessThe objective of this study is to characterize critical component structure-properties on a Dodge Neon for material response refinement in crashworthiness simulations. Crashworthiness simulations using full-scale finite element (FE) vehicle models are an important part of vehicle design. According to the National Highway Traffic Safety Administration (NHTSA), there were over six million vehicle crashes in the United States during 2004, claming lives of more than 40,000 people. Crashworthiness simulations on a detailed FE model of a 1996 Plymouth/Dodge Neon were conducted on the NHTSA for different impact crash scenarios. The top-ten energy-absorbing components of the vehicle were determined. Material was extracted from the as-built vehicle and microstructural analyses were conducted. Tension tests at different temperatures and strain rates were performed as well as microhardness tests. Different microstructural spatial clustering and mechanical properties were found for diverse vehicle components. A plasticity model based on microstructure was used to predict the material response of the front bumper11ocn606017136com20080.47Fumo, NelsonCooling, heating, and power systems energy performance and non-conventional evaluation based on energy useCooling, Heating and Power (CHP) systems have been recognized as a key alternative for thermal energy and electricity generation at or near end-user sites. CHP systems can provide electricity while recovering waste heat to be used for space and water heating, and for space cooling. Although CHP technology seems to be economically feasible, because of the constant fluctuations in energy prices, CHP systems cannot always guarantee economic savings. However, a well-designed CHP system can guarantee energy savings, which makes necessary the quantification of nonconventional benefits from this technology in order to offset any economic weakness that can arise as consequence of energy prices. Some aspects that could be included in a nonconventional evaluation are: building energy rating, emission of pollutants, power reliability, power quality, fuel flexibility, brand and marketing benefits, protection from electric rate hikes, and benefits from promoting energy management practices. This study focuses on two aspects: building energy rating and emission reduction of pollutants, related to CHP system energy performance. Two methodologies have been developed in order to estimate the energy related benefits from CHP technology. To determine the energy performance, a model has been developed and implemented to simulate CHP systems in order to estimate the building-CHP system energy consumption. The developed model includes the relevant variables governing CHP systems such as: type and size of the components, individual component efficiencies, system operating mode, operational strategy, and building demand for power, heating, and cooling. The novelty of this model is the introduction of the Building Primary Energy Ratio (BPER) as a parameter to implement a primary energy operational strategy, which allows obtaining the best energy performance from the building-CHP system. Results show that the BPER operational strategy always guarantees energy savings. On the other hand, results from a cost-oriented operational strategy reveal that for critical design conditions, high economic savings can be obtained with unacceptable increment of energy consumption. For Energy Star Rating and Leadership in Energy and Environmental Design (LEED) Rating, results show that CHP systems have the ability to improve both ratings11ocn002748105book19540.47Mississippi State UniversityMaterial assembled for E.C.P.D. [Engineers' Council for Professional Development] Inspecting Committee11ocn772028203com20110.47Asadi, EbrahimStatic and free vibration analyses of composite shells based on different shell theoriesEquations of motion with required boundary conditions for doubly curved deep and thick composite shells are shown using two formulations. The first is based upon the formulation that was presented initially by Rath and Das (1973, J. Sound and Vib.) and followed by Reddy (1984, J. Engng. Mech. ASCE). In this formulation, plate stiffness parameters are used for thick shells, which reduced the equations to those applicable for shallow shells. This formulation is widely used but its accuracy has not been completely tested. The second formulation is based upon that of Qatu (1995, Compos. Press. Vessl. Indust.; 1999, Int. J. Solids Struct.). In this formulation, the stiffness parameters are calculated by using exact integration of the stress resultant equations. In addition, Qatu considered the radius of twist in his formulation. In both formulations, first order polynomials for in-plane displacements in the z-direction are utilized allowing for the inclusion of shear deformation and rotary inertia effects (first order shear deformation theory or FSDT). Also, FSDTQ has been modified in this dissertation using the radii of each laminate instead of using the radii of mid-plane in the moment of inertias and stress resultants equations. Exact static and free vibration solutions for isotropic and symmetric and anti-symmetric cross-ply cylindrical shells for different length-to-thickness and length-to-radius ratios are obtained using the above theories. Finally, the equations of motion are put together with the equations of stress resultants to arrive at a system of seventeen first-order differential equations. These equations are solved numerically with the aid of General Differential Quadrature (GDQ) method for isotropic, cross-ply, angleply and general lay-up cylindrical shells with different boundary conditions using the above mentioned theories. Results obtained using all three theories (FSDT, FSDTQ and modified FSDTQ) are compared with the results available in literature and those obtained using a three-dimensional (3D) analysis. The latter (3D) is used here mainly to test the accuracy of the shell theories presented here11ocn772028237com20110.47Qiu, LuDevelopment of sub models for a phenomenological investigation of diesel engine combustionVarious sub models of a multi-zone phenomenological model are developed by incorporating Dec's conceptual model and Siebers' mixing limited theory and validated with experiments. The spray penetration model, liquid length model and lift-off length model are verified with experiment data. The ignition delay model is then validated with experiment data at different injection timings and loads. The air entrainment model is based on Siebers' jet theory. Sub models for the premixed heat release rate and diffusion burn rate are also included. The overall phenomenological model is at first used to match the motoring pressure curve. The important sub models are well validated independently and the phenomenological model is useful in simulating diesel spray combustion. Future work is needed to integrate these sub models and to resolve existing issues in temperature profiles of the preparing zone and liquid zone11ocn053101183serial0.47Mississippi State UniversitySyllabi of required courses in Mechanical Engineering curriculum11ocn772028267com20110.47Hajianmaleki, MehdiStatic and vibration analysis of thick generally laminated composite deep curved beamsA rigorous first order shear deformation theory (FSDT) is employed along with modified ABD parameters to analyze static and free vibration behavior of generally laminated beams and shafts. Different approaches for calculating composite beam stiffness parameters have been considered and the most accurate one that accounts for material couplings have been used to analyze static and free vibration behaviors of straight beams with different laminates and boundary conditions. In order to analyze curved beams, the term (1+z/R) is exactly integrated into ABD parameters formulation and an equivalent modulus of elasticity is used instead of traditional stiffness terms to account for both the deepness and material coupling of the beam structures. The model has been solved analytically for simply supported boundary conditions and the general differential quadrature (GDQ) technique has been used for other boundary conditions. The results for deflection, moment resultants, and natural frequencies of straight and curved beams with different deepness ratio (often called depth ratio), slenderness ratio, lamination, and boundary conditions are compared with those obtained from accurate three dimensional finite element simulations using ANSYS. The results were in close proximity to three dimensional finite element results. The model is then applied to transverse vibration analysis of multi-span generally laminated composite shafts with a lumped mass using GDQ. The results for natural frequencies are compared to experimental and other analytical models as well as finite element simulation. The results in the present analyses were found accurate. Conclusively, it has been shown that when considering more accurate stiffness parameters, a First Order Shear Deformation Theory can accurately predict static and free vibration behaviors of composite beams and multispan shafts of any deepness, lamination and boundary conditions11ocn317503629com20060.47Stone, Nicholas AlexanderInstallation and instrumentation of a micro-CHP demonstration facilityMicro-Cooling, Heating and Power (CHP) is the decentralized generation of electricity in which normally wasted heat is recovered for use in heating and cooling of the space. A micro-CHP demonstration facility is needed to showcase the system and allow for experiments to be performed. This thesis illustrates the steps taken for the installation and instrumentation of a Micro-CHP (Cooling, Heating, and Power) demonstration facility. Equipment sizing was performed by creating an accurate building model and performing a transient building analysis. Temperature, pressure, flow rate, and relative humidity are measured in order to determine accurate energy balances through each piece of equipment in the micro-CHP system. The data is collected using a number of LabView subroutines while a Visual Basic program was developed to display the information11ocn036125695book19960.47Chenevert, Donald JamesUncertainty in calculated performance of hybrid rocket motors11ocn772028281com20130.47Murray, Darryl VincentModeling carbon fiber reinforced polymeric composite laminates for piezoelectric morphing structuresThin unsymmetric carbon fiber reinforced polymeric (CFRP) composite laminates are examined for use of morphing structures using piezoelectric actuation. During fabrication, unsymmetric laminates are able to deform to more than one post-cure room temperature shape. Thin cross-ply laminates will deform to a cylindrical post-cure room temperature shape while thicker non-cross-ply laminates will deform to a saddle shape. Predictions of the deformed post-cure shape will be made by modeling the cure process using analytical and numerical. These models will then serve as expectations for experimental tests. Modeling the fabrication process allowed for characterizing important data such as residual stresses from the cure process, room temperature shapes, and bi-stability of the CFRP composite laminates all of which are needed to accurately model morphing structures. Cross-ply laminates will deform to a symmetric cylindrical shape, cylindrical shape I, after the cure process. Non cross-ply laminates will deform to a non-uniform saddle shape after the cure process. These post-cure room temperature deformation shapes can be used as morphing structures by applying a force large enough to create "snap" through to the other cylindrical shape, cylindrical shape II. A piezoelectric actuator, bonded to the deformed room temperature shapes, is used to generate this "snap through force". Experimental verification was done by fabricating the CFRP composite laminates and comparing the post cure room temperature shapes to the analytical and numerical fabrication models. For morphing structures, experimental verification was done by actuating the piezoelectric actuator and comparing the deformation of cylindrical shape II to analytical and numerical piezoelectric models11ocn003252771book19760.47Holmes, Alester GA short history of the Mechanical Engineering Department of Mississippi State University of Agriculture and Applied Sciences, 1892-1976HistoryFri Mar 21 15:14:09 EDT 2014batch28877