| Highly Sensitive and Robust Damage Detection of Periodic Structures with Piezoelectric Networking |
May-2008 |
14 pages |
| Authors:
Kon-Well Wang; Jiong Tang; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
 | Damage detection in engine bladed disks is often performed through ultrasonic and eddy current techniques that are reliable, but expensive and lack in-situ monitoring capability. Alternatively, vibration-based damage detection methods are relatively inexpensive, have real-time in-situ potential, but are generally inaccurate due to low sensitivity. The goal of this research is to advance the state-of-the-art of vibration-based damage detection of bladed disks by utilizing the unique vibration localization characteristics of ... |
|
| Plasma-Propellant Interaction Studies |
20 DEC 2007 |
24 pages |
| Authors:
Stefan T. Thynell; Thomas A. Litzinger; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| This report describes research focused on the interactions between a plasma and a solid propellant. The specific issues addressed include the effects of radical and neutral species as well as radiative heat transfer on the ignition and combustion of double-base propellants. A wide variety of measurements have been conducted using a broad range of diagnostic tools, such as a triple-quadrupole mass spectrometer, special heat flux gages, high-speed cameras, as well ... |
|
| An Augmented Computer User Login Authentication Using Classifying Regions of Keystroke Density Neural Network |
Sep 2005 |
|
| Authors:
PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
 | We present an authentication system using classifying regions of keystroke density based on a neural network architecture with two types of connections: (1) weight vector W and (2) dispersion vector V. In the learning phase, the weight vector W adapts to users' keystroke exemplars, and dispersion vector V adapts to dispersion in the users' keystrokes. Here W represents users' keystroke pattern, and V represents the radius for the regions of ... |
|
| Liquid-Propellant Rocket Engine Injector Dynamics and Combustion Processes at Supercritical Conditions |
NOV 2004 |
251 pages |
| Authors:
Vigor Yang; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| The present AFOSR project focuses on the theoretical modeling and numerical simulation of liquid-propellant rocket engine injector flow and combustion dynamics. Emphasis is placed on cryogenic propellants in both shear and swirl co-axial injectors at supercritical conditions. The formulation is based on the full conservation equations in three dimensions, and accommodates variable properties and finite-rate chemical kinetics. Full account is taken of various high-pressure phenomena such as thermodynamic non- idealities ... |
|
| Wide-Range Robust Control of Combustion Instability |
JUN 2001 |
14 pages |
| Authors:
Boe-Shong Hong; Vigor Yang; Asok Ray; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| This paper presents the concept and design of a two-layer robust control system for suppression of combustion instabilities over a wide range of operation. The control law synthesis based on a multiple-time-scale model of combustion dynamics. Control actions on the fast-time scale are provided by secondary fuel injection realized as modulation of the primary fuel flow and are gain-scheduled according to the variations of mean-flow temperature and velocity on the ... |
|
| Liquid-Propellant Droplet Combustion and Cluster-Behavior at Supercritical Conditions |
MAY 2001 |
214 pages |
| Authors:
Yigor Yang; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| A systematic investigation of superoritical droplet vaporization and cluster behavior has been conducted based on the complete conservation equations in both the gas and liquid phases. The research work addresses a variety of fundamental issues related to droplet vaporization and dynamics at realistic conditions typical of liquid-propellant rocket combustion devices. A unified treatment of real-fluid thermodynamics has been developed based on fundamental theories. Special attention was given to the thermodynamic ... |
|
| Applications of New Concepts in Scientific Analysis to Atmospheric Studies |
13 DEC 2000 |
3 pages |
| Authors:
James G. Brasseur; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| The diffusion of passive scalar pollutants in the atmosphere can constitute serious environment hazards. Recent studies have pointed to the increased danger associated with extremely high instantaneous point concentrations. We analyzed the local turbulence structure underlying statistical descriptions of turbulent diffusion. Specifically, we analyzed the entrainment of passive scalar across a buoyancy-driven convective boundary layer (CBL) capping inversion using 963 and 1283 large-eddy simulation (LES). In the simulations, a uniform ... |
|
| The Effect of Turbulence on Droplet Drag, Dispersion, Vaporization and Secondary Breakup in Diesel Fuel Sprays |
15 JUL 1999 |
6 pages |
| Authors:
D. A. Santavicca; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| Results are presented from an experimental study of droplet phenomena in diesel engine and gas turbine combustor simulated flows. Three specific phenomena have been studied: (1) the use of exciplex fluorescence to characterize the vaporization of liquid droplets in unsteady flows, (2) the enhanced secondary breakup of liquid droplets in flows with intense turbulence, and (3) the behavior of liquid jets injected into supercritical environments. |
|
| Combustion Enhancements in Advanced Liquid Rocket Engines |
17 MAY 1999 |
43 pages |
| Authors:
Robert J. Santoro; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| A series of liquid jet experiments, utilizing water as the working fluid and an optically accessible orifice with a LID ratio of 2.5, were performed using laser velocimetry to map the velocity profile at several locations within the orifice. Additional measurements were also made downstream of the orifice exit in the free jet. Finally, measurements were made for a 300 angled orifice to more closely simulate actual injector conditions. The ... |
|
| An Investigation into Computer Simulation of the Dynamic Response of a Gas Turbine Engine |
JUL 1997 |
52 pages |
| Authors:
Todd B. Henricks; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| Transient performance of gas turbines has a strong bearing on output and component life. For this reason, several articles have been written on the dynamic simulation of gas turbine systems in electrical generation, cogeneration, and marine applications. These models provide a basis for this present work. This paper describes a mathematical and computer model that was developed to investigate the dynamic response of a simple (no reheat, regeneration, or other ... |
|
| Computational Modeling of Marine Propulsors |
MAR 97 |
9 pages |
| Authors:
Charles L. Merkle; Jinzhang Feng; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| At the start of this research effort, extensive numerical computations with Navier-Stokes equations for marine propulsors were not routinely conducted anywhere. Now with the advent of much improved computer resources, these computations are carried out regularly to study the complex flow fields, to improve existing designs, and to guide new designs. Looking ahead, computational modeling of marine propulsors has turned a new page. More efficient, more reliable and more robust ... |
|
| Turbine Engine Diagnostics (TED) for Army Tank Applications |
DEC 96 |
61 pages |
| Authors:
Mark J. Pincoski; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| Turbine engine diagnostics have been vastly improved with the use of Artificial Intelligence (AI) techniques such as expert systems artificial neural networks and fuzzy logic. A typical system that is using artificial intelligence to improve its diagnostic capabilities is the Army's Turbine Engine Diagnostic (TED) program for the Ml Abram's AGT-1500 turbine engine. TED is a diagnostic expert system that assists the Ml Abrams mechanic. The system provides assistance during ... |
|
| Chemical Mechanistic Approaches for the Suppression of Soot Formation in the Combustion of High Energy Density Fuels |
SEP 96 |
54 pages |
| Authors:
R. J. Santoro; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| Significant advantages can be gained by the use of high energy density fuels in volume limited applications. However, excessive soot formation that accompanies the combustion of these fuels presently limits their application. Fuel additive approaches prove attractive as they require minimal modifications to already existing equipment. In the present study, a variety of flame configurations were used to study the additive effects on soot formation. Through tests conducted on laminar ... |
|
| Swirl Effects on Coaxial Injector Atomization |
AUG 96 |
96 pages |
| Authors:
Robert J. Santoro; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| The focus of this AASERT grant was the investigation of atomization processes for swirl coaxial gas/liquid spray injection for rocket combustor applications. The work has included review and analysis of atomization literature for swirled and non-swirled gas/liquid sprays, design and fabrication of a rocket-scale swirl coaxial injector for research, and cold-flow and hot- fire characterizations of atomization and combustion with the designed injector. Two significant findings have emerged from the ... |
|
| Semi-Active Vibration Controls of Flexible Structures via Adaptive Materials |
20 JUL 96 |
19 pages |
| Authors:
K. W. Wang; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| The objective of this research is to develop, validate and evaluate novel semi-active and active-passive hybrid structures for real-time vibration suppressions. These types of structures normally require less power than the purely-active systems. Also, since energy is almost always being dissipated, they are more stable than the active approach in other words, they have the advantages of both the passive (stable, low power requirement, fail-safe) and active (high performance, feedback ... |
|
| Ignition and Flame Spreading Susceptibility of Gun Propellants |
30 JUN 96 |
18 pages |
| Authors:
Kenneth K. Kuo; Stefan T. Thynell; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| This work represents the results of a series of tests on ignition and flame spreading processes of gun propellants. The overall effort was split into three tasks: (1) partially confined hot fragment conductive ignition (HFCI) characteristics of high energy, low vulnerability (HELOVA) propellants, (2) shock impact studies on HELOVA propellants, and (3) combustion of layered gun propellants. Results indicated that measured and calculated go/no-go ignition boundaries for XM49 and M43 ... |
|
| Turbulence Flame Interactions - AASERT |
APR 96 |
8 pages |
| Authors:
D. A. Santavicca; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| Two students were supported under the Department of Defense Augmentation Awards for Science and Engineering Research Training (AASERT) program. Mr. Mark McMurray was supported from 15 August 1992 through 14 August 1994, and Mr. Christopher Jones was supported from 15 August 1994 through 14 August 1995. Mark McMurray completed his M.S. degree and accepted employment at Champion Spark Plug Company. Chris Jones expects to complete the requirements for his M. ... |
|
| Detailed Studies of Soot Formation in Laminar Diffusion Flames for Application to Modeling Studies |
30 JAN 96 |
104 pages |
| Authors:
Robert J. Santoro; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| An investigation of soot formation in laminar diffusion flames showed that soot particle surface growth under laminar diffusion flame conditions ceases because of the depletion of hydrocarbon species and not soot particle reactivity loss due to thermal aging of the particles. This result was obtained through direct species concentration measurements under well-controlled conditions, while the particle reactivity effects were calculated based on premixed flame results along with particle temperature/time information ... |
|
| Surface Reactivity of Combustion Generated Soot Particles |
20 OCT 95 |
27 pages |
| Authors:
Robert J. Santoro; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| The focus of this AASERT grant was the development of two novel measurement approaches for soot property characterization: laser-induced incandescence and intrusive probe sampling of soot particles from diffusion flames. Characterization of the laser-induced incandescence technique for soot particle measurements in laminar diffusion flames resulted in the development of a new quantitative measurement technique for soot volume fraction and marked the first use of this technique for quantitative measurements. In ... |
|
| The Effect of Turbulence on Vaporization and Mixing in Fuel Sprays |
08 FEB 95 |
9 pages |
| Authors:
Domenic A. Santavicca; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| An experimental study of droplet-turbulence interactions under simulated fuel spray conditions has been conducted. The behavior of individual droplets transversely injected into laminar and turbulent flows has been characterized by measuring droplet position, shape and size as a function of time. From these measurements new information has been obtained on the effects of vaporization and unsteady curvilinear motion on droplet drag and lift in laminar flows. These measurements have also ... |
|
| The Effect of Turbulence on Vaporization and Mixing in Fuel Sprays |
08 FEB 95 |
9 pages |
| Authors:
Domenic A. Santavicca; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| An experimental study of droplet-turbulence interactions under simulated fuel spray conditions has been conducted. The behavior of individual droplets transversely injected into laminar and turbulent flows has been characterized by measuring droplet position, shape and size as a function of time. From these measurements new information has been obtained on the effects of vaporization and unsteady curvilinear motion on droplet drag and lift in laminar flows. These measurements have also ... |
|
| Experimental Research on Crossing Shock Wave Boundary Layer Interactions |
30 OCT 94 |
42 pages |
| Authors:
G. S. Settles; T. J. Garrison; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| An experimental research effort of the Penn State Gas Dynamics Laboratory on the subject of crossing shock wave boundary layer interactions is reported. This three year study was supported by AFOSR Grant 89-0315. A variety of experimental techniques were employed to study the above phenomena including planar laser scattering flowfield visualization, kerosene lampblack surface flow visualization, laser-interferometer skin friction surveys, wall static pressure measurements, and flowfield five-hole probe surveys. For ... |
|
| Surface Reactivity of Combustion Generated Soot Particles |
12 JUL 94 |
78 pages |
| Authors:
Robert J. Santoro; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| During the second year of this AASERT program, efforts have remained focused on the further development of the laser-induced incandescence technique and the sampling of soot particles from diffusion flames. Characterization of the laser-induced incandescence technique for soot particle measurements in laminar diffusion flames has been completed. In particular, the relationship between laser fluence and the temporal character of the laser-induced incandescence signal has been carefully examined and documented. Based ... |
|
| Detailed Studies of Soot Formation in Laminar Diffusion Flames for Application to Modeling Studies |
07 APR 94 |
96 pages |
| Authors:
Robert J. Santoro; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| An investigation of soot formation in laminar diffusion flames has shown that soot particle surface growth under laminar diffusion flame conditions ceases because of the depletion of hydrocarbon species, in particular acetylene and benzene, and not due soot particle reactivity loss due to thermal aging of the particles. This results has been obtained through direct species concentration measurements under well controlled conditions while the particle reactivity effects were calculated based ... |
|
| The Structure of High Reynolds Number Turbulent Boundary Layers, Part A |
15 FEB 94 |
17 pages |
| Authors:
James G. Brasseur; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| We provide a summary of our accomplishments under a three-year 'mini URI' program in collaboration with researchers at Yale and Princeton universities. Whereas the central theme of the program is high Reynolds number wall-bounded turbulence, studies at Penn State included (1) analysis of fundamental issues of scale interactions in high Reynolds number turbulence dynamics, (2) the use of the wavelet decomposition and generalized filtering techniques in describing the relationship between ... |
|
| Turbulence Structure Associated with Intercomponent and Interscale Energy Transfer and Modification by Forcing |
31 DEC 93 |
11 pages |
| Authors:
James G. Brasseur; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| There are two parts to this research program. First program focusses on the quantification of loosely held concepts such as 'structure,' and 'dynamic significance' of structure in the study of turbulent flows in general, and shear flows in particular. We have developed a robust algorithm which 'extracts' regions of concentrated activity in a fluctuating turbulence variable and labels each region individually for quantitative and graphical analysis, and applied the technique ... |
|
| Numerical Analysis of the Photo-Dissociation/Radical Oxidation of Formaldehyde by Ultraviolet Light in a Photolytic Reactor |
DEC 93 |
73 pages |
| Authors:
Robert O. Fetter; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| The release of volatile organic compounds (VOC's) into the atmosphere has come under fore by the Environmental Protection Agency (EPA) and state regulatory agencies in the past several years. These releases come from a wide variety of sources from gasoline filling stations to industrial and military operations. A new pollution control technology currently under development utilizes ultraviolet (UV) light to break down the volatile organic compounds (VOC's) contained in an ... |
|
| Acoustic Waves in Complicated Geometries and their Interactions with Liquid-Propellant Droplet Combustion |
14 MAY 93 |
145 pages |
| Authors:
Vigor Yang; M. W. Yoon; J. M. Wicker; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| A linear and nonlinear acoustic wave analysis has been developed for baffled combustion chambers. Results suggest three important effects of baffles on transverse modes of combustion instability. First, transverse waves can be longitudinalized inside baffle compartments. This may decouple combustion response from oscillatory motions if the processes near the injector face are sensitive to transverse variations in pressure. Second, severe restriction of the transverse component of acoustic velocity fluctuations is ... |
|
| Stability and Performance Robustness Assessment of Multivariable Control Systems |
APR 93 |
59 pages |
| Authors:
Asok Ray; Jenny H. Shen; Chen-Kuo Weng; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| This report presents the results of control systems analysis and their potential applications to control systems synthesis for high performance aircraft, and provides a proven, tractable and portable methodology to quantify the robust stability and performance of highly integrated digital fly-by-wire control systems. The H infinity-based mu-analysis approach has been recommended for quantitative evaluation of robust stability and performance of multi-input multi-output (MIMO) control systems. This approach for MIMO control ... |
|
| Detailed Studies of Soot Formation in Laminar Diffusion Flames for Application to Modeling Studies |
01 MAR 93 |
52 pages |
| Authors:
Robert J. Santoro; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| A study of soot particle formation in laminar diffusion flames has been undertaken to investigate soot precursor chemistry, particle inception and surface growth phenomena. During the first year of this study emphasis has been given to species concentrations measurements made using mass spectrometric techniques. These measurements have demonstrated that species measurements can be obtained in particle laden regions of diffusion flames using a novel sampling probe approach. In particular, measurements ... |
|
| Flame-Turbulence Interactions |
20 JAN 93 |
116 pages |
| Authors:
Domenic A. Santavicca; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| The interaction between individual vortices and a premixed laminar flame was investigated in order to characterize the underlying dynamics of flame-turbulence interactions and thereby gain an improved understanding of premixed turbulent flames. In addition, previous two-dimensional flame structure measurements made in turbulent premixed flames were re-analyzed in order to obtain flame curvature and orientation statistics.... Premixed Turbulent Flames, Flame-Vortex Interactions, Turbulence-Flame Interactions, Turbulent Flame Structure. |
|
| Soot Particle Inception and Growth Processes in Combustion |
APR 92 |
|
| Authors:
Robert J. Santoro; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| A study of soot particle inception and growth has been completed which considered fuel molecular structure, fuel concentration, temperature and operating pressure effects. These studies indicated that fuel species most strongly affected the particle inception process, as opposed to the surface growth process, and support an interpretation that inception controls the maximum amount of soot formed. Studies of concentration and temperature variations indicated that temperature effects dominate. The analysis yielded ... |
|
| Computational Modeling of Marine Propulsors |
31 MAR 92 |
|
| Authors:
PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| This letter represents our third quarterly progress report on the subject contract for the indicated period. In addition to planned objectives stated in our last quarterly report, namely, continued efforts on the 3-D parametric Navier Stokes study of the curved blade passage problem and further validation of our 3-D panel code for marine propellers with unsteady non-uniform inflow, our focus during this period included extensions of our Navier-Stokes code to ... |
|
| Study of Dynamic Behavior and Hazards of VHBR, LOVA, And PSS Propellants under Rapid Ignition And Combustion Conditions by Real-Time X-Ray Radiography |
09 DEC 91 |
166 pages |
| Authors:
K. K. Kuo; W. H. Hsieh; S. J. Ritchie; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| The purpose of this work is to study the dynamic behavior in the combustion of three types of propellants used in artillery systems. Theses propellants include very high burning rate (VHBR), low vulnerability ammunition (LOVA), and programmed splitting stick (PSS) propellants. Several advanced nonintrusive diagnostic instruments were utilized in this study. These instruments include: a real-time X-ray radiography system, a digital image processing system, a multi-channel laser doppler velocimeter, and ... |
|
| Coupling between Radiation and Gas Dynamics |
31 MAY 91 |
75 pages |
| Authors:
Charles L. Merkle; Michael M. Micci; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| Detailed experimental and analytic studies of microwave thermal propulsion are presented. Results are obtained for four geometric configurations: bluff-body stabilized resonant cavity plasmas; swirl-stabilized resonant cavity plasmas; free-floating plasmas in resonant cavities; and propagating, bluff-body stabilized plasmas in waveguides. Swirl stabilization proved to be less effective than bluff-body stabilization and was not modeled analytically. The experimental studies included both helium and nitrogen plasmas, while the analytic results are for helium ... |
|
| Soot Particle Inception and Growth Processes in Combustion |
APR 91 |
|
| Authors:
Robert J. Santoro; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| The present research program is intended to provide a fundamental understanding of the processes controlling soot particle formation under conditions applicable to future gas turbine engine operation. During the current year of the effort, work has emphasized the effects of concentration and temperature on the formation of soot particles. Through a carefully structured study, the effects of adding a diluent to the fuel stream of a diffusion flame have been ... |
|
| A Study of Gas Phase Chemistry of Solid Propellant Ingredients Using a CO2 Laser |
91 |
43 pages |
| Authors:
Thomas A. Litzinger; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| This research program was designed to address the critical need for data on the gas-phase chemistry of solid propellants through the development and application of a microprobe mass spectrometer (MPMS) system. The MPMS system was used to study the gas-phase chemical reactions occurring above solid propellant ingredients and actual solid propellants when they are heated and/or ignited by the heat flux from a CO2 laser. In addition to the MPMS ... |
|
| Fundamental Combustion Processes of Particle-Laden Shear Flows in Solid Fuel Ramjets |
17 MAY 90 |
429 pages |
| Authors:
K. K. Kuo; T. A. Litzinger; V. Yang; S. T. Thynell; W. H. Hsieh; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| Partial contents: Combustion of solid fuels under crossflow conditions; Carbon dioxide laser pyrolysis and ignition; Nonintrusive FT-IR diagnostics for species and temperature measurements of products from solid propellants; and Steady-state combustion behavior of MG/PTFE/VITON and boron- based solid fuels; Appendices include papers on: Ignition and combustion of solid fuels under high-velocity crossflows; Combustion characteristics and CO2 laser ignition behavior of boron/magnesium/PTFE pyrotechnics; Analysis of plumes of solid propellant combustion using ... |
|
| Fuel Structure and Pressure Effects on the Formation of Soot Particles in Diffusion Flames |
01 MAY 90 |
|
| Authors:
Robert J. Santoro; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| Studies emphasizing the effects of fuel concentration and operating pressure on the formation of soot particles have been conducted in a series of laminar diffusion flames. These experiments have shown that fuel concentration has a measurable effect on the amount of soot formed in the flame. However, a simple, constant proportionality between the fuel concentration and soot volume fraction has not been found to apply for the range of flow ... |
|
| Development of a Postprocessing and 3D Graphical Imaging Facility |
31 JAN 90 |
|
| Authors:
James G. Brasseur; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| This grant supported the acquisition of equipment towards the development of what has been termed a Postprocessing and 3D Graphical Imaging Facility. The primary function of the facility is in the analysis of numerical and experimental data, perhaps created in other laboratories, through the combination of quantitative and graphical tools. Specifically, the motivation is the analysis of Full Numerical Simulations of turbulent flows to study time- dependent three-dimensional structural characteristics ... |
|
| DURIP Optical Equipment for High-Speed Viscous-Inviscid Interaction Research |
05 JAN 90 |
|
| Authors:
Gary S. Settles; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| The Penn State Gas Dynamics Lab has an active, ongoing program in experimental high speed fluid dynamics research. The current research of the Laboratory, sponsored by AFOSR, ONR, and NASA, concerns supersonic viscous/ inviscid interactions, compressible turbulent mixing, and high-speed vortex dynamics pertaining to external and internal aerodynamics and propulsion. The Laboratory specializes in development and use of advanced, non-intrusive optical flow diagnostics in such research studies. These optical instruments ... |
|
| Experimental Research on Swept Shock Wave/Boundary Layer Interactions |
28 JUN 89 |
|
| Authors:
Gary S. Settles; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| An experimental research effort on the subject of swept shock wave interactions with turbulent boundary layers is reported. The research relied largely on non-intrusive, laser-based optical flow diagnostics. Experiments were carried out to define the Mach number influence, flowfield structure, and quantitative skin friction behavior of fin-generated swept interactions over the supersonic range from March 2.5 to 4.0, including weak, moderate, and strong interactions. The results of this research have ... |
|
| Coupling between Radiation and Gas Dynamics |
24 MAY 89 |
|
| Authors:
Charles L. Merkle; Michael M. Micci; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| Heat addition in flowing gases by electromagnetic wave absorption is being considered for propulsive purposes. The research includes both microwave and solar radiation. In the microwave studies, an experimental investigation of helium and nitrogen discharges has shown that free-floating plasmas can be established in either medium for a range of input powers and gas flow rates, although helium gives the broader range of stable limits. The discharges are being set ... |
|
| Analytical Study of Mistuning/Friction/Aerodynamics Interaction in a Bladed Disk Assembly |
06 FEB 89 |
80 pages |
| Authors:
Alok Sinha; Shing Chen; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| The analytical technique is shown to be valid for the computation of the statistics of blade's vibratory amplitude when the distributions of modal parameters of a mistuned bladed disk assembly are non-gaussian. The results from the analytical technique are compared with those from numerical simulations for triangular and uniform distributions. It was found that the probability density function of the amplitude is insensitive to the types of mistuning distributions. Next, ... |
|
| Automation and Optimization of the Design Parameters in Tactical Military Pipeline Systems |
DEC 88 |
|
| Authors:
Robert M. Frick; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| Tactical military petroleum pipeline systems will play a vital role in any future conflict due to an increased consumption of petroleum products by our combined Armed Forces. The tactical pipeline must be rapidly constructed and highly mobile to keep pace with the constantly changing battle zone. Currently, the design of these pipeline system is time consuming and inefficient, which may cause shortages of fuel and pipeline components at the front ... |
|
| Experimental Research on Swept Shock Wave/Boundary Layer Interactions |
28 APR 88 |
|
| Authors:
Gary S. Settles; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| This study of swept shock wave interactions with turbulent boundary layers relied entirely on non-intrusive, laser-based optical flow diagnostics. Experiments were carried out to define the flowfield structure of fin-generated interactions over a Mach number range 2.5 to 3.5 using the laser light-screen flow visualization technique. Further experiments resulted in accurate skin friction measurements in fin-generated swept interactions by way of the Laser Interferometer Skin Friction Meter. Techniques were perfected ... |
|
| Coupling between Radiation and Gas Dynamics |
01 MAR 88 |
|
| Authors:
Charles L. Merkle; Michael M. Micci; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| Direct heat addition of flowing gases by radiation absorption is considered. In the visible wavelength regime, the interaction between concentrated solar energy and a flowing gas is being modeled numerically. Additional analyses of laser-gasdynamic interactions are also being considered. Implicit time-iterative procedures originally developed for transonic flows are being adapted to the low Mach number, low Reynolds number regimes of interest. Two-dimensional solutions show that absorption plasmas can exist over ... |
|
| Fuel Structure and Pressure Effects on the Formation of Soot Particles in Diffusion Flames |
15 FEB 88 |
|
| Authors:
Robert J. Santoro; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| During the first year of the present grant, efforts have concentrated on examining the effects of fuel molecular structure on soot formation in diffusion flames. Studies involving alkane, alkene, alkyne and aromatic fuel species have been studied with specific attention given to the surface growth process. Analysis of these studies has demonstrated a strong fuel structure dependence for the amount of soot formed, the conversion percentage of fuel carbon to ... |
|
| Solar Rocket Plume/Mirror Interactions |
FEB 88 |
|
| Authors:
Charles L. Merkle; Sheng-Tao Yu; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| The extent to which the plume from a solar thermal rocket will impinge on the solar collector is studied by flowfield analysis. Such interaction can adversely affect collector performance through fouling, excessive heat loading, or pressure loads that deform the delicate structures. The geometrical shape of the collector is such that only the flow from the nozzle boundary layer can reach it, but the thrust levels of interest lead to ... |
|
| Premixed Turbulent Flame Propagation |
08 JAN 88 |
|
| Authors:
D. A. Santavicca; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| Results are presented from an experimental study of premixed turbulent flame propagation under atmospheric pressure, unconfined conditions. Stoichiometric propane air frames at two turbulence conditions were studied. LDV was used to obtain ensemble averaged measurements of velocity, turbulence intensity and integral time scale through the propagating flame. The integral length scale ahead of the flame was obtained both directly from a two-point spatial correlation measurement and indirectly using Taylor's hypothesis. ... |
|
Reports by Corporate Author
