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1998

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Articles 211 - 240 of 1354

Full-Text Articles in Engineering

Truck Route Access Evaluation: Madison County Industrial Park, Off Us 25 South Of Richmond, Site #2678, Lisa Aultman-Hall, Kenneth R. Agent, Brian Aldridge, David Cain, Nicole Lefever, Nikiforos Stamatiadis, Joel M. Weber Sep 1998

Truck Route Access Evaluation: Madison County Industrial Park, Off Us 25 South Of Richmond, Site #2678, Lisa Aultman-Hall, Kenneth R. Agent, Brian Aldridge, David Cain, Nicole Lefever, Nikiforos Stamatiadis, Joel M. Weber

Kentucky Transportation Center Research Report

There are two main objectives of the Freight Movement and Intermodal Access in Kentucky Study (SPR 98-189) undertaken by the Kentucky Transportation Center for the Kentucky Transportation Cabinet: evaluation of the access for trucks between intermodal or other truck generating sites and the National Highway System (NHS); and furthering the understanding of freight commodity flows throughout the state. This report summarizes the access evaluation for one cluster of facilities located in Madison county in the Bluegrass Area Development District (ADD) and KYTC Highway District #7. The location of the site is shown in Figure 1. Work on other specific sites …


An Integer Program Decomposition Approach To Combat Planning, John C. Van Hove Sep 1998

An Integer Program Decomposition Approach To Combat Planning, John C. Van Hove

Theses and Dissertations

Over the last two decades, our military forces have been working to incorporate the latest computer technology into the combat planning process. The earliest efforts use word processors, spreadsheets, and databases to organize planning data and to display high level summaries for commanders. Later efforts perform feasibility checks as missions are planned to insure that the necessary resources are available and that the assets requested are capable of meeting the assigned scheduling requirements. Some of the most recent computer planning tools have included the capability to automatically plan individual missions or groups of missions. These automated efforts have been heuristic …


Analysis Of Usaf Medium And Heavylift Space Launch Mission Reliability Requirements, Arthur R. Dawkins Sep 1998

Analysis Of Usaf Medium And Heavylift Space Launch Mission Reliability Requirements, Arthur R. Dawkins

Theses and Dissertations

The launch services that the USAF procures to carry DOD payloads into orbit are characterized by high risks and high costs. If a launch vehicle experiences a catastrophic failure, the cost of the entire launch vehicle, the launch processing, and the payload are completely lost (often in excess of 1,5 billion dollars.) Despite this enormous risk for the payload customer, and indeed the launch provider, launch success rates around the world are not much above 90 percent. The current USAF medium and heavylift launch systems are often based on technology that is 20 years old and older. Furthermore, little historical …


The Effects Of Three Media Presentation Systems On Maintenance Task Performance, John W. Chastain Sep 1998

The Effects Of Three Media Presentation Systems On Maintenance Task Performance, John W. Chastain

Theses and Dissertations

Wearable computers and Portable Maintenance Aids (PMAs) may soon be the normal way of doing aircraft maintenance in the Air Force. Currently, the Air Force uses the paper form of Technical Orders (TO's) while doing aircraft maintenance. The purpose of this thesis was to compare the effects of three different media presentations of the information used during aircraft maintenance. The three different presentations compared are the current paper form, a Head Mounted Display (HMD), and an auditory mode. An experiment was conducted to determine if there was a significant difference between the systems (in terms of task completion times and …


Electro-Mechanical Fatigue Behavior Of A Quasi-Isotropic Laminate With An Embedded Piezoelectric Actuator, Tse Lin Hsu Sep 1998

Electro-Mechanical Fatigue Behavior Of A Quasi-Isotropic Laminate With An Embedded Piezoelectric Actuator, Tse Lin Hsu

Theses and Dissertations

This study primarily investigated the electro-mechanical fatigue behavior of the embedded piezoelectric actuators in graphite/epoxy laminate with a lay-up of 0 | ± 45 | 90s. A secondary focus was the investigation of the mechanical fatigue effects of the 0 | 0 | ± 45 | 0 | 0 | 90s laminate with embedded PZT under tensile loading. All the fatigue tests were conducted with a triangular loading waveform which had a frequency of 10 Hz and with R=0. 1. In the electro-mechanical testing, the embedded actuator was excited by a -10 V to -100 V or a 10 V …


An Examination Of The United States Air Service's Logistics Operations, Andrew W. Hunt Sep 1998

An Examination Of The United States Air Service's Logistics Operations, Andrew W. Hunt

Theses and Dissertations

This historical study details the U.S. Air Service's logistics operations at home and abroad in an attempt to determine the relationship between the process and more recently established logistic principles. The information in the study was collected through an extensive review of both first hand accounts and historical compilations of the nature of World War I aviation logistics. Information regarding the production of the De Haviland DH-4 and Liberty Engine serve as the primary case examples of the operation of the logistics system. The established principles required for comparison were extracted from the writings of a number of expert military …


Data Storage Devices For Air Force Space Command: A Comparative Analysis, Darryl E. Mosley Sep 1998

Data Storage Devices For Air Force Space Command: A Comparative Analysis, Darryl E. Mosley

Theses and Dissertations

Two of Air Force Space Command's primary missions are ballistic missile warning and global navigation, accomplished by commanding and controlling Defense Support Program and Global Positioning System satellites respectively. The computerized ground control system, called the satellite command and control system (CCS) used to perform command and control of the satellites currently uses antiquated peripheral storage devices. These storage devices are critical components, but are often prone to failure, possibly resulting in adverse mission impact. The Air Force must choose an alternative storage device for use in conjunction with CCS in order to accommodate planned operations tempo increases. This thesis …


A Comparison Of 8-Hour Vs. 12-Hour Shifts On Performance, Health And Safety In A Usaf Aircraft Maintenance Squadron, Kelly J. Scott Sep 1998

A Comparison Of 8-Hour Vs. 12-Hour Shifts On Performance, Health And Safety In A Usaf Aircraft Maintenance Squadron, Kelly J. Scott

Theses and Dissertations

This study examined the effects of converting a large USAF aircraft maintenance squadron from an 8- hour shift system to a 12-hour shift system. In 1996, the squadron converted its 24-hour operations from three 8-hour work shifts, to two 12-hour work shifts with compressed work weeks. The squadron maintained 12-hour shifts for 19 consecutive months. A comparison was made of organizational performance, worker health and safety measures before, during and after 12-hour shift implementation. Findings indicated that changing from 8- to 12-hour shifts resulted in a slight increase in aircraft Mission Capability rates. However, this benefit appears to have come …


Value Of Increased Use Of Scheduled Maintenance On Aircraft Availability And Maintenance Cost Of The C-5, William T. Webb Sep 1998

Value Of Increased Use Of Scheduled Maintenance On Aircraft Availability And Maintenance Cost Of The C-5, William T. Webb

Theses and Dissertations

The C-5 consistently performs below its established mission capable rate of 75 percent. The purpose of this study was to investigate whether or not mission capable rates and maintenance costs can be improved by increased use of scheduled maintenance. Nine C-5 components were studied. Availability and cost were compared when scheduled replacement occurred at ten, twenty, and thirty percent before their respective mean time between failure and actual failure times. Actual failure times were not available so they were generated using simulation. The trade-off of using preventive maintenance is the decreased cost of sending fewer maintenance repair teams and increased …


Truck Route Access Evaluation: Bells Lane Cluster, Louisville, Site #7, Joel M. Weber, Kenneth R. Agent, Brian Aldridge, Lisa Aultman-Hall, David Cain, Nicole Lefever, Nikiforos Stamatiadis Sep 1998

Truck Route Access Evaluation: Bells Lane Cluster, Louisville, Site #7, Joel M. Weber, Kenneth R. Agent, Brian Aldridge, Lisa Aultman-Hall, David Cain, Nicole Lefever, Nikiforos Stamatiadis

Kentucky Transportation Center Research Report

This is a study undertaken on behalf of the Kentucky Transportation Cabinet (KYTC). There are two main objectives of the Freight Movement and Intermodal Access in Kentucky Study (SPR 98-189): evaluation of the access for trucks between intermodal or other truck generating sites and the National Highway System (NHS); and furthering the understanding of freight commodity flows throughout the state. This report summarizes the access evaluation for a cluster of facilities located along Bells Lane and Algonquin Parkway in Louisville in the KIPDA Area Development District (ADD) and KYTC Highway District #5. The location of the site is shown in …


Truck Route Access Evaluation: Campground Road Cluster, Louisville, Site #8, Joel M. Weber, Kenneth R. Agent, Brian Aldridge, Lisa Aultman-Hall, David Cain, Nicole Lefever, Nikiforos Stamatiadis Sep 1998

Truck Route Access Evaluation: Campground Road Cluster, Louisville, Site #8, Joel M. Weber, Kenneth R. Agent, Brian Aldridge, Lisa Aultman-Hall, David Cain, Nicole Lefever, Nikiforos Stamatiadis

Kentucky Transportation Center Research Report

This is a study undertaken on behalf of the Kentucky Transportation Cabinet (KYTC). There are two main objectives of the Freight Movement and Intermodal Access in Kentucky Study (SPR 98-189): evaluation of the access for trucks between intermodal or other truck generating sites and the National Highway System (NHS); and furthering the understanding of freight commodity flows throughout the state. This report summarizes the access evaluation for a cluster of facilities located along Campground Road in Louisville in the KIPDA Area Development District (ADD) and KYTC Highway District #5. The location of the site is shown in Figure 1. Work …


Truck Route Access Evaluation: Cook Family Foods, Grayson, Site #2663, Joel M. Weber, Kenneth R. Agent, Brian Aldridge, Lisa Aultman-Hall, David Cain, Nicole Lefever, Nikiforos Stamatiadis Sep 1998

Truck Route Access Evaluation: Cook Family Foods, Grayson, Site #2663, Joel M. Weber, Kenneth R. Agent, Brian Aldridge, Lisa Aultman-Hall, David Cain, Nicole Lefever, Nikiforos Stamatiadis

Kentucky Transportation Center Research Report

This is a study undertaken on behalf of the Kentucky Transportation Cabinet (KYTC). There are two main objectives of the Freight Movement and Intermodal Access in Kentucky Study (SPR 98-189): evaluation of the access for trucks between intermodal or other truck generating sites and the National Highway System (NHS); and furthering the understanding of freight commodity flows throughout the state. This report summarizes the access evaluation for the Cook Family Foods facility located in Carter county in the FIVCO Area Development District (ADD) and KYTC Highway District #9. The location of the site is shown in Figure 1. Work on …


Truck Route Access Evaluation: Central Kentucky Asphalt, Off Of Ky 1723, Site #2634, Brian Aldridge, Kenneth R. Agent, Lisa Aultman-Hall, David Cain, Nicole Lefever, Nikiforos Stamatiadis, Joel M. Weber Sep 1998

Truck Route Access Evaluation: Central Kentucky Asphalt, Off Of Ky 1723, Site #2634, Brian Aldridge, Kenneth R. Agent, Lisa Aultman-Hall, David Cain, Nicole Lefever, Nikiforos Stamatiadis, Joel M. Weber

Kentucky Transportation Center Research Report

The Freight Movement and Intermodal Access in Kentucky Study (SPR 98-189), undertaken by the Kentucky Transportation Center (KTC) on behalf of the Kentucky Transportation Cabinet (KYTC), has two main objectives. These objectives include 1) the evaluation of access for trucks between intermodal or other truck generating sites and the National Highway System (NHS) and 2) furthering the understanding of freight commodity flows throughout the state. This report summarizes the access evaluation for one facility located in Fayette County in the Bluegrass Area Development District (ADD) and KYTC Highway District #7. The location of the site is shown in Figure 1. …


Analysis Of Traffic Accident Data In Kentucky (1993 - 1997), Kenneth R. Agent, Jerry G. Pigman Sep 1998

Analysis Of Traffic Accident Data In Kentucky (1993 - 1997), Kenneth R. Agent, Jerry G. Pigman

Kentucky Transportation Center Research Report

This report includes an analysis of traffic accident data in Kentucky for the years of 1993 through 1997. A primary objective of this study was to determine average accident statistics for Kentucky highways. Average and critical numbers and rates of accidents were calculated for various types of highways in rural and urban areas. These data can be used in Kentucky's procedure to identify locations that have abnormal rates or numbers of accidents.

The other primary objective of this study was to provide data which can be used in the preparation of the problem identification portion of Kentucky's Annual Highway Safety …


Cost Estimating And Forecasting For Highway Work In Kentucky (Study Kyspr-94-158), James D. Stevens Sep 1998

Cost Estimating And Forecasting For Highway Work In Kentucky (Study Kyspr-94-158), James D. Stevens

Kentucky Transportation Center Research Report

Starting 1 July 1992, KRS45.245 granted the Interim Joint Committee on Transportation oversight of the biennial highway plan, including a review of all authorized highway project phases that exceed their estimates by 15%.

Estimates developed using current methods were not sufficiently accurate to preclude cost overruns in excess of 15%. Estimates were prepared before design began in order for the project to be included in the six-year plan. These estimates were not revised after a more detailed scope was available.

There were 562 overruns >15% at a cost of approximately $265 million during the period 7/1/92-7/1/98. All overruns were approved …


Truck Route Access Evaluation: Hopkinsville Industrial Park, Off Us 41 South Of Hopkinsville, Site #41, Kenneth R. Agent, Brian Aldridge, Lisa Aultman-Hall, David Cain, Nicole Lefever, Nikiforos Stamatiadis, Joel M. Weber Sep 1998

Truck Route Access Evaluation: Hopkinsville Industrial Park, Off Us 41 South Of Hopkinsville, Site #41, Kenneth R. Agent, Brian Aldridge, Lisa Aultman-Hall, David Cain, Nicole Lefever, Nikiforos Stamatiadis, Joel M. Weber

Kentucky Transportation Center Research Report

The Freight Movement and Intermodal Access in Kentucky Study (SPR 98-189) is being conducted on behalf of the Kentucky Transportation Cabinet (KYTC). There are two major objectives of the study: evaluation of the access for trucks between intermodal or other truck generating sites and the National Highway System (NHS); and furthering the understanding of freight commodity flows throughout the state. This report summarizes the access evaluation for one cluster of facilities located in Christian County in the Pennyrile Area Development District (ADD) and KYTC Highway District# 2. The location of the site is shown in Figure I. Work on other …


1998 Safety Belt Usage Survey And Evaluation Of Effectiveness In Kentucky, Kenneth R. Agent Sep 1998

1998 Safety Belt Usage Survey And Evaluation Of Effectiveness In Kentucky, Kenneth R. Agent

Kentucky Transportation Center Research Report

The objective of this study was to establish 1998 safety belt and child safety seat usage rates in Kentucky. The 1998 survey documents the continuing results from enacting a statewide mandatory safety belt law in 1994. Data were collected at 100 sites and combined based on vehicle miles travelled for a given type of highway, rural or urban location, and county population category. Also included in the report is an analysis of accident records evaluating the effectiveness of safety belts.

The data show that the usage rate has stabilized at a level slightly below the high value which occurred in …


Truck Route Access Evaluation: Paradise Power Plant, Muhlenberg County, Site #1113, Kenneth R. Agent, Brian Aldridge, Lisa Aultman-Hall, David Cain, Nicole Lefever, Nikiforos Stamatiadis, Joel M. Weber Sep 1998

Truck Route Access Evaluation: Paradise Power Plant, Muhlenberg County, Site #1113, Kenneth R. Agent, Brian Aldridge, Lisa Aultman-Hall, David Cain, Nicole Lefever, Nikiforos Stamatiadis, Joel M. Weber

Kentucky Transportation Center Research Report

The Freight Movement and Intermodal Access in Kentucky Study (SPR 98-189) is being conducted on behalf of the Kentucky Transportation Cabinet (KYTC). There are two major objectives of the study: evaluation of the access for trucks between intermodal or other truck generating sites and the National Highway System (NHS); and furthering the understanding of freight commodity flows throughout the state. This report summarizes the access evaluation for The Paradise Power Plant facility located in Muhlenberg County in the Pennyrile Area Development District (ADD) and KYTC Highway District # 2. The location of the site is shown in Figure 1. Work …


Response Of Runoff Diazinon Concentration To Formulation And Post-Application Irrigation, Joshua R. Evans, Dwayne R. Edwards, Stephen R. Workman, R. Michael Williams Sep 1998

Response Of Runoff Diazinon Concentration To Formulation And Post-Application Irrigation, Joshua R. Evans, Dwayne R. Edwards, Stephen R. Workman, R. Michael Williams

Biosystems and Agricultural Engineering Faculty Publications

Pesticides used in urban environments can be transported in runoff to downstream waters and cause adverse environmental consequences. This experiment assessed the effects of post-application irrigation depth (0, 6.4, and 12.7 mm) and formulation (liquid and granular) on concentration and transport of diazinon (a pesticide commonly used for lawn insect control) in runoff from “tall” fescue (Festuca arundinacea Schreb.) plots. The post-application irrigation was applied using rainfall simulators immediately following diazinon application. The rainfall simulators were again used approximately 2 h after diazinon application to apply the equivalent of a heavy rainfall (64 mm/h for approximately 1.5 h) to generate …


Entropy Generation In A Rectangular Packed Duct With Wall Heat Flux, Yaşar Demirel, Ramazan Kahraman Sep 1998

Entropy Generation In A Rectangular Packed Duct With Wall Heat Flux, Yaşar Demirel, Ramazan Kahraman

Papers in Thermal Mechanics

The entropy generation due to heat transfer and friction has been calculated for fully developed, forced convection flow in a large rectangular duct, packed with spherical particles, with constant heat fluxes applied to both the top (heated) and bottom (cooled) wall. An approximate analytical expression for the velocity profile developed for packed bed with H/dp > 5 has been used together with the energy equation of fully developed flow to calculate the non isothermal temperature profiles along the flow passage. The velocity profile takes into account the increase in the velocity near the wall due to the higher voidage in this …


Assessing And Updating Indot's Traffic Monitoring System For Highways, Volume 2 - Appendices B7 And C, Samuel Labi, Jon D. Fricker Sep 1998

Assessing And Updating Indot's Traffic Monitoring System For Highways, Volume 2 - Appendices B7 And C, Samuel Labi, Jon D. Fricker

JTRP Technical Reports

This study evaluates the existing resources and procedures ofINDOT's current traffic monitoring program, with the objective of transforming this program into a comprehensive Traffic Monitoring System for Highways (TMS/H). Reliable traffic data is a valuable input for studies and decision-making at various levels and in various phases of highway management including planning and design, finance and taxation, legislation and safety. The nature and scope of the various components comprising a TMS/H for any state were identified in available literature such as the Federal Register and Traffic Monitoring Guide.

A complete inventory of the existing resources (personnel and equipment) and procedures …


A Small/Micro-/Pico-Satellite Programfor Investigating Thunderstorm-Related Atmospheric Phenomena, Christopher Kitts Sep 1998

A Small/Micro-/Pico-Satellite Programfor Investigating Thunderstorm-Related Atmospheric Phenomena, Christopher Kitts

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Christopher Kitts titled "A Small/Micro-/Pico-Satellite Programfor Investigating Thunderstorm-Related Atmospheric Phenomena" from Septemebr of 1998.


Design Methodology For Low Speed High Altitude Long Endurance Unmanned Aerial Vehicles, Aaron Altman Sep 1998

Design Methodology For Low Speed High Altitude Long Endurance Unmanned Aerial Vehicles, Aaron Altman

Mechanical and Aerospace Engineering Faculty Publications

High Altitude Long Endurance (HALE) Unmanned Aerial Vehicles (UAV's) are increasingly being considered to perform a wide range of tasks. Recent years have seen greater value of UAV's in the military reconnaissance arena, first in the Persian Gulf war, with the use of small UAV's, and more recently over Bosnia with medium sized UAV's.

The NASA ERAST program uses HALE UAV's for environmental sensing and monitoring. The military has investigated using HALE UAV's for Theater Ballistic Missile defense, as well as general battlefield reconnaissance. Proposals have been made to use HALE UAV's for communications relay, long term surveillance (with a …


Magma Traps And Driving Pressure: Consequences For Pluton Shape And Emplacement In An Extensional Regime, John Patrick Hogan, Jonathan D. Price, M. Charles Gilbert Sep 1998

Magma Traps And Driving Pressure: Consequences For Pluton Shape And Emplacement In An Extensional Regime, John Patrick Hogan, Jonathan D. Price, M. Charles Gilbert

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The level of emplacement and final form of felsic and mafic igneous rocks of the Wichita Mountains Igneous Province, southwestern Oklahoma, U.S.A. Are discussed in light of magma driving pressure, lithostatic load, and crustal magma traps. Deposition of voluminous A-type rhyolites upon an eroded gabbroic substrate formed a subhorizontal strength anisotropy that acted as a crustal magma trap for subsequent rising felsic and mafic magma. Intruded along this crustal magma trap are the A-type sheet granites (length/thickness 100:1) of the Wichita Granite Group, of which the Mount Scott Granite sheet is typical, and smaller plutons of biotite bearing Roosevelt Gabbro. …


Bs News Sep 1998

Bs News

Building Services Engineering

No abstract provided.


Automatic Target Cueing Of Hyperspectral Image Data, Terry A. Wilson Sep 1998

Automatic Target Cueing Of Hyperspectral Image Data, Terry A. Wilson

Theses and Dissertations

Modern imaging sensors produce vast amounts data, overwhelming human analysts. One such sensor is the Airborne Visible and Infrared Imaging Spectrometer (AVIRIS) hyperspectral sensor. The AVIRIS sensor simultaneously collects data in 224 spectral bands that range from 0.4µm to 2.5µm in approximately 10nm increments, producing 224 images, each representing a single spectral band. Autonomous systems are required that can fuse "important" spectral bands and then classify regions of interest if all of this data is to be exploited. This dissertation presents a comprehensive solution that consists of a new physiologically motivated fusion algorithm and a novel Bayes optimal self-architecting classifier …


Feasibility Study On The Use Of The Internet For Traffic Of Unclassified Data, Alexandre L. Guerra, Luiz Gustavo F. P. Silva Sep 1998

Feasibility Study On The Use Of The Internet For Traffic Of Unclassified Data, Alexandre L. Guerra, Luiz Gustavo F. P. Silva

Theses and Dissertations

This research compares two possible networking methods for connecting all Brazilian Air Force Materiel Command units responsible for support and operation of Brazilian Air Force's weapons systems. The network includes the use of dedicated X.25 links, and the use of a virtual Private Network using the Internet (TCP/IP) as the medium of transmission. The Brazilian Air Force Materiel Command, responsible to support operating units over a very large sparse territory, lacks an efficient media of computer communications, which makes it difficult to control the supply chain channels of materiel present in each unit, depots, and warehouses. We studied the network …


Monotonic And Fatigue Behavior Of 2-D Woven Ceramic Matrix Composite At Room And Elevated Temperatures (Blackglas/Nextel 312), Musa Al-Hussein Sep 1998

Monotonic And Fatigue Behavior Of 2-D Woven Ceramic Matrix Composite At Room And Elevated Temperatures (Blackglas/Nextel 312), Musa Al-Hussein

Theses and Dissertations

This study investigated the monotonic tension and compression and the tension-tension and tension-compression fatigue loading of Blackglas/Nextel 312 woven CMC at room temperature and at 760 degrees centigrade. Young's Modulus and strain variation were evaluated. S-N curves were obtained for room and elevated temperatures. The ultimate tensile stress was lower at the elevated temperature and it was higher in the compression test. Failure-strain was higher at the elevated temperature in both tension and compression tests. There was no significant change in Young's Modulus at the elevated temperature. Also, there was no difference in the number of cycles to failure at …


Effects Of Shiftwork On Air Force Aircraft Maintenance Personnel, Craig A. Campbell Sep 1998

Effects Of Shiftwork On Air Force Aircraft Maintenance Personnel, Craig A. Campbell

Theses and Dissertations

This study examined the effects of converting a large aircraft maintenance squadron from 8-hour shifts to 12-hour shifts. The squadron studied converted its 24- hour maintenance work force from three 8-hour work shifts to two 12-hour work shifts incrementally, with one section converting to 12-hour shifts in January, 1996, and the remaining section converting in July, 1996. Both sections remained on 12-hour shifts until September, 1997, when both sections converted back to a three shift 8-hour operation. Health and well being, on- and off-duty accident rates, day shift vs. night shift accident rates, and the effects of stress and fatigue …


Use Of Polyurethane Material Models For Simulating Leg-Form Impact In Different Explicit Finite Element Codes, Joe Hassan, Peter Schuster, G. Frederick Sep 1998

Use Of Polyurethane Material Models For Simulating Leg-Form Impact In Different Explicit Finite Element Codes, Joe Hassan, Peter Schuster, G. Frederick

Mechanical Engineering

Compressible plastic foams are used throughout the interior and bumper systems of modern automobiles for safety enhancement and damage prevention. Consequently, modeling of foams has become very important for automobile engineers. To date, most work has focused on predicting foam performance up to approximately 80% compression. However, in certain cases, it is important to predict the foam under maximum compression, or 'bottoming-out.' This paper uses one such case-a thin low-density bumper foam impacted by a pedestrian leg-form at 11.1 m/s-to investigate the 'bottoming-out' phenomenon. Multiple material models in three different explicit Finite Element Method (FEM) packages (RADIOSS, FCRASH, and LS-DYNA) …