NOTICE: The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Bruce Alberts is president of the National Academy of Sciences.
The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. William A. Wulf is president of the National Academy of Engineering.
The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an advisor to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Kenneth I. Shine is president of the Institute of Medicine.
The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy’s purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Bruce Alberts and Dr. William A. Wulf are chairman and vice chairman, respectively, of the National Research Council.
The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competencies and with regard for appropriate balance.
This report has been reviewed by a group other than the authors according to procedures approved by a Report Review Committee consisting of members of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine.
This study by the National Materials Advisory Board and the Board on Chemical Sciences and Technology was conducted under Federal Aviation Administration Research Grant No. 93-G-040 and Department of Defense Contract No. MDA972-92-C-0028.
Library of Congress Catalog Card Number 97-68118
International Standard Book Number 0-309-05833-3
Available in limited supply from:
National Materials Advisory Board
2101 Constitution Avenue, NW
HA-262
Washington, D.C. 20418
202-334-3505
Additional copies are available for sale from:
National Academy Press
2101 Constitution Avenue, NW Box 285 Washington, DC 20055 800-624-6242 or 202-334-3313 (in the Washington, D.C. metropolitan area)
Copyright 1997 by the National Academy of Sciences. All rights reserved.
Cover: Schlieren frames of Jet A under different air and fuel flow rate conditions. Source: Thor I. Eklund and Joseph C. Cox. 1978. Flame Propagation Through Sprays of Antimisting Fuels. NAFEC Technical Letter Report NA-78-66-LR. Atlantic City, N.J.: National Aviation Facilities Experimental Center.
Printed in the United States of America.
COMMITTEE ON AVIATION FUELS WITH IMPROVED FIRE SAFETY
JOHN J. WISE (chair),
Mobil Research and Development Corporation, Paulsboro, New Jersey
JAMES DAY,
Belcan Engineering Group, Inc., Cincinnati, Ohio
FREDERICK DRYER,
Princeton University, Princeton, New Jersey
PEYMAN GIVI,
State University of New York, Buffalo
RICHARD HALL,
Imbibitive Technologies, Midland, Michigan
SYED QUTUBUDDIN,
Case Western Reserve University, Cleveland, Ohio
ELIZABETH WECKMAN,
University of Waterloo, Waterloo, Ontario
Technical Consultant
THOR I. EKLUND,
Federal Aviation Administration (retired), Atlantic City, New Jersey
National Materials Advisory Board Liaison Representative
MICHAEL JAFFE,
Hoechst Celanese Research Division, Summit, New Jersey
National Materials Advisory Board Staff
THOMAS E. MUNNS, Senior Program Officer
JOHN A. HUGHES, Research Associate
BONNIE A. SCARBOROUGH, Research Associate
AIDA C. NEEL, Senior Project Assistant
NATIONAL MATERIALS ADVISORY BOARD
ROBERT A. LAUDISE (chair),
Lucent Technologies, Inc., Murray Hill, New Jersey
REZA ABBASCHIAN,
University of Florida, Gainesville
JAN D. ACHENBACH,
Northwestern University, Evanston, Illinois
MICHAEL I. BASKES,
Sandia-Livermore National Laboratory, Livermore, California
JESSE BEAUCHAMP,
California Institute of Technology, Pasadena
FRANCIS DISALVO,
Cornell University, Ithaca, New York
EDWARD C. DOWLING,
Cyprus AMAX Minerals Company, Englewood, Colorado
ANTHONY G. EVANS,
Harvard University, Cambridge, Massachusetts
JOHN A. S. GREEN,
The Aluminum Association, Washington, D.C.
JOHN H. HOPPS, JR.,
Morehouse College, Atlanta, Georgia
MICHAEL JAFFE,
Hoechst Celanese Research Division, Summit, New Jersey
SYLVIA M. JOHNSON,
SRI International, Menlo Park, California
LIONEL C. KIMERLING,
Massachusetts Institute of Technology, Cambridge
HARRY LIPSITT,
Wright State University, Dayton, Ohio
RICHARD S. MULLER,
University of California, Berkeley
ELSA REICHMANIS,
Lucent Technologies, Inc., Murray Hill, New Jersey
KENNETH L. REIFSNIDER,
Virginia Polytechnic University & State University, Blacksburg
EDGAR A. STARKE,
University of Virginia, Charlottesville
KATHLEEN C. TAYLOR,
General Motors Corporation, Warren, Michigan
JAMES WAGNER,
The Johns Hopkins University, Baltimore, Maryland
JOSEPH WIRTH,
Raychem Corporation (retired), Menlo Park, California
BILL G.W. YEE,
Pratt and Whitney, West Palm Beach, Florida
ROBERT E. SCHAFRIK, Director
BOARD ON CHEMICAL SCIENCES AND TECHNOLOGY
ROYCE W. MURRAY (co-chair),
University of North Carolina, Chapel Hill
JOHN J. WISE (co-chair),
Mobil Research and Development Corporation, Paulsboro, New Jersey
HANS C. ANDERSEN,
Stanford University, Stanford, California
JOHN L. ANDERSON,
Carnegie-Mellon University, Pittsburgh, Pennsylvania
DAVID C. BONNER,
Westlake Group, Houston, Texas
PHILIP H. BRODSKY,
Monsanto Company, Saint Louis, Missouri
MARVIN H. CARUTHERS,
University of Colorado, Boulder
GREGORY R. CHOPPIN,
Florida State University, Tallahassee
MOSTAFA EL-SAYED,
Georgia Institute of Technology, Atlanta
JOANNA S. FOWLER,
Brookhaven National Laboratory, Upton, New York
JUDITH C. GIORDAN,
ViE, Inc., Villanova, Pennsylvania
LOUIS C. GLASGOW,
E.I. duPont de Nemours and Company, Wilmington, Delaware
JOHN G. GORDON,
IBM, San Jose, California
ROBERT H. GRUBBS,
California Institute of Technology, Pasadena
VICTORIA F. HAYNES,
B.F. Goodrich Company, Brecksville, Ohio
GEORGE J. HIRASAKI,
Rice University, Houston, Texas
GARY E. MCGRAW,
Eastman Chemical Company, Kingsport, Tennessee
WAYNE H. PITCHER, JR.,
Genencor International, Inc., Palo Alto, California
GABOR A. SOMORJAI,
University of California, Berkeley
JOAN S. VALENTINE,
University of California, Los Angeles
WILLIAM J. WARD III,
General Electric, Schenectady, New York
DOUGLAS J. RABER, Director
Preface
Fire hazards associated with aircraft fuels have been a major concern of the military services, the Federal Aviation Administration, aircraft manufacturers, and aircraft operators. Current approaches to reduce the likelihood of fuel ignition emphasize design criteria for the routing of electrical wiring and fluid lines, fuel tank venting, engine fire walls, fire detection and suppression systems, and material fire resistance, as well as procedural rules regarding the storage, handling, and dispensing of fuel. However, as described in the 1996 National Research Council publication Fire-and Smoke-Resistant Interior Materials for Commercial Transport Aircraft: "Fuel flammability can overwhelm post-crash fire scenarios." Thus the reduction of the fire hazard of fuel is most critical for improving survivability for impact-survivable accidents.
The purpose of the Workshop on Aviation Fuels with Improved Fire Safety, held on November 19–20, 1996, at the National Research Council's Georgetown Facility, Washington, D.C., was to review the current state of development, technological needs, and promising technology for the future development of aviation fuels that are more resistant to ignition during a crash.
The organizing committee, which included recognized experts in aviation fuels, propulsion systems, combustion and flammability, additive materials, and analysis methods, developed the workshop format and agenda and identified potential participants. The committee felt that the most effective way to address this multidisciplinary topic was to include a series of invited presentations to provide background and perspective for workshop discussions and to introduce information on state-of-the-art technological developments. The invited speakers prepared summary papers, which are included in this proceedings (Parts II–IV). The workshop summary presented in Part I of this proceedings describes the subsequent workshop discussions and presents ideas for research and development that workshop participants felt were needed to develop fuels with improved fire safety.
This workshop provided a unique opportunity for participants representing a diverse range of technical backgrounds and experiences to get together to discuss a very difficult and important problem. The importance of the problem was impressed on the participants by a tragic accident that occurred at Baldwin Municipal Airport outside Quincy, Illinois, on the first evening of the meeting (November 19). The accident, as reported by the Chicago Tribune (November 20, 1996), involved a collision, on the ground, of a commuter aircraft with a private aircraft. The subsequent fuel fire, which resulted in 13 fatalities, was so intense that rescue personnel could not intervene.
This proceedings provides a summary of the results of the workshop and represents the views and opinions of the participants. The objective of the workshop was to identify technical issues and develop ideas for investigation and further development in an important area that has been essentially neglected for more than a decade. The committee hopes that the results of this effort catalyze further assessments by government and industrial organizations that will lead to real improvements in aviation fuel fire safety for both military and commercial operations.
Comments and suggestions can be sent via Internet electronic mail to nmab@nas.edu or by FAX to the NMAB (202) 334-3718.
JOHN J. WISE, CHAIR
COMMITTEE ON AVIATION FUELS WITH IMPROVED FIRE SAFETY
Acknowledgments
The committee on Aviation Fuels with improved fire safety acknowledges the hard work of the invited speakers, who prepared outstanding presentations that provided important background for workshop discussions and excellent papers for inclusion in this proceedings. The committee would also like to thank all of the workshop participants for contributing their time and energy to the workshop discussions.
The committee would also like to thank Douglas Mearns of the Naval Air Systems Command and Robert Morris of the Naval Research Laboratory for their help in planning the workshop. The committee is particularly grateful to Thor I. Eklund, whose vision helped to initiate this effort and whose perseverance and expertise helped to complete the proceedings.
Finally, the committee gratefully acknowledges the support of Thomas Munns, National Materials Advisory Board (NMAB) senior program officer, Aida C. Neel, NMAB senior project assistant, and Jack Hughes (until August, 1996) and Bonnie Scarborough, NMAB research associates.
Contents
|
||||
Federal Aviation Administration Research on Fuel Fire Safety |
||||
|
||||
Potential Surfactant Additives: The Search for the Oxymoron |
||||
Fire Safety in Military Aircraft Fuel Systems |
||||
Rheology: Tools and Methods |
||||
Jet Fuel Chemistry and Formulation |
||||
Concepts for Safe-Fuel Technology |
||||
|
||||
Engine Fuel System Design Issues |
||||
Applications of Vulnerability Analysis and Test Methods to Aircraft Design |
||||
Aircraft Fuel System Design Issues |
Figures and Tables
FIGURES
1-1 |
Controlled impact demonstration (CID) at Edwards Air Force Base, December 1984, |
|||
5-1 |
Availability of distillate fuels |
|||
5-2 |
Demand for kerosene jet fuel in the United States |
|||
5-3 |
The fire pyramid |
|||
5-4 |
Autoignition temperature (AIT) and flash point temperature measurement apparatus |
|||
5-5 |
Flammable liquids classification from the National Fire Protection Association (NFPA) and Hazardous Substances Act as related to flash point |
|||
5-6 |
Rate of flammability volume buildup |
|||
5-7 |
Flammable zone between leaking fuel-rich vapors and ambient air |
|||
5-8 |
Flammable regions for JP-4 |
|||
5-9 |
Flame spread across a jet fuel spill |
|||
5-10 |
Fire problem associated with projectiles piercing the fuel tank |
|||
6-1 |
Rod climbing (Weissenberg effect) |
|||
6-2 |
Tubeless siphon |
|||
6-3 |
Two types of shear deformation |
|||
6-4 |
Examples of material behavior under steady shear (flow curves) |
|||
6-5 |
Maxwell model for a viscoelastic material |
|||
6-6 |
Dynamic rheology and microstructure of colloidal dispersions |
|||
6-7 |
Dynamic mechanical spectrum (G´ and G´´ as functions of frequency ∞) for a typical polymer melt over a wide range of frequencies |
|||
6-8 |
A rheological experiment on a cone-and-plate geometry on a strain-controlled rotational rheometer |
|||
6-9 |
Uniaxial extensional flow on a cylindrical fluid element |
|||
6-10 |
Typical behavior of a polymer melt under steady shear and steady uniaxial extension |
|||
6-11 |
Steady shear viscosity (η) as a function of shear rate for two colloidal dispersions |
|||
6-12 |
Elastic (G´) and viscous (G´´) moduli as a function of frequency for the fumed-silica dispersions shown in Figure 6-11 |
|||
6-13 |
Steady shear viscosity (η) as a function of shear stress for aqueous solutions of an associative polymer |
|||
6-14 |
Elastic (G´) and viscous (G´´) moduli as a function of frequency for two associative polymer solutions |
|||
7-1 |
Two examples of chemical processing sequences used to produce jet fuel blend stocks |
|||
7-2 |
Two examples of catalytic treatments in the presence of hydrogen used to manufacture jet fuel bland stocks |
|||
7-3 |
Typical aviation fuel distribution system |
|||
9-1 |
Fuel system design for military aircraft: schematic drawing of the engine hydromechanical control system |
|||
9-2 |
Fuel system design for commercial aircraft: schematic drawing of PW 4084 fuel distribution system |
|||
10-1 |
Fire and explosion elements |
|||
10-2 |
Trade-off study approach |
11-1 |
Airplane fuel system, general arrangement |
|||
11-2 |
Engine and APU fuel feed system |
|||
11-3 |
A shrouded fuel line in a pressurized compartment |
|||
11-4 |
Typical installation of a fuel tank vent system |
|||
12-1 |
Measured and predicted structure of a laminar liquid-fueled diffusion flame |
|||
12-2 |
Measured universal state relationship for carbon dioxide species concentrations in laminar hydrocarbon-fueled diffusion flames |
|||
12-3 |
Measured mean mixture fraction distributions for round buoyant turbulent plumes plotted in terms of self-preserving variables |
|||
12-4 |
Measured and predicted profiles of mean streamwise velocities for self-preserving round buoyant turbulent plumes |
|||
12-5 |
Measured turbulent Prandtl/Schmidt numbers for self-preserving round buoyant turbulent plumes |
|||
12-6 |
Measured and predicted trajectory of the center-line of a plume for a round 204 MW fire source in a 4 m/s cross-flow with a -9.2 K/km lapse rate |
|||
12-7 |
Measured and predicted properties of a round buoyant turbulent acetylene/air diffusion flame |
|||
12-8 |
Measured and predicted temperatures for a rectangular liquid pool fire burning in air within an enclosure |
|||
12-9 |
Measured and predicted spectral radiation intensities for horizontal paths through the axis of acetylene-fueled round buoyant turbulent diffusion flames burning in air |
|||
12-10 |
Predicted state relationships for major gas species for an n-pentane spray burning in air at atmospheric pressure |
|||
12-11 |
Measured SMD after turbulent primary breakup of round liquid jets in still air with fully developed turbulent pipe flow at the jet exit |
|||
12-12 |
Measured and predicted mean and fluctuating particle properties in a round turbulent particle/air jet in still air at NTP |
|||
13-1 |
Basic configuration for flame spread above a liquid pool |
|||
13-2 |
Effect of initial fuel temperature (T0) on spread rate and domain size (δflow) for liquid motion |
|||
13-3 |
Pulsation cycle for flame spread above liquid fuel at low initial temperatures (T0) |
|||
13-4 |
Schematic diagram of the flow field approximations used around a hot projectile ignition |
|||
13-5 |
Variation along the limit of the relative velocity of the hot projectile with projectile temperature (TW) and projectile characteristics (L or R) or near wake length (L´) |
|||
13-6 |
Ignition time delay versus equivalence ratio (normalized mixture ratio) and initial droplet radius |
|||
13-7 |
Ignition time delay and ignition energy (Qig) versus distance from a hot wall |
|||
13-8 |
Ignition delay versus equivalence ratio for a polydisperse spray |
|||
13-9 |
Fuel vapor mass fraction versus axial position at various times |
|||
13-10 |
Gas temperature versus axial position at various times |
|||
14-1 |
Dual role of fuel dispersal from a process perspective |
|||
14-2 |
Processes involved in aircraft crashes as a function of time |
|||
14-3 |
Classification of crashes by impact velocity |
|||
14-4 |
Stages of pre-ignition fuel dispersal in the medium-impact velocity regime |
|||
14-5 |
Stages of post-ignition fuel dispersal in the medium-impact velocity regime |
|||
14-6 |
Transition from medium-to high-impact velocity regimes |
|||
14-7 |
Stages of fuel dispersal in the high-impact velocity regime |
|||
14-8 |
Example of numerical simulation tool for the impact stage of dispersal |
|||
14-9 |
Example of impact facility for studying the impact stage showing liquid impact into soil to determine dispersal |
14-10 |
Example of a numerical simulation tool for the study of the interphase momentum exchange stage using a modified version of the KIVA-II code, |
|||
14-11 |
Example of impact facility for studying the impact stage showing liquid impact into a runway, |
|||
B-1 |
Hypothetical structure of an ''association" polymer, |
|||
B-2 |
Micro-emulsion system water/K oleate/1-hexanol/hexdecane. S/CS ratio: 3/5, |
|||
B-3 |
Effect of temperature, |
|||
B-4 |
Ternary water-alcohol-hydrocarbon solutions, |
|||
B-5 |
Plan for "new" fire-resistant fuel (FRF), |
TABLES
5-1 |
Comparison of the Properties of Aviation Fuels, |
|||
5-2 |
Characteristics of Current Military Fuel Additives, |
|||
5-3 |
Flammability Properties of Aircraft Fluids, |
|||
5-4 |
Fire Prevention, Fire Detection, and Fire Control Techniques (MIL-F-87168), |
|||
5-5 |
Effects of Fuel Properties on Aircraft Performance and Fire Safety, |
|||
7-1 |
Examples of Some Jet Fuel Specifications, |
|||
7-2 |
Variations in Kerosene Hydrocarbon Compounds, |
|||
10-1 |
Ignition Sources from Ballistic Threats, |
|||
10-2 |
Ignition Sources from Mechanical Failures, |
|||
10-3 |
Location of Flammable Materials, |
|||
10-4 |
Damage Modes and Effects, |
|||
10-5 |
Factors That Alter the Probability of Fires and Explosions, |
|||
10-6 |
Hardening Approaches to Reducing Fires, |
|||
10-7 |
Hardening Approaches to Reducing Explosions, |
|||
B-1 |
Reference Fuel Properties, |
|||
B-2 |
Plan for "New" Fire-Resistant Fuel (FRF), |