Scientific and Technical Aerospace Reports Volume 39 April 6, 2001

More documents

Recommendations

Info

20010022642 Stanford Univ., Center for Turbulence Research, Stanford, CA USA Doubly-Conditional Moment Closure Modeling of Turbulent Nonpremixed Combustion Cha, Chong M., Stanford Univ., USA; Kosaly, George, Washington Univ., USA; Pitsch, Heinz, Stanford Univ., USA; Annual Research Briefs - 2000: Center for Turbulence Research; December 2000, pp. 129-140; In English; See also 20010022631; No Copyright; Avail: CASI; A03, Hardcopy; A03, Microfiche The accurate treatment of extinction and reignition phenomena is thought to be an important factor in determining how flame stabilization occurs in practical, nonpremixed combustion systems. In the joint probability density function (PDF) approach, extinction/reignition can be treated with improved mixing models. However, joint PDF methods employ a Monte-Carlo type solution procedure and thus become computationally expensive when many species increase the dimensionality of the modeled joint PDF evolution equation. Presumed PDF approaches such as flamelet modeling and conditional moment closure modeling can be computationally tractable when many species are to be described, as is generally the case in problems of practical importance. First-order flamelet modeling and conditional moment closure modeling with singly-conditional, first-moment closure breaks down when extinction and/or reignition phenomena are present. The focus of the present paper concerns extensions of first-order conditional moment closure modeling to describe extinction/reignition. Currently, a fundamental closure approximation in singlyconditional moment closure modeling is first-order closure of the average nonlinear chemical source terms, w, conditioned on the mixture fraction, Xi(t, x) = eta: ,
ustion, showing that these can have a strong impact and can lead to local flame extinction, even if the conditional mean scalar dissipation rate is well below the extinction limit. In the present work the LFM will be extended to account for local inhomogeneities of the scalar dissipation rate. In the following sections, first the governing equations will be derived and the relation to the flamelet equations derived in earlier work by Peters will be discussed. Following this, the numerical implementation of the resulting equations will be described, and finally, numerical results from the LES of a turbulent jet diffusion flame will be discussed and compared to the results obtained from the LFM and to experimental data. Author Lagrangian Function; Large Eddy Simulation; Turbulent Combustion; Turbulent Flames 20010022811 Army Research Lab., Weapons and Materials Research Directorate, Aberdeen Proving Ground, MD USA Kinetics of the O(P-3) + N2O Reaction, 1, Direct Measurements at Intermediate Temperatures Final Report, Sep. 1995 - Dec. 1999 Fontijn, Arthur, Rensselaer Polytechnic Inst., USA; Goumri, Abdellatif, Rensselaer Polytechnic Inst., USA; Fernandez, Abel, Rensselaer Polytechnic Inst., USA; Anderson, William R., Army Research Lab., USA; Meagher, Nancy E., Army Research Lab., USA; Journal of Physical Chemistry A; 2000; Volume 104, No. 25, pp. 6003-6012; In English Contract(s)/Grant(s): DAAH04-95-1-0098; DAAG55-98-1-0183 Report No.(s): AD-A384812; ARL-RP-10; Copyright; Avail: Defense Technical Information Center (DTIC) Rate coefficients for the consumption of O atoms by their reaction with N2O have been measured, at pressures from 130 to 500 mbar, using the high-temperature photochemistry technique. These represent the first direct measurements of k values of the reaction. The ground-state oxygen atoms were produced by laser photolysis of SO2, or by flash photolysis either SO2 or O2, and monitored by time-resolved resonance fluorescence. The results yield k(1075-1140 K) = 3.2x10(exp -11) exp(-9686K/T) cubic cm/molecule/s with 2-sigma precision limits of +/- 12% corresponding 2-sigma accuracy limits of +/- 26%. Results from several sources in the literature indicate a high sensitivity of the O + N2O reaction system to traces of H2O, which increases the rates if present as a contaminant. For this reason, possible effects of traces of H2O on the results were modeled. Simulated decay curves with a hypothetical H2O contaminant were used as a test of the experimental data reduction procedures. Although the concentration of H2O needed to significantly affect the results is small, the amount that could have been present is even less and is shown to have had negligible effects. The results are in qualitative agreement with a recent Tis greater than or equal to 1680 K shock tube study in that extrapolation of their results to the present temperatures indicates rate coefficients much larger than had been previously thought. However, though results agree within error limits for such a long extrapolation the present results are about a factor of four smaller. Combined with the results of the companion paper by Meagher and Anderson, in which the prior literature is critically reevaluated, it is found that the O2 + N2 product channel dominates at the present temperature. Author Coefficients; Kinetics; Photochemical Reactions; Consumption 20010023792 Army Research Lab., Human Research and Engineering Directorate, Aberdeen Proving Ground, MD USA Transitioning Model Potentials to Real Systems. II. Application to Molecular Oxygen Bembenek, Scott D.; Rice, Betsy M.; Sep. 2000; 15p; In English; Pub in the Journal of Chemical Physics v113 n6 pp2354-2359, 8 August 2000. Prepared in collaboration with the Department of Chemistry, Colorado State University, Fort Collins, CO. Contract(s)/Grant(s): Proj-622618.H80 Report No.(s): AD-A385465; ARL-RP-13; No Copyright; Avail: CASI; A03, Hardcopy; A01, Microfiche Recently, we introduced a novel computer simulation technique to determine the optimal set of parameters of an interaction potential for a simple monatomic liquid. This technique was used to obtain interaction potentials of the Lennard-Jones form that accurately describe argon over its entire liquid phase at a fixed pressure (S. D. Bembenek and B. M. Rice, Mol. Phys. 97, 1085 1999). Here, we extend this technique to a homonuclear diatomic molecular system, liquid oxygen. This technique was first applied to a system in which the oxygen molecules were treated as point masses interacting through a modified Lennard-Jones potential. Simulations using the resulting optimal set of potential parameters of this system predict densities that are within 0.25% of experiment over the entire liquid range of oxygen at a fixed pressure. However, the errors in the internal energy and the enthalpy were as large as 9.8%. The technique was then used to determine the optimal parameters for a system of harmonic molecules, in which each molecule has two interaction sites centered at the atomic nuclei. The intermolecular interaction is the sum of all site-site interactions described by a modified Lennard-Jones potential. Simulations using these parameters reproduce experimental densities with an error no greater than 0.80%. The predictions of the internal energy and enthalpy differ from experiment by no more 25
Page 1 and 2: Scientific and Technical Aerospace
Page 3 and 4: Introduction Scientific and Technic
Page 5 and 6: Subject Divisions Table of Contents
Page 7 and 8: Subject Categories of the Division
Page 13 and 14: 73 Nuclear Physics 263 Includes nuc
Page 15 and 16: Document Availability Information T
Page 17 and 18: Avail: NASA Public Document Rooms.
Page 19 and 20: Hardcopy & Microfiche Prices Code N
Page 21 and 22: ALABAMA AUBURN UNIV. AT MONTGOMERY
Page 23 and 24: ��
Page 25 and 26: 03 AIR TRANSPORTATION AND SAFETY
Page 27 and 28: work of the JAA had established thi
Page 29 and 30: 20010024868 Federal Aviation Admini
Page 31 and 32: 20010023437 Defence Science and Tec
Page 33 and 34: The Models for Aeroelastic Validati
Page 35 and 36: 20010025824 Pratt and Whitney Aircr
Page 37 and 38: 20010023064 NASA Langley Research C
Page 39 and 40: 17 SPACE COMMUNICATIONS, SPACECRAFT
Page 41 and 42: 20010026207 NASA, Washington, DC US
Page 43 and 44: The objective of the proposed resea
Page 45: 20010022640 Stanford Univ., Center
Page 49 and 50: 20010026184 Oak Ridge National Lab.
Page 51 and 52: film. Subsequent electroless metal
Page 53 and 54: 20010024029 Houston Univ., Dept. of
Page 55 and 56: equipment indicate a change in the
Page 57 and 58: interaction, the main gas products
Page 59 and 60: Contract(s)/Grant(s): W-7405-eng-48
Page 61 and 62: for detecting and measuring deviato
Page 63 and 64: work, additional significant effect
Page 65 and 66: 20010026182 Oak Ridge National Lab.
Page 67 and 68: 20010024162 Army Research Lab., Ade
Page 69 and 70: matching funds. MIRSL purchased an
Page 71 and 72: 20010023557 North Dakota State Univ
Page 73 and 74: 20010026217 Princeton Univ., NJ USA
Page 75 and 76: 20010024108 Center for Naval Analys
Page 77 and 78: 20010022631 Stanford Univ., Center
Page 79 and 80: undertaken to isolated it are descr
Page 81 and 82: 20010022648 Stanford Univ., Center
Page 83 and 84: non-buoyant axisymmetric jet issuin
Page 85 and 86: point. The other turbulent problem
Page 87 and 88: 20010024042 Houston Univ., Dept. of
Page 89 and 90: The research carried out in the Hea
Page 91 and 92: along the heater surface and depart
Page 93 and 94: cal transducers. Additionally, the
Page 95 and 96: tial for its successful commercial
Page 97 and 98:
This project represents a combined
Page 99 and 100:
20010024910 Johns Hopkins Univ., De
Page 101 and 102:
e caused by a non-uniform temperatu
Page 103 and 104:
metric shear cell, employed upon th
Page 105 and 106:
20010024919 Alabama Univ., Huntsvil
Page 107 and 108:
Newtonian fluids in the laboratory,
Page 109 and 110:
Boussinesq convection where due to
Page 111 and 112:
20010024930 Creare, Inc., Hanover,
Page 113 and 114:
Illumination of a space-borne objec
Page 115 and 116:
The hydrodynamics near steadily mov
Page 117 and 118:
to be done is the full coupled syst
Page 119 and 120:
liquid crystal host. Since the ulti
Page 121 and 122:
the inorganic synthesis using press
Page 123 and 124:
when the buoyancy is removed, for e
Page 125 and 126:
20010024956 NASA Ames Research Cent
Page 127 and 128:
2.2-second drop tower at NASA Glenn
Page 129 and 130:
we have examined the dynamical beha
Page 131 and 132:
position of the interface. An oscil
Page 133 and 134:
the first time, non-intrusive, high
Page 135 and 136:
’axial curvature pressure’. A t
Page 137 and 138:
moons when disturbed by low velocit
Page 139 and 140:
particle size was studied. In a den
Page 141 and 142:
colliding drops. The viscous resist
Page 143 and 144:
20010024983 Notre Dame Univ., Physi
Page 145 and 146:
20010024986 TDA Research, Inc., Whe
Page 147 and 148:
drop deposition, using Schiaffino a
Page 149 and 150:
and extended to reduced gravity flo
Page 151 and 152:
from an isolated bubble regime to a
Page 153 and 154:
20010025000 Case Western Reserve Un
Page 155 and 156:
our experimental measurements and w
Page 157 and 158:
sured using a hot film probe flush
Page 159 and 160:
the stationary bubble entrains anot
Page 161 and 162:
we have collaborated on 3D experime
Page 163 and 164:
of the most attractive characterist
Page 165 and 166:
apply either steady shear flow perp
Page 167 and 168:
20010025024 NASA, Washington, DC US
Page 169 and 170:
neously the gamma scattered method
Page 171 and 172:
20010023125 Colorado Univ., Lab. fo
Page 173 and 174:
Contract(s)/Grant(s): F19628-95-C-0
Page 175 and 176:
ics Technology Letters; March 2000;
Page 177 and 178:
The BOREAS RSS-1 team collected sur
Page 179 and 180:
ically corrected; however, files of
Page 181 and 182:
with wavelength bands specific to t
Page 183 and 184:
20010022099 NASA Goddard Space Flig
Page 185 and 186:
within the polygon). There are thre
Page 187 and 188:
A03, Hardcopy; A01, Microfiche Cana
Page 189 and 190:
Page 191 and 192:
Page 193 and 194:
storms in Africa and smoke plumes f
Page 195 and 196:
Greenland, with the objective of qu
Page 197 and 198:
The BOReal Ecosystem-Atmosphere Stu
Page 199 and 200:
The BOREAS TGB-8 team collected dat
Page 201 and 202:
Page 203 and 204:
Report No.(s): NASA/TM-2000-209891/
Page 205 and 206:
Page 207 and 208:
The BOREAS TF-10 team collected tow
Page 209 and 210:
Page 211 and 212:
Page 213 and 214:
Page 215 and 216:
cally Active Radiation (FPAR) absor
Page 217 and 218:
tributing to the overall understand
Page 219 and 220:
cal ’tour de force’ allows EPV
Page 221 and 222:
20010023558 Texas Univ., Center for
Page 223 and 224:
the atmospheric concentrations of m
Page 225 and 226:
20010023278 Lembaga Penerbangan dan
Page 227 and 228:
Atmospheric radiation in the infrar
Page 229 and 230:
20010022976 Desert Research Inst.,
Page 231 and 232:
The primary purpose of AASERT Grant
Page 233 and 234:
with only small ice-covered areas r
Page 235 and 236:
Task 2 - abstraction of Medical rec
Page 237 and 238:
non-steroidal activators of the rec
Page 239 and 240:
20010023796 Massachusetts Univ. Med
Page 241 and 242:
20010024166 Chicago Univ., Chicago,
Page 243 and 244:
20010025069 Cleveland Clinic Founda
Page 245 and 246:
Prior to 1994, measurement of tumor
Page 247 and 248:
20010025730 Illinois Univ., Broad o
Page 249 and 250:
the processing for enhancement of s
Page 251 and 252:
strides in detection, diagnosis, an
Page 253 and 254:
20010025763 California Univ., Lawre
Page 255 and 256:
The ability to detect carcinoma cel
Page 257 and 258:
ations found in clinical and geneti
Page 259 and 260:
20010021850 Michigan Univ., Dept. o
Page 261 and 262:
20010021985 National Inst. of Healt
Page 263 and 264:
20010023264 Department of Health an
Page 265 and 266:
on the BBB in rats, researchers not
Page 267 and 268:
navigation method shows an advantag
Page 269 and 270:
ange, and for some combinations of
Page 271 and 272:
consider two specific issues in app
Page 273 and 274:
planning with the Remote Agent expe
Page 275 and 276:
training courses for the CAD tools.
Page 277 and 278:
In this report, we consider the pro
Page 279 and 280:
of the neural network and hence, th
Page 281 and 282:
65 STATISTICS AND PROBABILITY �
Page 283 and 284:
from the Lagrangian of the system.
Page 285 and 286:
The average U-235 neutron total cro
Page 287 and 288:
20010026201 Sandia National Labs.,
Page 289 and 290:
to be 8.5-10.5 degrees which concur
Page 291 and 292:
77 PHYSICS OF ELEMENTARY PARTICLES
Page 293 and 294:
20010026247 Abdus Salam Internation
Page 295 and 296:
Board (Access Board) under the auth
Page 297 and 298:
currently underway or planned durin
Page 299 and 300:
transfer function that would cover
Page 301 and 302:
90 ASTROPHYSICS ��
Page 303 and 304:
strates that as the gyroradius incr
Page 305 and 306:
20010023043 Jet Propulsion Lab., Ca
Page 307 and 308:
climatic variations. This can only
Page 309 and 310:
try), allowing the same samples, in
Page 311 and 312:
This work will describe the Thermal
Page 313 and 314:
20010023068 Tennessee Univ., Dept.
Page 315 and 316:
is crucial to the successful landin
Page 317 and 318:
flat-plate Michelson interferometer
Page 319 and 320:
general public is definitely intere
Page 321 and 322:
Page 323 and 324:
exploration, examine specific optio
Page 325 and 326:
tions of water. Often, due to lower
Page 327 and 328:
With the exploration strategy for M
Page 329 and 330:
necessary to ensure delivery of a s
Page 331 and 332:
Page 333 and 334:
spectral studies to the field, and
Page 335 and 336:
93 SPACE RADIATION ��
Page 337 and 338:
ATMOSPHERIC RADIATION, 163, 205 ATM
Page 339 and 340:
DEW POINT, 165 DIAGNOSIS, 217, 220,
Page 341 and 342:
GRAVITATION, 54, 84, 88, 110, 111,
Page 343 and 344:
MATRIX THEORY, 270 MEASURING INSTRU
Page 345 and 346:
ST-10 Q QUALITY CONTROL, 11, 213 QU
Page 347 and 348:
ST-12 T TARGET RECOGNITION, 265 TAS
Page 349 and 350:
A Abdelguerfi, Mahdi, 252 Abramo, R
Page 351 and 352:
Cledassou, R., 311 Clemmet, J., 306
Page 353 and 354:
Gorelick, N., 294 Gorevan, S. P., 4
Page 355 and 356:
Kupinski, Matthew A., 256 Kuznetz,
Page 357 and 358:
Parks, C. H., 249 Parr, T. P., 38 P
Page 359 and 360:
Swisdak, Michael M., Jr., 37 Szalew
show all

Scientific and Technical Aerospace Reports Volume 39 April 6, 2001

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?