Scientific and Technical Aerospace Reports Volume 38 July 28, 2000

a unique spectroscopic signature of concerted intermolecular charge shifts. NBO analysis suggests how the nonlinear cooperativity
effects can be rationalized in terms of the fundamental n(sub N) yields sigma(sup *, sub CH) ”charge transfer” (”resonance”)
nature of H bonding, manifested even in low-polarity H bonds involving CH groups.
Author
Infrared Spectroscopy; Hydrocyanic Acid; Dielectric Properties; Structural Analysis
20000065620 NASA Marshall Space Flight Center, Huntsville, AL USA
Thermophysics Characterization of Kerosene Combustion
Wang, Ten-See, NASA Marshall Space Flight Center, USA; [2000]; 31p; In English; 34th; Thermophysics, 19-22 Jun. 2000, Denver,
CO, USA; Sponsored by American Inst. of Aeronautics and Astronautics, USA; Original contains color illustrations; Copyright
Waived; Avail: CASI; A03, Hardcopy; A01, Microfiche
A one-formula surrogate fuel formulation and its quasi-global combustion kinetics model are developed to support the design
of injectors and thrust chambers of kerosene-fueled rocket engines. This surrogate fuel model depicts a fuel blend that properly
represents the general physical and chemical properties of kerosene. The accompanying gaseous-phase thermodynamics of the
surrogate fuel is anchored with the heat of formation of kerosene and verified by comparing a series of one-dimensional rocket
thrust chamber calculations. The quasi-global combustion kinetics model consists of several global steps for parent fuel decomposition,
soot formation, and soot oxidation, and a detailed wet-CO mechanism. The final thermophysics formulations are incorporated
with a computational fluid dynamics model for prediction of the combustor efficiency of an uni-element, tri-propellant
combustor and the radiation of a kerosene-fueled thruster plume. The model predictions agreed reasonably well with those of the
tests.
Author
Combustion Physics; Computational Fluid Dynamics; Kerosene; Mathematical Models; Rocket Engine Design; Reaction Kinetics;
Thermodynamics
20000065632 NASA Marshall Space Flight Center, Huntsville, AL USA
Parallel Processing in Combustion Analysis
Schunk, Richard Gregory, NASA Marshall Space Flight Center, USA; Chung, T. J., Alabama Univ., USA; Apr. 26, 2000; 19p;
In English; Finite Elements in Flow Problems, 30 Apr. - 4 May 2000, Austin, TX, USA; No Copyright; Avail: CASI; A03, Hardcopy;
A01, Microfiche
The objective of this research is to demonstrate the application of the Flow-field Dependent Variation (FDV) method to a
problem of current interest in supersonic chemical combustion. Due in part to the stiffness of the chemical reactions, the solution
of such problems on unstructured three dimensional grids often dictates the use of parallel computers. Preliminary results for the
injection of a supersonic hydrogen stream into vitiated air are presented.
Derived from text
Flow Distribution; Parallel Processing (Computers); Supersonic Combustion; Parallel Computers
20000065650 Wisconsin Univ., Dept. of Chemistry, Madison, WI USA
Quadrupole Coupling Constants in Linear (HCN(n) Clusters: Theoretical and Experimental Evidence for Cooperativity
Effects in C-H...N Hydrogen Bonding
King, B. F., Wisconsin Univ., USA; Farrar, T. C., Wisconsin Univ., USA; Weinhold, F., Wisconsin Univ., USA; Journal of Chemical
Physics; Jul. 01, 1995; ISSN 0021-9606; Volume 103, No. 1, pp. 348-352; In English
Contract(s)/Grant(s): NSF CHE-90-07850; NSF CHE-91-02674; Copyright; Avail: Issuing Activity
Ab initio quadrupole coupling constants chi(D), chi(N-14) for deuterium and nitrogen nuclei are obtained for the sequence
of linear (HCN)(n) clusters (up to n=6) at the RHF/6-31 + G* level, complementing previous studies of n-dependent ”cooperative”
effects in these C-H ... N hydrogen-bonded species. For the dimer and trimer, the theoretical values are compared with experimental
equilibrium values of Gutowsky and co-workers and found to successfully reproduce both the magnitudes and patterns of measured
shifts. For larger (HCN)(n) clusters, the n-dependent trends in chi(D), chi(N-14) appear to be correlated with cooperativity
effects found previously (binding energies, geometrical parameters, dipole moments, ir frequencies and intensities). This suggests
that quadrupole coupling measurements can provide a useful probe of cooperative H-bonding phenomena in gaseous and condensed
media.
Author
Quadrupoles; Coupling; Constants; Molecular Clusters; Hydrocyanic Acid
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