A new molecular spectroscopic database for high-temperature modeling of the spectra of molecules in the gas phase is described. This database, called HITEMP, is analogous to the HITRAN database but encompasses many more bands and transitions than HITRAN for the absorbers H2O, CO2, CO, NO, and OH. HITEMP provides users with a powerful tool for a great many applications: astrophysics, planetary and stellar atmospheres, industrial processes, surveillance, non-local thermodynamic equilibrium problems, and investigating molecular interactions, to name a few. The sources and implementation of the spectroscopic parameters incorporated into HITEMP are discussed.

HITEMP, the high-temperature molecular spectroscopic database

Handbook of Numerical Heat Transfer Free Full Download Links from Multiple Mirrors added by DL4W on 2015-04-10 02:13:35. Handbook of heat transfer / editors, W.M. Rohsenow, J.P. Hartnett. Y.I. Cho. m 3rd ed. p. cm. Includes bibliographical references and index. ISBN 0-07053555-8. Students investigate heat transfer by conduction, convection and radiation. The analogy between heat and mass transfer is covered and applied in the analysis.

Handbook of heat transfer

We present the results of a new series of nongray calculations of the atmospheres, spectra, colors, and evolution of extrasolar giant planets (EGPs) and brown dwarfs for effective temperatures below 1300 K This theory encompasses most of the mass/age parameter space occupied by substellar objects and is the first spectral study down to 100 K These calculations are in aid of the multitude of searches being conducted or planned around the world for giant planets and brown dwarfs and reveal the exotic nature of the class Generically, absorption by H2 at longer wavelengths and H2O opacity windows at shorter wavelengths conspire to redistribute flux blueward Below 1200 K, methane is the dominant carbon bearing molecule and is a universal diagnostic feature of EGP and brown dwarf spectra We find that the primary bands in which to search are Z (~105 ?m), J (~12 ?m), H (~16 ?m), K (~22 ?m), M (~5 ?m), and N (~10 ?m), that enhancements of the emergent flux over blackbody values, in particular in the near infrared, can be by many orders of magnitude, and that the infrared colors of EGPs and brown dwarfs are much bluer than previously believed In particular, relative to J and H, the K band flux is reduced by CH4 and H2 absorption Furthermore, we conclude that for Teff's below 1200 K most or all true metals may be sequestered below the photosphere, that an interior radiative zone is a generic feature of substellar objects, and that clouds of H2O and NH3 are formed for Teff's below ~400 and ~200 K, respectively This study is done for solar-metallicity objects in isolation and does not include the effects of stellar insulation Nevertheless, it is a comprehensive attempt to bridge the gap between the planetary and stellar realms and to develop a nongray theory of objects from 03MJ (Saturn) to 70MJ (~007 M?) We find that the detection ranges for brown dwarf/EGP discovery of both ground- and space-based telescopes are larger than previously estimated

https://iopscience.iop.org/article/10.1086/305002/pdf

A Nongray Theory of Extrasolar Giant Planets and Brown Dwarfs

Turbulence, Coherent Structures, Dynamical Systems and SymmetryP. Holmes, J. L. Lumley, G. Berkooz, and C. W. Rowley, 2nd ed., Cambridge University Press, Cambridge, England, U.K., 2012, 386 pp., $90

Scalar profiles and NO formation in laminar opposed-flow partially premixed methane/air flames

Updated band model parameters for H2O, CO2, CH4 and CO radiation at high temperature

Different IR gas radiative property models suitable for a wide range of engineering applications (statistical narrowband, correlated- k :, correlated- k -fictitious gases, and models based on global absorption coefficient distribution functions, such as WSGG, SLW, ADF, and ADFFG) are presented. High-temperature properties, especially with CO 2 and H 2 O as active species, are emphasized. The accuracy of the different models is discussed by comparing their results with those of a line-by-line (LBL) approach, considered as a reference. This last model is introduced step by step, and the effects of the properties of the molecular states of the absorbing and emitting species on the properties of the corresponding spectra are discussed. The main physical features of complex IR spectra of CO 2 and H 2 O are presented in order to explain important phenomena occuring in different applications. The key point in the use of an LBL approach is the development of a complete and accurate spectroscopic database suitable for high-temperature applications. The parameters of approximate models are generated from the LBL approach in order to provide accurate predictions of radiative properties of uniform media. The intrinsic accuracy of these models applied to radiative transfer in nonuniform media is then studied. The implementation of the models is discussed on the basis of their formulations in terms of absorption coefficients or in terms of averaged transmissivities, and on the basis of their classification into band models and global models. Different methods for the treatment of mixtures of absorbing species are discussed.

Gas IR Radiative Properties: From Spectroscopic Data to Approximate Models

The absorption distribution function model with fictitious gases (ADFFG), a new global model of gas radiative properties, is presented and implemented for CO 2 and H 2 O radiation at atmospheric pressure and in the temperature range (300–2000 K). The model is based on the joint distribution function of the absorption coefficients of two fictitious gases corresponding to hot and cold lines of a given species. Model parameters are deduced from line-by-line (LBL) calculations founded on the EM2C spectroscopic databases. The accuracy of ADFFG is studied, for nonisothermal and nonhomogeneous columns representative of engineering applications, by comparisons with reference LBL calculations and results of the CK and CKFG narrow-band models. It is shown that the subdivision into two fictitious gases significantly enhances the accuracy of ADF (the same model without subdivision), in particular when gaseous absorption is significant, at the cost of larger computing times. Like all global models, ADFFG is, however, limited to applications where walls and particles are gray.

A fictitious-gas-based absorption distribution function global model for radiative transfer in hot gases

The accuracy of several narrow-band (SNB, CK, CKFG) and global (WSGG, SLW, ADF, ADFFG) gas infrared radiative property models applied to radiative transfer in a planar geometry with different types of temperature profiles is studied. The considered gaseous mixtures are H2ON2, CO2N2 and H2OCO2N2. Reference solutions are provided by line-by-line (LBL) calculations. All model parameters are based on the same spectroscopic data bases so that only the intrinsic accuracy of each model is tested. All narrow-band models lead in most cases to accurate results, but errors induced by the transmissivity-based models SNB and CKFG increase with wall reflectivity if the reflected radiation is assumed spectrally uncorrelated with gaseous transmissivity. Global models are less time consuming than narrow-band models but are generally less accurate and limited to media with gray boundaries and/or participating particles. The WSGG model leads in many cases to very important errors. The relative accuracy of the SLW and ADF models is typically about 10–20% but care must be taken in the choice of the reference temperature. The ADFFG model is the most accurate global model but requires greater computing times than the ADF and SLW models. For long range sensing of hot gases, only the fictitious-gas based models CKFG and ADFFG lead to accurate results. In the case of mixtures containing H2O and CO2, the spectral uncorrelation assumption is accurate for narrow-band models and its implementation results only in greater computing times for the CK model. On the contrary, this assumption is not generally accurate for the whole spectra and specific parameters must be generated from the joint distribution function of the absorption coefficients in the case of global models.

Accuracy of narrow-band and global models for radiative transfer in H2O, CO2, and H2OCO2 mixtures at high temperature

A previously presented line-by-line (LBL) calculation is used to test the validity of various approximate models. Narrow-band model parameters are generated from the lines used by the LBL approach in the 150–8000 cm -1 and 300–1500 K ranges. The accuracy of narrow-band models and of approximations for nonuniform paths applied to transmissivities and intensities of columns is studied. Random-statistical models give good results for the transmissivities but inaccurate results for the emitted intensities. Applications to combined conductive-radiative transfer in one-dimensional media are then presented. The temperature and flux distributions predicted by wide-band models are accurate when radiative transfer is preponderant; narrow-band models must be used in the case of optically thin media (e.g. in boundary layers).

Anouar Soufiani

Papers

Updated band model parameters for H2O, CO2, CH4 and CO radiation at high temperature

Gas IR Radiative Properties: From Spectroscopic Data to Approximate Models

A fictitious-gas-based absorption distribution function global model for radiative transfer in hot gases

Accuracy of narrow-band and global models for radiative transfer in H2O, CO2, and H2OCO2 mixtures at high temperature

Validity of band-model calculations for CO2 and H2O applied to radiative properties and conductive-radiative transfer