Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781723192067
Category :
Languages : en
Pages : 126
Book Description
The purpose of this research is to continue our efforts in advancing the state of knowledge in large eddy simulation (LES), direct numerical simulation (DNS), and Reynolds averaged Navier Stokes (RANS) methods for the computational analysis of high-speed reacting turbulent flows. In the second phase of this work, covering the period 1 Sep. 1993 - 1 Sep. 1994, we have focused our efforts on two research problems: (1) developments of 'algebraic' moment closures for statistical descriptions of nonpremixed reacting systems, and (2) assessments of the Dirichlet frequency in presumed scalar probability density function (PDF) methods in stochastic description of turbulent reacting flows. This report provides a complete description of our efforts during this past year as supported by the NASA Langley Research Center under Grant NAG1-1122. Givi, Peyman and Taulbee, Dale B. and Adumitroaie, Virgil and Sabini, George J. and Shieh, Geoffrey S. Unspecified Center COMPUTATIONAL FLUID DYNAMICS; PROBABILITY DENSITY FUNCTIONS; REACTING FLOW; STOCHASTIC PROCESSES; TURBULENT FLOW; DIRICHLET PROBLEM; HIGH SPEED; MIXING LAYERS (FLUIDS); NAVIER-STOKES EQUATION; VORTICES...
Les, DNS and Rans for the Analysis of High-Speed Turbulent Reacting Flows
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781723192067
Category :
Languages : en
Pages : 126
Book Description
The purpose of this research is to continue our efforts in advancing the state of knowledge in large eddy simulation (LES), direct numerical simulation (DNS), and Reynolds averaged Navier Stokes (RANS) methods for the computational analysis of high-speed reacting turbulent flows. In the second phase of this work, covering the period 1 Sep. 1993 - 1 Sep. 1994, we have focused our efforts on two research problems: (1) developments of 'algebraic' moment closures for statistical descriptions of nonpremixed reacting systems, and (2) assessments of the Dirichlet frequency in presumed scalar probability density function (PDF) methods in stochastic description of turbulent reacting flows. This report provides a complete description of our efforts during this past year as supported by the NASA Langley Research Center under Grant NAG1-1122. Givi, Peyman and Taulbee, Dale B. and Adumitroaie, Virgil and Sabini, George J. and Shieh, Geoffrey S. Unspecified Center COMPUTATIONAL FLUID DYNAMICS; PROBABILITY DENSITY FUNCTIONS; REACTING FLOW; STOCHASTIC PROCESSES; TURBULENT FLOW; DIRICHLET PROBLEM; HIGH SPEED; MIXING LAYERS (FLUIDS); NAVIER-STOKES EQUATION; VORTICES...
Publisher: Createspace Independent Publishing Platform
ISBN: 9781723192067
Category :
Languages : en
Pages : 126
Book Description
The purpose of this research is to continue our efforts in advancing the state of knowledge in large eddy simulation (LES), direct numerical simulation (DNS), and Reynolds averaged Navier Stokes (RANS) methods for the computational analysis of high-speed reacting turbulent flows. In the second phase of this work, covering the period 1 Sep. 1993 - 1 Sep. 1994, we have focused our efforts on two research problems: (1) developments of 'algebraic' moment closures for statistical descriptions of nonpremixed reacting systems, and (2) assessments of the Dirichlet frequency in presumed scalar probability density function (PDF) methods in stochastic description of turbulent reacting flows. This report provides a complete description of our efforts during this past year as supported by the NASA Langley Research Center under Grant NAG1-1122. Givi, Peyman and Taulbee, Dale B. and Adumitroaie, Virgil and Sabini, George J. and Shieh, Geoffrey S. Unspecified Center COMPUTATIONAL FLUID DYNAMICS; PROBABILITY DENSITY FUNCTIONS; REACTING FLOW; STOCHASTIC PROCESSES; TURBULENT FLOW; DIRICHLET PROBLEM; HIGH SPEED; MIXING LAYERS (FLUIDS); NAVIER-STOKES EQUATION; VORTICES...
LES, DNS and RANS for the Analysis of High-speed Turbulent Reacting Flows
Author:
Publisher:
ISBN:
Category : Eddies
Languages : en
Pages : 50
Book Description
"The purpose of this research is to continue our efforts in advancing the state of knowledge in large eddy simulation (LES), direct numerical simulation (DNS) and Reynolds averaged Navier Stokes (RANS) methods for the computational analysis of high-speed reacting turbulent flows. In the second phase of this work, covering the period: August 1, 1994 - August 1, 1995, we have focused our efforts on two programs: (1) Developments of explicit algebraic moment closures for statistical descriptions of compressible reacting flows, (2) Development of Monte Carlo numerical methods for LES of chemically reacting flows. This report provides a complete description of our efforts during this past year"--Abstract.
Publisher:
ISBN:
Category : Eddies
Languages : en
Pages : 50
Book Description
"The purpose of this research is to continue our efforts in advancing the state of knowledge in large eddy simulation (LES), direct numerical simulation (DNS) and Reynolds averaged Navier Stokes (RANS) methods for the computational analysis of high-speed reacting turbulent flows. In the second phase of this work, covering the period: August 1, 1994 - August 1, 1995, we have focused our efforts on two programs: (1) Developments of explicit algebraic moment closures for statistical descriptions of compressible reacting flows, (2) Development of Monte Carlo numerical methods for LES of chemically reacting flows. This report provides a complete description of our efforts during this past year"--Abstract.
Numerical Simulation of High-Speed Turbulent Reacting Flows
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781721931088
Category :
Languages : en
Pages : 208
Book Description
The objectives of this research are: (1) to develop and implement a new methodology for large eddy simulation of (LES) of high-speed reacting turbulent flows. (2) To develop algebraic turbulence closures for statistical description of chemically reacting turbulent flows. We have just completed the third year of Phase III of this research. This is the Final Report of our activities on this research sponsored by the NASA LaRC. Givi, P. and Taulbee, D. B. and Madnia, C. K. and Jaberi, F. A. and Colucci, P. J. and Gicquel, L. Y. M. and Adumitroaie, V. and James, S. Langley Research Center NAG1-1122
Publisher: Createspace Independent Publishing Platform
ISBN: 9781721931088
Category :
Languages : en
Pages : 208
Book Description
The objectives of this research are: (1) to develop and implement a new methodology for large eddy simulation of (LES) of high-speed reacting turbulent flows. (2) To develop algebraic turbulence closures for statistical description of chemically reacting turbulent flows. We have just completed the third year of Phase III of this research. This is the Final Report of our activities on this research sponsored by the NASA LaRC. Givi, P. and Taulbee, D. B. and Madnia, C. K. and Jaberi, F. A. and Colucci, P. J. and Gicquel, L. Y. M. and Adumitroaie, V. and James, S. Langley Research Center NAG1-1122
Large Eddy Simulations and Direct Numerical Simulations of High Speed Turbulent Reacting Flows
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781722333300
Category :
Languages : en
Pages : 28
Book Description
The main objective is to extend the boundaries within which large eddy simulations (LES) and direct numerical simulations (DNS) can be applied in computational analyses of high speed reacting flows. In the efforts related to LES, we were concerned with developing reliable subgrid closures for modeling of the fluctuation correlations of scalar quantities in reacting turbulent flows. In the work on DNS, we focused our attention to further investigation of the effects of exothermicity in compressible turbulent flows. In our previous work, in the first year of this research, we have considered only 'simple' flows. Currently, we are in the process of extending our analyses for the purpose of modeling more practical flows of current interest at LaRC. A summary of our accomplishments during the third six months of the research is presented. Givi, P. and Madnia, C. K. and Steinberger, C. J. and Frankel, S. H. and Vidoni, T. J. Unspecified Center NAG1-1122...
Publisher: Createspace Independent Publishing Platform
ISBN: 9781722333300
Category :
Languages : en
Pages : 28
Book Description
The main objective is to extend the boundaries within which large eddy simulations (LES) and direct numerical simulations (DNS) can be applied in computational analyses of high speed reacting flows. In the efforts related to LES, we were concerned with developing reliable subgrid closures for modeling of the fluctuation correlations of scalar quantities in reacting turbulent flows. In the work on DNS, we focused our attention to further investigation of the effects of exothermicity in compressible turbulent flows. In our previous work, in the first year of this research, we have considered only 'simple' flows. Currently, we are in the process of extending our analyses for the purpose of modeling more practical flows of current interest at LaRC. A summary of our accomplishments during the third six months of the research is presented. Givi, P. and Madnia, C. K. and Steinberger, C. J. and Frankel, S. H. and Vidoni, T. J. Unspecified Center NAG1-1122...
Large Eddy Simulation and Direct Numerical Simulation of High Speed Turbulent Reacting Flows
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781724273505
Category :
Languages : en
Pages : 232
Book Description
The objective of this research is to make use of Large Eddy Simulation (LES) and Direct Numerical Simulation (DNS) for the computational analyses of high speed reacting flows. Our efforts in the first phase of this research conducted within the past three years have been directed in several issues pertaining to intricate physics of turbulent reacting flows. In our previous 5 semi-annual reports submitted to NASA LaRC, as well as several technical papers in archival journals, the results of our investigations have been fully described. In this progress report which is different in format as compared to our previous documents, we focus only on the issue of LES. The reason for doing so is that LES is the primary issue of interest to our Technical Monitor and that our other findings were needed to support the activities conducted under this prime issue. The outcomes of our related investigations, nevertheless, are included in the appendices accompanying this report. The relevance of the materials in these appendices are, therefore, discussed only briefly within the body of the report. Here, results are presented of a priori and a posterior analyses for validity assessments of assumed Probability Density Function (PDF) methods as potential subgrid scale (SGS) closures for LES of turbulent reacting flows. Simple non-premixed reacting systems involving an isothermal reaction of the type A + B yields Products under both chemical equilibrium and non-equilibrium conditions are considered. A priori analyses are conducted of a homogeneous box flow, and a spatially developing planar mixing layer to investigate the performance of the Pearson Family of PDF's as SGS models. A posteriori analyses are conducted of the mixing layer using a hybrid one-equation Smagorinsky/PDF SGS closure. The Smagorinsky closure augmented by the solution of the subgrid turbulent kinetic energy (TKE) equation is employed to account for hydrodynamic fluctuations, and the PDF is employed for modeling the ...
Publisher: Createspace Independent Publishing Platform
ISBN: 9781724273505
Category :
Languages : en
Pages : 232
Book Description
The objective of this research is to make use of Large Eddy Simulation (LES) and Direct Numerical Simulation (DNS) for the computational analyses of high speed reacting flows. Our efforts in the first phase of this research conducted within the past three years have been directed in several issues pertaining to intricate physics of turbulent reacting flows. In our previous 5 semi-annual reports submitted to NASA LaRC, as well as several technical papers in archival journals, the results of our investigations have been fully described. In this progress report which is different in format as compared to our previous documents, we focus only on the issue of LES. The reason for doing so is that LES is the primary issue of interest to our Technical Monitor and that our other findings were needed to support the activities conducted under this prime issue. The outcomes of our related investigations, nevertheless, are included in the appendices accompanying this report. The relevance of the materials in these appendices are, therefore, discussed only briefly within the body of the report. Here, results are presented of a priori and a posterior analyses for validity assessments of assumed Probability Density Function (PDF) methods as potential subgrid scale (SGS) closures for LES of turbulent reacting flows. Simple non-premixed reacting systems involving an isothermal reaction of the type A + B yields Products under both chemical equilibrium and non-equilibrium conditions are considered. A priori analyses are conducted of a homogeneous box flow, and a spatially developing planar mixing layer to investigate the performance of the Pearson Family of PDF's as SGS models. A posteriori analyses are conducted of the mixing layer using a hybrid one-equation Smagorinsky/PDF SGS closure. The Smagorinsky closure augmented by the solution of the subgrid turbulent kinetic energy (TKE) equation is employed to account for hydrodynamic fluctuations, and the PDF is employed for modeling the ...
A Novel Strategy for Numerical Simulation of High-Speed Turbulent Reacting Flows
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781721606900
Category :
Languages : en
Pages : 36
Book Description
The objective of this research is to improve and implement the filtered mass density function (FDF) methodology for large eddy simulation (LES) of high-speed reacting turbulent flows. We have just completed Year 1 of this research. This is the Final Report on our activities during the period: January 1, 2003 to December 31, 2003. 2002. In the efforts during the past year, LES is conducted of the Sandia Flame D, which is a turbulent piloted nonpremixed methane jet flame. The subgrid scale (SGS) closure is based on the scalar filtered mass density function (SFMDF) methodology. The SFMDF is basically the mass weighted probability density function (PDF) of the SGS scalar quantities. For this flame (which exhibits little local extinction), a simple flamelet model is used to relate the instantaneous composition to the mixture fraction. The modelled SFMDF transport equation is solved by a hybrid finite-difference/Monte Carlo scheme. Sheikhi, M. R. H. and Drozda, T. G. and Givi, P. Langley Research Center
Publisher: Createspace Independent Publishing Platform
ISBN: 9781721606900
Category :
Languages : en
Pages : 36
Book Description
The objective of this research is to improve and implement the filtered mass density function (FDF) methodology for large eddy simulation (LES) of high-speed reacting turbulent flows. We have just completed Year 1 of this research. This is the Final Report on our activities during the period: January 1, 2003 to December 31, 2003. 2002. In the efforts during the past year, LES is conducted of the Sandia Flame D, which is a turbulent piloted nonpremixed methane jet flame. The subgrid scale (SGS) closure is based on the scalar filtered mass density function (SFMDF) methodology. The SFMDF is basically the mass weighted probability density function (PDF) of the SGS scalar quantities. For this flame (which exhibits little local extinction), a simple flamelet model is used to relate the instantaneous composition to the mixture fraction. The modelled SFMDF transport equation is solved by a hybrid finite-difference/Monte Carlo scheme. Sheikhi, M. R. H. and Drozda, T. G. and Givi, P. Langley Research Center
Monthly Catalog of United States Government Publications
Monthly Catalogue, United States Public Documents
Author:
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 950
Book Description
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 950
Book Description
Scientific and Technical Aerospace Reports
DNS and the LES Closure of Reacting Turbulence in Hypersonic Flows
Author: María del Pino Martín Aguirre
Publisher:
ISBN:
Category :
Languages : en
Pages : 216
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 216
Book Description