Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781724264602
Category :
Languages : en
Pages : 30
Book Description
An extended kappa-epsilon turbulence model is proposed and tested with successful results. An improved transport equation for the rate of dissipation of the turbulent kinetic energy, epsilon, is proposed. The proposed model gives more effective response to the energy production rate than does the standard kappa-epsilon turbulence model. An extra time scale of the production range is included in the dissipation rate equation. This enables the present model to perform equally well for several turbulent flows with different characteristics, e.g., plane and axisymmetric jets, turbulent boundary layer flow, turbulent flow over a backward-facing step, and a confined turbulent swirling flow. A second-order accurate finite difference boundary layer code and a nearly second-order accurate finite difference elliptic flow solver are used for the present numerical computations. Chen, Y.-S. and Kim, S.-W. Unspecified Center NASA-CR-179204, NAS 1.26:179204 NAS8-35918
Computation of Turbulent Flows Using an Extended K-Epsilon Turbulence Closure Model
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781724264602
Category :
Languages : en
Pages : 30
Book Description
An extended kappa-epsilon turbulence model is proposed and tested with successful results. An improved transport equation for the rate of dissipation of the turbulent kinetic energy, epsilon, is proposed. The proposed model gives more effective response to the energy production rate than does the standard kappa-epsilon turbulence model. An extra time scale of the production range is included in the dissipation rate equation. This enables the present model to perform equally well for several turbulent flows with different characteristics, e.g., plane and axisymmetric jets, turbulent boundary layer flow, turbulent flow over a backward-facing step, and a confined turbulent swirling flow. A second-order accurate finite difference boundary layer code and a nearly second-order accurate finite difference elliptic flow solver are used for the present numerical computations. Chen, Y.-S. and Kim, S.-W. Unspecified Center NASA-CR-179204, NAS 1.26:179204 NAS8-35918
Publisher: Createspace Independent Publishing Platform
ISBN: 9781724264602
Category :
Languages : en
Pages : 30
Book Description
An extended kappa-epsilon turbulence model is proposed and tested with successful results. An improved transport equation for the rate of dissipation of the turbulent kinetic energy, epsilon, is proposed. The proposed model gives more effective response to the energy production rate than does the standard kappa-epsilon turbulence model. An extra time scale of the production range is included in the dissipation rate equation. This enables the present model to perform equally well for several turbulent flows with different characteristics, e.g., plane and axisymmetric jets, turbulent boundary layer flow, turbulent flow over a backward-facing step, and a confined turbulent swirling flow. A second-order accurate finite difference boundary layer code and a nearly second-order accurate finite difference elliptic flow solver are used for the present numerical computations. Chen, Y.-S. and Kim, S.-W. Unspecified Center NASA-CR-179204, NAS 1.26:179204 NAS8-35918
Computation of Turbulent Flows Using an Extended K-e Turbulence Closure Model
Author: Y.-S. Chen
Publisher:
ISBN:
Category :
Languages : en
Pages : 22
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 22
Book Description
Analysis of the K-Epsilon Turbulence Model
Author: B. Mohammadi
Publisher:
ISBN:
Category : Mathematics
Languages : en
Pages : 222
Book Description
Aimed at applied mathematicians interested in the numerical simulation of turbulent flows. Centered around the k-&epsis; model, it also deals with other models such as one equation models, subgrid scale models and Reynolds Stress models. Presents the k-&epsis; method for turbulence in a language familiar to applied mathematicians, but has none of the technicalities of turbulence theory.
Publisher:
ISBN:
Category : Mathematics
Languages : en
Pages : 222
Book Description
Aimed at applied mathematicians interested in the numerical simulation of turbulent flows. Centered around the k-&epsis; model, it also deals with other models such as one equation models, subgrid scale models and Reynolds Stress models. Presents the k-&epsis; method for turbulence in a language familiar to applied mathematicians, but has none of the technicalities of turbulence theory.
Numerical Solution of Turbulent Flow Past a Backward Facing Step Using a Nonlinear K-epsilon Model
Author: Charles G. Speziale
Publisher:
ISBN:
Category :
Languages : en
Pages : 52
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 52
Book Description
An Improved K-epsilon Model for Near-wall Turbulence and Comparison with Direct Numerical Simulation
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 26
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 26
Book Description
Navier-Stokes Computation of Compressible Turbulent Flows with a Second Order Closure
Author: National Aeronautics and Space Adm Nasa
Publisher:
ISBN: 9781730800474
Category :
Languages : en
Pages : 70
Book Description
A second order closure turbulence model for compressible flows is developed and implemented in a 2D Reynolds-averaged Navier-Stokes solver. From the beginning where a kappa-epsilon turbulence model was implemented in the bidiagonal implicit method of MACCORMACK (referred to as the MAC3 code) to the final stage of implementing a full second order closure in the efficient line Gauss-Seidel algorithm, numerous work was done, individually and collectively. Besides the collaboration itself, the final product of this work is a second order closure derived from the Launder, Reece, and Rodi model to account for near wall effects, which has been called FRAME model, which stands for FRench-AMerican-Effort. During the reporting period, two different problems were worked out. The first was to provide Ames researchers with a reliable compressible boundary layer code including a wide collection of turbulence models for quick testing of new terms, both in two equations and in second order closure (LRR and FRAME). The second topic was to complete the implementation of the FRAME model in the MAC5 code. The work related to these two different contributions is reported. dilatation in presence of stron shocks. This work, which has been conducted during a work at the Center for Turbulence Research with Zeman aimed also to cros-check earlier assumptions by Rubesin and Vandromme. Haminh, Hieu and Kollmann, Wolfgang and Vandromme, Dany Unspecified Center...
Publisher:
ISBN: 9781730800474
Category :
Languages : en
Pages : 70
Book Description
A second order closure turbulence model for compressible flows is developed and implemented in a 2D Reynolds-averaged Navier-Stokes solver. From the beginning where a kappa-epsilon turbulence model was implemented in the bidiagonal implicit method of MACCORMACK (referred to as the MAC3 code) to the final stage of implementing a full second order closure in the efficient line Gauss-Seidel algorithm, numerous work was done, individually and collectively. Besides the collaboration itself, the final product of this work is a second order closure derived from the Launder, Reece, and Rodi model to account for near wall effects, which has been called FRAME model, which stands for FRench-AMerican-Effort. During the reporting period, two different problems were worked out. The first was to provide Ames researchers with a reliable compressible boundary layer code including a wide collection of turbulence models for quick testing of new terms, both in two equations and in second order closure (LRR and FRAME). The second topic was to complete the implementation of the FRAME model in the MAC5 code. The work related to these two different contributions is reported. dilatation in presence of stron shocks. This work, which has been conducted during a work at the Center for Turbulence Research with Zeman aimed also to cros-check earlier assumptions by Rubesin and Vandromme. Haminh, Hieu and Kollmann, Wolfgang and Vandromme, Dany Unspecified Center...
Thermofluid Dynamics of Turbulent Flows
Author: Michele Ciofalo
Publisher: Springer Nature
ISBN: 303081078X
Category : Technology & Engineering
Languages : en
Pages : 194
Book Description
The book provides the theoretical fundamentals on turbulence and a complete overview of turbulence models, from the simplest to the most advanced ones including Direct and Large Eddy Simulation. It mainly focuses on problems of modeling and computation, and provides information regarding the theory of dynamical systems and their bifurcations. It also examines turbulence aspects which are not treated in most existing books on this subject, such as turbulence in free and mixed convection, transient turbulence and transition to turbulence. The book adopts the tensor notation, which is the most appropriate to deal with intrinsically tensor quantities such as stresses and strain rates, and for those who are not familiar with it an Appendix on tensor algebra and tensor notation are provided.
Publisher: Springer Nature
ISBN: 303081078X
Category : Technology & Engineering
Languages : en
Pages : 194
Book Description
The book provides the theoretical fundamentals on turbulence and a complete overview of turbulence models, from the simplest to the most advanced ones including Direct and Large Eddy Simulation. It mainly focuses on problems of modeling and computation, and provides information regarding the theory of dynamical systems and their bifurcations. It also examines turbulence aspects which are not treated in most existing books on this subject, such as turbulence in free and mixed convection, transient turbulence and transition to turbulence. The book adopts the tensor notation, which is the most appropriate to deal with intrinsically tensor quantities such as stresses and strain rates, and for those who are not familiar with it an Appendix on tensor algebra and tensor notation are provided.
Developments in Computational Modeling of Turbulent Flows
Author: Tsan-Hsing Shih
Publisher:
ISBN:
Category : Turbulence
Languages : en
Pages : 34
Book Description
Publisher:
ISBN:
Category : Turbulence
Languages : en
Pages : 34
Book Description
Analysis of the K-epsilon Turbulence Models for Simulation of Compressible Flows
Author: Krishnendu Sinha
Publisher:
ISBN:
Category :
Languages : en
Pages : 436
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 436
Book Description
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 602
Book Description
Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 602
Book Description
Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.