skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: A computationally efficient P 1 radiation model for modern combustion systems utilizing pre-conditioned conjugate gradient methods

Authors:
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1416641
Grant/Contract Number:
FE0026191
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Applied Thermal Engineering
Additional Journal Information:
Journal Volume: 119; Journal Issue: C; Related Information: CHORUS Timestamp: 2018-01-11 12:24:42; Journal ID: ISSN 1359-4311
Publisher:
Elsevier
Country of Publication:
United Kingdom
Language:
English

Citation Formats

Krishnamoorthy, Gautham. A computationally efficient P 1 radiation model for modern combustion systems utilizing pre-conditioned conjugate gradient methods. United Kingdom: N. p., 2017. Web. doi:10.1016/j.applthermaleng.2017.03.055.
Krishnamoorthy, Gautham. A computationally efficient P 1 radiation model for modern combustion systems utilizing pre-conditioned conjugate gradient methods. United Kingdom. doi:10.1016/j.applthermaleng.2017.03.055.
Krishnamoorthy, Gautham. Thu . "A computationally efficient P 1 radiation model for modern combustion systems utilizing pre-conditioned conjugate gradient methods". United Kingdom. doi:10.1016/j.applthermaleng.2017.03.055.
@article{osti_1416641,
title = {A computationally efficient P 1 radiation model for modern combustion systems utilizing pre-conditioned conjugate gradient methods},
author = {Krishnamoorthy, Gautham},
abstractNote = {},
doi = {10.1016/j.applthermaleng.2017.03.055},
journal = {Applied Thermal Engineering},
number = C,
volume = 119,
place = {United Kingdom},
year = {Thu Jun 01 00:00:00 EDT 2017},
month = {Thu Jun 01 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1016/j.applthermaleng.2017.03.055

Citation Metrics:
Cited by: 1work
Citation information provided by
Web of Science

Save / Share:
  • Large, sparse systems of linear equations as found in several power system problems are generally solved using direct LU decomposition methods. Although these techniques are considered efficient for most applications, in cases involving repeated solutions such as security analysis or real time control, direct solvers may still not be sufficiently fast. The incomplete Cholesky preconditioned conjugate gradient (PCG) algorithm is a very powerful semi-iterative solver which has been proven to have significant speed advantages over direct methods in the area of finite element electromagnetic analysis (ratios of 100 to 1 are not uncommon). In this paper, the PCG algorithm ismore » applied to the fast decoupled load flow and to the DC load flow. The computation time of the new PCG algorithm is compared with that of a standard direct solver for a wide spectrum of power networks up to 5,000 buses and 10,000 lines. The results of the numerical experiments indicate that for certain classes of large sparse systems or for repeated solutions with matrix modifications, the PCG method is significantly more efficient than direct techniques and offers important savings in CPU time.« less
  • The authors consider large, sparse linear systems that result from the discretization of partial differential equations on regular and irregular domains, and they focus on the application of the preconditioned conjugate gradient (PCCG) method to the solution of such systems. More specifically, the goal is the efficient implementation of the PCCG method on vector supercomputers. The contribution to the above goal is made by the introduction of a data structure that can be effectively manipulated on vector machines, the utilization of preconditioning matrices obtained by incomplete factorization with diagonal update sets, and the introduction of new numbering schemes for bothmore » regular and irregular grids.« less
  • The technique of the initial guess calculation for the conjugate gradient method is proposed. Computational schemes of the linear system solution with symmetrical positive definite matrices are constructed on its basis. Their efficient modifications for systems with five-diagonal matrices are proposed. The investigation of the developed methods using the problem of two-dimensional numerical simulation of bipolar transistors has been carried out. Experimental evidence of the proposed method's efficiency has been obtained. 30 refs., 6 figs., 1 tab.
  • For efficient and accurate temperature predictions of sodium fast reactor structures, a 3-D full-core conjugate heat transfer modeling capability is developed for an advanced system analysis tool, SAM. The hexagon lattice core is modeled with 1-D parallel channels representing the subassembly flow, and 2-D duct walls and inter-assembly gaps. The six sides of the hexagon duct wall and near-wall coolant region are modeled separately to account for different temperatures and heat transfer between coolant flow and each side of the duct wall. The Jacobian Free Newton Krylov (JFNK) solution method is applied to solve the fluid and solid field simultaneouslymore » in a fully coupled fashion. The 3-D full-core conjugate heat transfer modeling capability in SAM has been demonstrated by a verification test problem with 7 fuel assemblies in a hexagon lattice layout. In addition, the SAM simulation results are compared with RANS-based CFD simulations. Very good agreements have been achieved between the results of the two approaches.« less