Comparison of methods for solving nonlinear finite-element equations in heat transfer

Conference · Thu Jan 01 04:00:00 EST 1981

OSTI ID:5314339

Cort, G E; Graham, A L; Johnson, N L

We have derived two new techniques for solving the finite-element heat-transfer equations with highly nonlinear boundary conditions and material properties. When compared with the more commonly employed successive substitution and Newton-Raphson procedures, the new methods speed convergence rates and simultaneously increase the radius of convergence. We have observed reductions in computation time in excess of 80% when the new techniques are employed. The first method accelerates the standard Newton-Raphson approach when the degree of the nonlinearity is known (for example, radiation boundary conditions or a prescribed temperature dependence in the thermal conductivity). The second technique employs feedback to regulate the solution algorithm during execution. Comparisons of these techniques are given for several practical examples.

• Research Organization: Los Alamos National Lab., NM (USA)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 5314339
• Report Number(s): LA-UR-81-3321; CONF-820604-2; ON: DE82004338
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420400* -- Engineering-- Heat Transfer & Fluid Flow
COMPARATIVE EVALUATIONS
ENERGY TRANSFER
FINITE ELEMENT METHOD
HEAT TRANSFER
MATHEMATICAL MODELS
NUMERICAL SOLUTION