A three-dimensional inverse heat conduction problem in estimating surface heat flux by conjugate gradient method

In the present study a three-dimensional (3-D) transient inverse heat condu ction problem is solved using the conjugate gradient method (CGM) and the g eneral purpose commercial code CFX4.2-based inverse algorithm to estimate t he unknown boundary heat flux in any 3-D irregular domain. The advantage of calling CFX4.2 as a subroutine in the present inverse calc ulation lies in that many difficult but practical 3-D inverse problems that can be solved under this construction. Results obtained by using the conjugate gradient method to solve these 3-D inverse problems are justified based on the numerical experiments. It is co ncluded that accurate boundary fluxes can be estimated by the CGM except fo r the final time. The reason and improvement of this singularity are addres sed. Finally, the effects of the measurement errors on the inverse solution s are discussed. (C) 1999 Elsevier Science Ltd. All rights reserved.