# FLUENT 5 - Specifying a transient variation for the Heat flux on a radiator boundary condition

 (This is one of the workarounds mentioned in CR 11746 for Specifying transient heat flux on a radiator -bc zone) The Scheme file enclosed below describes a somehow cumbersome way to specify a time variation of the heat flux bc on a radiator bc zone. An enhancement in the regular code will be desired. ;; this is a Scheme function changing the heat flux bc value ;; on a radiator bc zone in time ;; ;; make your changes in this area of the function ;; ;; then load the function using File>Read>Scheme ;; or text command (load "tran-hf.scm") ;; after loading and doing other setups, type ;; (trans-run) in the console window as a text command ;; ;; ;; name of the radiator zone (define rad-zone-name "pass") ;; coefficients of the curve fit (define a5 1) (define a4 1) (define a3 1) (define a2 1) (define a1 1) (define a0 1) ;; number of time steps to be run (define ntimesteps 300) ;; number of iterations per time step (define itpertimestep 20) ;; time step magnitude (rpsetvar 'physical-time-step 5) ;; ;; Do not change below this line ;;=========================================== (define t) (define radiator-hf) (define (polynom5 x) (let* ((x2 (* x x)) (x3 (* x2 x)) (x4 (* x3 x)) (x5 (* x4 x))) (+ (* a5 x5) (* a4 x4) (* a3 x3) (* a2 x2) (* a1 x) a0))) (define (trans-run) (let loop ((i 0)) (if (< i ntimesteps) (begin (set! t (rpgetvar 'flow-time)) (set! radiator-hf (polynom5 t)) (ti-menu-load-string (string-append "/def/bc/rad/ " rad-zone-name " , , constan t 0 0 " (number->string radiator-hf))) (ti-menu-load-string (string-append "/solve dual-time-iterate 1 " (number->stri ng itpertimestep))) (loop (+ i 1))))))

 No comments yet. Be the first to add a comment!