[TRNSYS-users] time calculation

[Matthieu Cosnier]

Hello to all TRNSYS users,

I ve created a model of a "kind" of  counterflow heat exchanger. It is composed of several subunits that represents small successive parts of italong the flow. This subunits are linked  each others by the fact that the temperature of the outlet of one
is the inlet temperature of the following one etc..
I know the temperature at the inlet of on side (hot fluid)and the temperature at the inlet of the other side (cold fluid).
Each subunit is defined by a matrix system that calculate the outlet temperatures (on the cold side and on the hot side), knowing the inlet temperature of each.
My problem is that i can't solve it easily because the only temperature i know are opposite (Tinlet hot and Tinlet cold)
So i created an excel file that calculate all this equations with the option "solveur". The procedure is a step by step one, and consist of impose arbitrary values of each temperatures, to solve each system, to compare the calculated values to the imposed ones, and to start again if not.
It works very good but it's quite slow (about 5 seconds).
The problem is that i have linked this program with Trnsys
(type 62), but as you can imagine it's very long to complete my simulation because each timestep is about 5 second long.
My questions are : have i some solutions to do my simulation faster? may i use a fortran program (or another one)? and if yes, how to write it? ( i've never use fortran)

Apologize for this bad english long text
Best regards
Matthieu.

°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°
COSNIER Matthieu
Doctorant
LOCIE
ESIGEC-Université de Savoie, Campus Scientifique,
Savoie Technolac, 73376
Le Bourget-Du-Lac cedex
Tel :   06 77 75 09 31
Fax :  04 79 75 81 44
E-mail : matthieu.cosnier at etu.univ-savoie.fr
°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°