Heat Exchanger UA From Rating Information by M. J. Brandemuehl
Revised for TRNSYS by N.Blair and R.Schwarz

      This model was adapted strictly for use with the TRNSYS Program by
the Solar Energy Laboratory.

This subroutine calculates the overall heat transfer coefficient,
UA, for heat exchanger given the design or rating information.
Rating information required includes fluid capacity rates,inlet 
state variable, and heat transfer rate.  The algorithm iteratively 
solves for UA to achieve specified heat transfer rates given fluid inlet
stream conditions.  The iterative scheme relies on the HEATEX
algorithm, which models the heat exchanger using the effectivness-Ntu
method of analysis.  Six standard heat exchanger are addressed.  

Developed by M. J. Brandemuehl for the AESHRAE TOOLKIT at
the University of Colorado at Boulder 25 May, 1992