209 Enthalpy Exchanger in Heating Mode

This component calculates the effectiveness and outlet conditions of an 
enthalpy exchanger operating in the heating mode.  In operating conditions 
without excess water, the regenerator is operated at a rotation speed such 
that the maximum effectivenesses which is only a function of the number of 
transfer units is achieved.  If there is a risk of excess water, the rotation 
speed is lowered to avoid condensation in the exhaust stream.  In that case 
the effectiveness and the corresponding air outlet states are calculated by 
an empirical correlation as a function of rotation speed, outdoor temperature 
and number of transfer units.  For the definition of excess water and the 
exact equations see Stiesch [1].  

The enthalpy exchanger is controlled such that it operates only between 6 AM 
and 9 PM and if the outdoor temperature is below 18C.

The module requires a weather generator and a psychrometric conversion module.

Parameters (4):
1       Tei:            Exhaust Inlet (Indoor) Temperature
2       wei:            Exhaust Inlet (Indoor) Humidity Ratio
3       mfsup:          Mass Flow Rate of Supply Air Stream
4       NTU:            Number of Transfer Units Between Air and Matrix

Inputs (2):
1       Tsi:            Supply Inlet (Outdoor) Temperature
2       wsi:            Supply Inlet (Outdoor) Humidity Ratio

Outputs (12):
1       Tso             Supply Outlet Temperature
2       wso             Supply Outlet Humidity Ratio
3       Teo             Exhaust Outlet Temperature
4       weo             Exhaust Outlet Humidity Ratio
5       di              Enthalpy Difference between Supply In- and Outlet
6       Qrec            Recovered Energy Rate (Sensible + Latent Energy)
7       Et              Effectiveness for Temperature Transfer
8       Ew              Effectiveness for Humidity Transfer
9       Ei              Effectiveness for Enthalpy Transfer
10      Gamma           Dimensionless Rotation Speed ("Matrix Flow Rate" 
			to Air Flow Rate)
11      Qrecsens        Recovered Energy Rate (Sensible Energy Only)
12      hr              Period of Actual Operation

Reference:

1       Stiesch, G., Performance of Rotary Enthalpy Exchangers, M.S. Thesis 
	in Mechanical Engineering, University of Wisconsin, 1994