Outlet Stream Temperature of an Adiabatic Mixer

inlet conditions

molar flow rates in kmol/hr

air

300

water

200

temperatures in °C

air

120

water

150

Streams of air and water vapor are mixed adiabatically. Both streams are at a pressure of 1 atm. You can set the values of the molar flow rate and temperature of the two streams.

This Demonstration computes the outlet stream's temperature using the energy balance equation for nonreactive systems:



Q

=Δ



H

=

2

∑

i=1

out





n

i



H

i



-

2

∑

i=1

in





n

i



H

i



.

The specific enthalpies of air and water are computed using the temperature-dependent expressions of the constant-pressure heat capacities given in [1, Appendix B2]. In addition, we chose these reference states: air (gas) and water (vapor) both at 25 °C and 1 atm.

It is straightforward to extend this calculation to a larger number of streams and/or components.