[yaserbm]

we have two stream of gas mixture are joined together the first has temperature of -150C and the second has a temperature of -90, each stream has different flow rate and mole flow rate as well as different composition but they supposed to be having same pressure.

so how can we obtain the final temperature, i mean when we mixed the tow stream how much is the temperature. 

[yaserbm]

Any help from expeinced engineeres 

[yaserbm]

any help please 

[SABRY]

You need to do enthalpy balance

Total enthalpy in = total enthalpy out

If you know the specific heat, you can simplify the calculation:

1. select reference temperature e.g. the lowest temperature of the inlet stream
2. calculate the heat content for each stream at inlet using mass x specific heat x temperature difference
3. similarly calculate the heat content of outlet stream
4. solve for outlet stream temperature