heat rate passing through a wall

[Marco Scapinello]

Hello,

I am a quite new user of Cantera.

I try to model a reactor as 2 multiple CSTR series in paralel as shown in the picture.

The first serie (CSTR 1-->n) exchange some mass with the second serie (CSTR 1'-->n'), while the second series has some thermal losses with the environment.

I modeled the first exchange as two mass flow controllers in opposite direction and with the same amount of flowrate. In addition I added a wall to evaluate the heat involved in the exchange.

here the line of code to define the variables:

#-------

mix=(CSTR_1.density+CSTR_1'.density)/2*(Deff/R)*Area_step_reactor/9

MFC_1=ct.MassFlowController(upstream=CSTR_1, downstream=CSTR_1', mdot=mix)

MFC_1'=ct.MassFlowController(upstream=CSTR_1', downstream=CSTR_1, mdot=mix)

q1=( CSTR_1.thermal_conductivity+ CSTR_1'.thermal_conductivity)/2*( CSTR_1.T-CSTR_1'.T)/R

w = ct.Wall(CSTR_1, CSTR_1' , A=Area_step_reactor, Q=q1)

#------

For the second exchange I have just defined just a wall with normal thermal losses due to convection and radiation

#-----

w2= ct.Wall(  CSTR_1' , environment, A=Area'_step_reactor, U=5)
w2.emissivity=0.3

#-----  

I wanted to know how I can get the processed value in the simulation for both the exchanges in order to have the termal losses to the environment.

I thougth to get using the heat_release_rate accessible in the ct.SolutionArray for STR1 and CSTR_1' but in these values there are also the contribution of reaction or calculate manually getting the temperature and using the same equation the solver use. but I would like to have something more direct.

Thanks in advance

Best regards

Marco 

[Ray Speth]

Hi Marco,

I think what you’re looking for is the heat_rate property of the Wall object.

Regards,
Ray

​

[Marco Scapinello]

Many thanks

Tested and it worked properly.

Regards

Ray