|
[Sponsors] |
Multiphase modeling -evaporation condensation |
|
LinkBack | Thread Tools | Search this Thread | Display Modes |
October 1, 2020, 17:17 |
Multiphase modeling -evaporation condensation
|
#1 |
New Member
SAJA AL-RIFAI
Join Date: Feb 2020
Posts: 11
Rep Power: 6 |
hello,
I've tried to model heat and mass transfer in the cross flow staggered heat exchanger using the multiphase flow, where the condensation take place at the outer surface of the inner tube where the tube material is porous material. I model the multiphase model with the species transport. I've tested both models available in fluent (Eulerian and VOF), and I faced the same problem: 1. When I turn on the mass transfer, using the evaporation-condensation model, the outlet temperature of the both fluid looks wired, the outlet temperature of the hot fluid change only from 355 K to 342 K, and for the cold fluid the outlet temperature changes from 293.5 to 288. this is should be wrong based on the conservation of energy. 2. When I turn off the mass transfer, and run the simulation, the outlet temperature reasonable for both fluid, the hot fluid from 355 to 311 K, the cold fluid from 293 to 298 K. 3. I wrote a simple UDF (without turning on the mass transfer) to model the condensation/evaporation and calculate the mass transfer from the water vapor to the water liquid. The condensation rate was reasonable, but the tempearture as in case 1. Anyone can explain the results in case of using the evaporation-condensation mass transfer in case 1 and 2. I used the same geometry and boundary condition to simulate the single phase flow and I validate the results against the experimental data. everything was okay. thank you saja |
|
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Evaporation Modeling | gerardorg | Fluent Multiphase | 3 | June 8, 2017 15:14 |
Water evaporation and condensation in a fixed bed dryer | Yuting | FLUENT | 0 | January 30, 2017 03:33 |
modeling condensation on surface | bhanu1810 | STAR-CCM+ | 0 | August 26, 2012 13:43 |
Problems with multiphase modeling | magnounibo | FLUENT | 0 | April 30, 2009 04:59 |
Water Evaporation and condensation modeling | Linjie | CFX | 6 | May 24, 2007 15:55 |