|
[Sponsors] |
April 21, 2022, 15:18 |
RPI Boiling model for mcirochannel
|
#1 |
New Member
Suraj A Bolaj
Join Date: Apr 2022
Posts: 4
Rep Power: 4 |
Hi there,
We are performing analysis on rectangular microchannel Geometry: 40mm long x 0.24mm wide x 0.5mm height Working Fluid: Water-liquid and water-vapour Models:- Multiphase: Eulerian, RPI boiling model Energy equation: on Viscous: k-epsilon, RNG, Standard wall functions, mixture. Boundary Conditions: temp=323k, Inlet velocity=0.826m/s at 1 bar pressure Outlet(pressure outlet): water liquid(temp=373.15), water vapour(temp=373.15) 3 sides wall heated(copper wall) heat flux=500kw/m^2 (bottom, left, right walls), top wall(polycarbonate Laxen) heat flux=0 Methods:- Scheme: Coupled Gradient: Least squares cell-based Pressure: Second order Momentum: Second order upwind Volume fraction: QUICK Turbulent Kinetic Energy: Second order upwind Turbulent Dissipation Rate: Second order upwind Energy: Second order upwind During Initialization I am facing an error indicating the Turbulent viscosity ratio is limited to e5 in cells..... and as the calculation proceeds the cells reduces after 500 iterations I got this error: Experiencing convergence difficulties - temporarily relaxing and trying again... Experiencing convergence difficulties - temporarily relaxing and trying again... Experiencing convergence difficulties - temporarily relaxing and trying again... Experiencing convergence difficulties - temporarily relaxing and trying again... Stabilizing pressure coupled to enhance linear solver robustness. Experiencing convergence difficulties - temporarily relaxing and trying again... Divergence detected in AMG solver: pressure coupled Stabilizing k to enhance linear solver robustness. Divergence detected in AMG solver: k Stabilizing epsilon to enhance linear solver robustness. Divergence detected in AMG solver: epsilon Stabilizing temperature to enhance linear solver robustness. Stabilizing vof-1 to enhance linear solver robustness. Divergence detected in AMG solver: vof-1 Error at host: floating point exception Error at Node 0: floating point exception ===============Message from the Cortex Process================================ Compute processes interrupted. Processing can be resumed. ================================================== ============================ Error: floating point exception Error Object: #f Registering ReportDefFiles, ("C:\Users\91960\Desktop\Major project\rectangular channel\tough assignment_files\dp0\FLU\Fluent\mass-flow-rate-rfile.out" "C:\Users\91960\Desktop\Major project\rectangular channel\tough assignment_files\dp0\FLU\Fluent\report-file-0.out") Error: WorkBench Error: Could not handle event: SolutionStatusUpdate Error Object: #f Calculation complete. Can anyone help me with this? Thank you |
|
April 29, 2022, 06:27 |
|
#2 |
New Member
Neeraj Kumar Vidhyarthi
Join Date: Apr 2022
Posts: 4
Rep Power: 4 |
multiphase model should be used here is homogenous
|
|
January 24, 2024, 10:07 |
|
#3 |
New Member
marcus aurelius
Join Date: Sep 2023
Posts: 18
Rep Power: 3 |
What is homogeneous model?
I still have fundamental question, can we use RPI wall boiling model for microchannels where the width can be as small as 0.2 mm? |
|
Tags |
eulerian multiphase model, fluent, microchannel, rpi model, rpi wall boiling |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Boiling Model Saturation Model | charles4allme | OpenFOAM Running, Solving & CFD | 0 | April 4, 2020 21:27 |
[swak4Foam] swakExpression not writing to log | alexfells | OpenFOAM Community Contributions | 3 | March 16, 2020 19:19 |
Multiphase wall boiling model | omaralyahia | CFX | 4 | July 14, 2015 22:41 |
Wall temperature in RPI model. | roxor | Fluent Multiphase | 0 | May 1, 2015 23:16 |
Superlinear speedup in OpenFOAM 13 | msrinath80 | OpenFOAM Running, Solving & CFD | 18 | March 3, 2015 06:36 |