|
[Sponsors] |
Problem with Mass source, Momentum source theory |
|
LinkBack | Thread Tools | Search this Thread | Display Modes |
August 20, 2009, 06:10 |
Problem with Mass source, Momentum source theory
|
#1 |
New Member
patrick
Join Date: Mar 2009
Posts: 5
Rep Power: 17 |
Intending to model an inlet (nozzle) that is smaller than a cell in a domain, i decided to define a mass source in the cell where my inlet is supposed to be, and to add to that mass source a momentum source.
Hence I expect to rebuild the given nozzle mass flow (m_dot). Mass source UDF: m_dot/Volume _Cell Momentum source UDF: m_dot*Exit_Velocity/Volume_Cell m_dot: known from the details of the nozzle Exit_Velocity: calculated by dividing m_dot with Air_density*Exit_Area_Nozzle THE PROBLEM: on a velocity Plot of a surface crossing the chosen Cell i see a velocity distribution, where the maximum velocity is though a the chosen cell, but the amount is not near that what i had implemented (implemented Velocity was "Exit_Velocity"). THE HINK in the logic: according to the Fluent-user-guide (page 7-225) it is possible to create a mass source term (m_dot) without giving it any impuls, then create an impuls(Momentum) source term that orientates the mass. But i u look carefully at the formula of the mass source, there is already a velocity in there (logically). Then i give in Momentum source a second velocity... from there on , I'm lost. To make things easy, i chose a cell with Faces, that all have an area of 1m². Can someone please give me a clue how to manage to have a plotted maximal velocity that corresponds to implemented one.... |
|
Tags |
mass source, momentum source |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
DPM mass problem | Henrik Ström | FLUENT | 9 | May 20, 2016 11:00 |
Momentum source | Siva.K | CFX | 0 | July 10, 2008 05:49 |
Momentum Source in an accelerating frame | fakir | CFX | 7 | December 2, 2006 04:00 |
Momentum Source Convergence | Doug | CFX | 1 | June 16, 2006 05:54 |
Problem with momentum equation | Francisco | Main CFD Forum | 4 | August 5, 2004 20:04 |