Derivative of two volScalarFields

janGaertner · November 16, 2017, 05:35

Hello,

I am trying to implement the Homogeneous Relaxation Model (HRM) of Downar-Zapolski (1995) in interPhaseChangeFoam.
Currently I am struggling with the pressure equation and explicitly the derivative of two volScalarFields $\frac{\partial \rho}{\partial \alpha}$ which is the derivative of the density to the phase fraction alpha.
Is there already a built in function in OpenFoam or do I have to write my own method for this?
I could not find anything on the forum or in the manual. All gradients I found are only gradients in space.

The derived pressure equation is:
$\rho \nabla \cdot \left(\frac{\nabla p}{a_p}\right) - \rho \nabla \cdot \left(\frac{H(U)}{a_p}\right) = \left(\frac{\partial \rho}{\partial \alpha}\right)_{p,h} \underbrace{\left( -\alpha \frac{h_\mathrm{ML}(p,T)-h_\mathrm{SL}(p)}{h_\mathrm{SG}(p)-h_\mathrm{SL}(p)}\frac{1}{\Theta}\right)}_{\frac{\mathrm{D}\alpha}{\mathrm{D}t}}$

This pressure equation can also be found in the work of Lee et al. (Flashing flow of superheated jet fuel) and Schmidt (Multi-dimensional simulation of thermal non-equilibrium channel flow)

neelshah0034 · July 30, 2021, 17:30

Hello,

Were you able to figure out the implementation of HRM in openfoam?

If yes, Could you please help me out to find the model?

Thank you
Neel Shah

janGaertner · July 31, 2021, 10:21

Hello,

yes I have implemented the HRM model. You can find further details in the following publications. Possibly I will publish my code in the future too.
DOI: 10.1016/j.ijmultiphaseflow.2020.103360DOI: https://doi.org/10.3390/fluids6030104

Best,

Jan

neelshah0034 · August 2, 2021, 10:59

So, No one has published the HRM code for Openfoam?

Can you help me with any other that works best for Cryogenic Fluid, please?

Thank you

Lubing Xu · February 22, 2024, 07:17

Hello!

I am doing some related work in flash boiling gasoline spray, and have captured the shock waves in flash boiling jets under wide thermodynamic conditions. The HRM model in CONVERGE is used in my work, but there are some problems, and I'd like to do some comparative work. Is your Foam open source now?

Best

Lubing Xu

janGaertner · February 23, 2024, 10:32

Hello,

the code is unfortunately not publicly available that you can just download it. However, if you are interested in it please send me an e-mail and we can see if we can grant access to it.

jan-wilhelm.gaertner@itv.uni-stuttgart.de

Best,

Jan

Lubing Xu · February 27, 2024, 11:02

I will send the email soon. Is your numerical case a 2D simulation in the work Numerical and experimental analysis of flashing cryogenic nitrogen?

Best!

Lubing

Kaley2 · February 27, 2024, 13:22

So, No one has published the HRM code for compete in online plinko tournaments Openfoam?

November 16, 2017, 05:35	Derivative of two volScalarFields	#1
janGaertner New Member Jan Gaertner Join Date: Nov 2017 Posts: 17 Rep Power: 8	Hello, I am trying to implement the Homogeneous Relaxation Model (HRM) of Downar-Zapolski (1995) in interPhaseChangeFoam. Currently I am struggling with the pressure equation and explicitly the derivative of two volScalarFields $\frac{\partial \rho}{\partial \alpha}$ which is the derivative of the density to the phase fraction alpha. Is there already a built in function in OpenFoam or do I have to write my own method for this? I could not find anything on the forum or in the manual. All gradients I found are only gradients in space. The derived pressure equation is: $\rho \nabla \cdot \left(\frac{\nabla p}{a_p}\right) - \rho \nabla \cdot \left(\frac{H(U)}{a_p}\right) = \left(\frac{\partial \rho}{\partial \alpha}\right)_{p,h} \underbrace{\left( -\alpha \frac{h_\mathrm{ML}(p,T)-h_\mathrm{SL}(p)}{h_\mathrm{SG}(p)-h_\mathrm{SL}(p)}\frac{1}{\Theta}\right)}_{\frac{\mathrm{D}\alpha}{\mathrm{D}t}}$ This pressure equation can also be found in the work of Lee et al. (Flashing flow of superheated jet fuel) and Schmidt (Multi-dimensional simulation of thermal non-equilibrium channel flow)

February 27, 2024, 13:22		#8
Kaley2 New Member Lavinia Cummerata Join Date: Feb 2024 Posts: 2 Rep Power: 0	So, No one has published the HRM code for compete in online plinko tournaments Openfoam? Last edited by Kaley2; March 6, 2024 at 12:04.

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July 30, 2021, 17:30		#2
neelshah0034 New Member Neel Join Date: Apr 2021 Posts: 7 Rep Power: 5	Hello, Were you able to figure out the implementation of HRM in openfoam? If yes, Could you please help me out to find the model? Thank you Neel Shah

July 31, 2021, 10:21		#3
janGaertner New Member Jan Gaertner Join Date: Nov 2017 Posts: 17 Rep Power: 8	Hello, yes I have implemented the HRM model. You can find further details in the following publications. Possibly I will publish my code in the future too. DOI: 10.1016/j.ijmultiphaseflow.2020.103360DOI: https://doi.org/10.3390/fluids6030104 Best, Jan

August 2, 2021, 10:59		#4
neelshah0034 New Member Neel Join Date: Apr 2021 Posts: 7 Rep Power: 5	So, No one has published the HRM code for Openfoam? Can you help me with any other that works best for Cryogenic Fluid, please? Thank you

February 22, 2024, 07:17		#5
Lubing Xu New Member Join Date: Feb 2024 Posts: 5 Rep Power: 2	Hello! I am doing some related work in flash boiling gasoline spray, and have captured the shock waves in flash boiling jets under wide thermodynamic conditions. The HRM model in CONVERGE is used in my work, but there are some problems, and I'd like to do some comparative work. Is your Foam open source now? Best Lubing Xu

February 23, 2024, 10:32		#6
janGaertner New Member Jan Gaertner Join Date: Nov 2017 Posts: 17 Rep Power: 8	Hello, the code is unfortunately not publicly available that you can just download it. However, if you are interested in it please send me an e-mail and we can see if we can grant access to it. jan-wilhelm.gaertner@itv.uni-stuttgart.de Best, Jan

February 27, 2024, 11:02		#7
Lubing Xu New Member Join Date: Feb 2024 Posts: 5 Rep Power: 2	I will send the email soon. Is your numerical case a 2D simulation in the work Numerical and experimental analysis of flashing cryogenic nitrogen? Best! Lubing