Richard Mechanics: Suction pressure cut-off, Boiling water-table, linear type liquid density

[Laxman]

Hello everyone,

I am running a rainfall plus reservoir water fluctuation induced landslide model using a Richards Mechanics process. During model preparation, I am facing a few difficulties and have few queries.

1. Setting suction pressure cut-off.
Is it possible to set maximum suction pressure cut-off in OGS as given in the following figure?

2. Boiling water table.
If initial pore water distribution is defined and the model is run to get the equilibrated water table. The water table boils and then settles afterwards. This could be avoided by using a large initial time step, but is there any other way to prevent groundwater from boiling?
I have prepared a simple test case for that:BoilingGroundwater.zip (171.0 KB)

3. Linear type density for AqueousLiquid phase
Recently updated benchmarks have a linear type density parameter for the liquid phase. What does that mean? Actually, this property tends to stop boiling groundwater but how to find slope and reference condition for a particular case?

Thank you,
Laxman Kafle

[joergbuchwald]

Hi Laxman,
concerning your third question:
The density is usually not constant if temperature or pressure changes. In the linear regime the water density changes with respect to pressure with compressibility as slope. Earlier implementations decoupled the density relationship and bulk modulus/compressiblity allowing the user to provide inconsistent input. The reference condition is set with respect to the reference value.
The data can be obtained e.g, here: Density of Liquids versus change in Pressure and Temperature