# Simulation of a Vertical Channel

## Description

This case is designed for testing the implementation of the virtual mass. The
geometry consists of a rectangular channel, which is initialised with alpha.air
= alpha.water = 0.5. As buoyancy acts on the disperse gas bubbles, the air
accelerates and the water decelerated, while the volume fraction of the air
shrinks due to mass conservation. A steady-state is reached after a short time.

## Technical Information

- 1D
- 80 cells
- grading 16
- 1 m
- gravitational acceleration
- linear drag coupling (Ki = 8000)
- virtual mass (Cvm = 0.5)
- partialElimination

The test case is designed to run an automatic time step study. Enter the desired
deltaT values in the bash array in Allrun and OpenFOAM will run the cases.

## Pre-Processing

No special pre processing is necessary.

## Post-Processing

A createGraphs script is available in the validation directory, but has to be
run manually.

## Keywords

multimorph, channel flow

## Additional Remarks

This case is set up in the same way as the case in the "Cases" repository of
the same name is. The present case differs from the other one in terms of
shorter run time and does not feature any post processing.

## Literature
