[James Anawati]

I would like for the reference speeds (magUInf) in the forceCoeffs and forces functions to change as a function of time.


My goal is to calculate the added mass of a body in a flow. Currently, I have created a case where an ellipsoid is suspended in a flow which accelerates and then decelerates. However, the functions that calculate and report the forces and force coefficients only seem to allow for a single value for the reference speed. To correctly calculate the forces and force coefficients, the reference speed should be the same as the speed of the flow at any given time.


The table I am using for the input flow velocity is as follows.


uniformValue table
(
(0 (1.5 0 0))
(1.5 (1.5 0 0))
(3 ( 3 0 0))
(4 ( 3 0 0))
(6 ( 1 0 0))
);



I have noticed that if I manually change the value of magUInf in the forces file while the case is running, the change is reflected in the magnitudes of the reported forces. Therefore, if I can retrieve the current simulation time in the forces function and use if statements to assign the flow speed to the magUInf variable, that should solve my issue.


For context, I am attempting to recreate the results from the paper "A new CFD method for determination of translational added mass coefficients of an underwater vehicle" by Ehsan Javanmard, Shahriar Mansoorzadeh, and Javad A. Mehr (2020), Ocean Engineering.


I am new to CFD and OpenFoam.


Thank you for your help!