Coupling VOL - CWS
The VOL module needs to be coupled with the CWS module. The goal is to have a limited cell growth if the precursors are not provided by MET. On the other hand the cell wall synthesis should be stopped when the turgor pressure is not expanding the cell.
We decided to couple the modules by connecting phi, expansion rate of reference volume (extensibility = 1/viscosity) with the CW synthesis using a logistic function, if the difference between the CW mass and the theoretical mass (Vref * ρCW) is zero the value should be 1e-4 as before.
In the CW module we replace the logistic function by the expansion rate of Vref (dVref). The reference volume (Vref) is always larger than zero and limited in the VOL module.