Drainage Radius Estimation

[elevenfourth]

Hello all !

I am doing a task of preliminary study of a field. So the wells are not drilled yet. I have the data of the grids, such as permeability, saturation, pressure, porosity. But I am not allowed to do reservoir simulations to estimate the drainage radius. All wells are vertical wells.
Do you know how to estimate the drainage radius of a well without assuming the well spacing, and by the given data only?

Thank you for your help !