Recharge in a 2D groundwater flow model

Hello to all OGS community, as the title say I am trying to establish the recharge in a 2D groundwater flow model. I have read the OpenGeoSys Tutorial Computational Hydrology I, and OpenGeoSys Tutorial Computational Hydrology 2.The examples in the tutorials are 3D models and the recharge is established in Data Explorer using a raster file with the values of recharge in m3/s. I am confused because I have currently values of recharge in m/s and I know that recharge is established in the source term file but I don’t know how to do it in a 2D model, if someone could explain me that I would be really thankful.

Your response will be very appreciated.

Thank you very much for your attention.