I would like to know what is the proper way to inject some flow in a fracture, defined as a discrete feature in a 2D vertical model: I already thought (and tried) various flow BCs such as fluid-flux or Well BC, or trying to use the discrete feature source/sink property.

However, none of these methods seems correct: among the encountered problems, the fracture displays strong variations of saturation/pressure/head, while it is expected to present similar characteristics along the whole length.

Another question about the same problem definition: where should be defined the temperature of the injected fluid?

Thank you for your help