HydroGeoSphere/Zero-Order Source

A zero-order source is one in which the medium itself produces a solute. For example, some soils produce radon gas as a result of radioactive decay.

Zero order source

npanel Number of panels in the time-variable, zero-order source function. For each panel, enter the following:

(a) ton_val,toff_val, (bc_val(j),j=1,nspeciesmob) Time on [T], time off [T] and mass of solute produced per unit volume of porous medium solids per unit time [M L⁻³].

Nodes in the chosen zones area are assigned zero-order source boundary conditions.

A panel is a point in time at which the source term is set to a new value. The first panel would normally start at time zero. The source term given for the last panel will be maintained until the end of the simulation. You can assign a static source term for the duration of the simulation by setting npanel to 1, ton_val to 0.0 and toff_val to a large number.

Note that if nspeciesmob is greater than 1, additional values of bc_val should be included.

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