\Delta Q = - \frac{B_o - R_s \, B_g}{1- R_s \, R_v} \cdot \, Q^{\uparrow}_O + \frac{ B_g - R_v \, B_o}{1- R_s \, R_v} \cdot \, \left( Q^{\downarrow}_G - Q^{\uparrow}_G + Q^{\downarrow}_{GCAP} \right) + B_w \, \left( Q^{\downarrow}_W - Q^{\uparrow}_W + Q^{\downarrow}_{WAQ} \right) |
If Aquifer Expansion and/or Gas Cap expansion are unknown they are simply ignored for the first pressure modelling run: .
They can be adjusted at the next model runs by fitting formation pressure response (see Material Balance Pressure @model).
Petroleum Industry / Upstream / Production / Subsurface Production / Field Study & Modelling / Production Analysis / Voidage Replacement Balance (VRB)
[ Material Balance Pressure @model ][ Normalized Cumulative Voidage Replacement Balance (NCVRB) ]