Consider a pair of producing well W1 and water injecting well W2 draining the same reservoir volume V_{\phi}.
General case
| (1) | \delta q = - \frac{p_{\rm DTR}(t)}{p_{\rm CTR}(t)} \cdot \delta q_I |
where t is time since the water injection rate has changed by the \delta q_I value.
Pseudo-steady state flow
| (2) | \delta q = -\frac{c_{t,I} V_{\phi, I}}{c_t V_{\phi}} \cdot \delta q_I |
Steady state flow
| (3) | \delta q = -\frac{c_{t,I} V_{\phi, I}}{c_t V_{\phi}} \cdot \delta q_I |