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 |