Ratio of current Intakes to current Offtakes:
| (1) | {\rm IVRR} = \frac{\rm Intakes}{\rm Offtakes} = \frac{q^{\downarrow}_t}{q^{\uparrow}_t} |
It is normally calculated for the whole field or its sector and represents one of the key Production Analysis metrics.
The most popular case of using IVRR metrics is waterflood FDP in Black Oil reservoir where VRR takes form:
| (2) | {\rm IVRR} = \frac{B_w \, q^{\downarrow}_{WI} + B_g \, q^{\downarrow}_{GI}}{B_w \, q^{\uparrow}_W + B_o \, q^{\uparrow}_O + B_g \, [ q^{\uparrow}_G - R_s \, q^{\uparrow}_O] } = \frac{B_w \, q^{\downarrow}_{WI}+B_g \, q^{\downarrow}_{GI}}{B_w \, q^{\uparrow}_W + [ B_o + B_g \, ( {\rm GOR} - R_s) ] \, q^{\uparrow}_O } |
where
q^{\downarrow}_{WI}, \ q^{\downarrow}_{GI} | water injection and gas injection surface flowrates |
q^{\uparrow}_W, \, q^{\uparrow}_O, \, q^{\uparrow}_G | water, oil, gas surface flowrates |
B_w, \, B_o, \, B_g | formation volume factors between separator and sandface pressure/temperature conditions |
| GOR | production Gas-Oil Ratio |
R_s | Solution GOR at sandface pressure/temperature conditions |
When gas injection is not present ( q^{\downarrow}_{GI} = 0) the alternative form of IVRR equation can be derived from (2):
| (3) | {\rm IVRR} = \frac{q^{\downarrow}_{WI}}{q^{\uparrow}_W + \left[ \frac{B_o}{B_w} + \frac{B_g}{B_w} \, ( {\rm GOR} - R_s) \right] \, q^{\uparrow}_O } = \frac{q^{\downarrow}_{WI}}{q^{\uparrow}_O} \cdot \frac{1}{{\rm WOR} + \left[ \frac{B_o}{B_w} + \frac{B_g}{B_w} \, ( {\rm GOR} - R_s) \right] } = \frac{1}{\rm IPIR} \cdot \frac{1}{\frac{Y_w}{1-Y_w} + \left[ \frac{B_o}{B_w} + \frac{B_g}{B_w} \, ( {\rm GOR} - R_s) \right] } |
where
See Also
Petroleum Industry / Upstream / Production / Subsurface Production / Field Study & Modelling / Production Analysis
[ Offtakes ] [Intakes] [ Cumulative Voidage Replacement Ratio (ΣVRR) ]