In-Situ Combustion Temperature Increase Rate Formula
In-Situ Combustion Temperature Increase Rate calculates temperature increase rate for waterflooding and eor workflows in reservoir engineering.
How engineers use this formula
Use this formula when the listed inputs (S_o, rho_o, phi, n_oxy, A_c, P_O2, M_r, E_a, R, T_ab) are known and the assumptions behind the cited waterflooding and eor relationship match the engineering case being checked.
Assumptions
- Input values are representative for the well, reservoir, fluid, or equipment case being evaluated.
- The declared units match the field-unit constants used in the formula.
- The cited formula applies to the selected petroleum engineering workflow.
Limitations
- The calculation does not replace a full engineering model or operating procedure.
- Accuracy depends on the source correlation, assumptions, input quality, and unit consistency.
Common mistakes
- Mixing unit systems without converting the inputs.
- Using default example values as field recommendations.
- Applying the formula outside the source assumptions.
Default example
Using the default inputs, dT_dt equals 0.000136 K/s.
0.6
53
0.25
1
0.00001
50
35
20000
1.986
900
Inputs
S_o
fractionOil Saturation
rho_o
lbm/ft^3Oil Density
phi
fractionPorosity
n_oxy
dimensionlessOxygen Pressure Exponent
A_c
1/F-psiPre-Exponential Constant
P_O2
psiPartial Pressure of Oxygen
M_r
BTU/ft^3-FVolumetric Heat Capacity of Reservoir
E_a
BTU/lbmolActivation Energy
R
BTU/lbmol-KGas Constant
T_ab
KAbsolute Temperature
Outputs
dT_dt
Temperature Increase Rate
A_c
Pre-Exponential Constant
S_o
Oil Saturation
phi
Porosity
rho_o
Oil Density
M_r
Volumetric Heat Capacity of Reservoir
P_O2
Partial Pressure of Oxygen
n_oxy
Oxygen Pressure Exponent
E_a
Activation Energy
T_ab
Absolute Temperature
Source and review
reviewedThermal Recovery, Prats, M. (1986)
Prats, M. 1986. Thermal Recovery. Society of Petroleum Engineers, New York, Chapter 8, Page 95.