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Reservoir EngineeringWaterflooding and EOR

Fraction of Injected Heat Remaining in Reservoir Formula

Eh=QQiE_h=\frac{Q}{Q_i}

Fraction of Injected Heat Remaining in Reservoir calculates fraction of injected heat remaining in reservoir for waterflooding and eor workflows in reservoir engineering.

Calculate

How engineers use this formula

Use this formula when the listed inputs (Q, Q_i) 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, E_h equals 0.6 fraction.

QBTU

600000

Q_iBTU

1000000

Inputs

Q

BTU

Total heat remaining in reservoir

Q_i

BTU

Total heat injected

Outputs

E_h

fraction

Fraction of injected heat remaining in reservoir

Q

BTU

Total heat remaining in reservoir

Q_i

BTU

Total heat injected

Source and review

reviewed

Thermal Recovery, Prats, M. (1986)

Prats, M. 1986. Thermal Recovery. Society of Petroleum Engineers, New York, Chapter 5, Page 44.

Source

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