Velarde correlation

From wiki.pengtools.com
Jump to: navigation, search

Brief

Velarde correlation is an empirical correlation for the solution gas oil ratio published in 1997. [1]

Math & Physics

R_s = \frac{R_{sr}}{R_{sb}}
R_{sr} = \alpha1 \times P^{\alpha2}_r + (1 - \alpha1) \times P^{\alpha3}_r[1]

where:

P_r = \frac{P}{P_{bp}}

A0 = 1.8653e-4
A1 = 1.672608
A2 = 0.929870
A3 = 0.247235
A4 = 1.056052

 \alpha1 = A_0 \times SG^{A_1}_g \times Y^{A_2}_{oil_API} \times {(T- 459.67)}^{A_3} \times P^{A_3}_{bp}

B0 = 0.1004
B1 = -1.00475
B2 = 0.337711
B3 = 0.132795
B4 = 0.302065

\alpha2 = B_0 \times SG^{B_1}_g \times Y^{B_2}_{oil_API} \times {(T - 459.67)}^{B_3} \times P^{B_4}_{bp}

C0 = 0.9167
C1 = -1.48548
C2 = -0.164741
C3 = -0.09133
C4 = 0.047094

\alpha3 = C_0 \times SG^{C_1}_g \times Y^{C_2}_{oil_API} \times {(T - 459.67)}^{C_3} \times P^{C_4}_{bp}

Discussion

Why the Velarde correlation?

Application range

Nomenclature

 A_1..A_{4} = coefficients
 B_1..B_{4} = coefficients
 C_1..C_{4} = coefficients
 P = pressure, MPA
 P_{bp} = bubble point pressure, MPA
 SG_g = gas specific gravity, dimensionless
 T = temperature, °R
 Y_{oil_API} = oil API gravity, dimensionless


References

  1. 1.0 1.1 Velarde, J.; Blasingame, T. A.; McCain Jr., W. D. (1997). "Correlation of Black Oil Properties At Pressures Below Bubble Point Pressure - A New Approach"Free registration required. Presented at the Annual Technical Meeting of CIM, Calgary, Alberta. Petroleum Society of Canada (PETSOC-97-93).