# Vasquez and Beggs Oil Compressibility correlation

## Vasquez and Beggs Oil Compressibility correlation

Vasquez and Beggs is an empirical correlation for the oil compressibility published in 1980[1].

Vasquez and Beggs Oil Compressibility correlation in the PVT Software

## Math & Physics

$c_o = \frac{28.1R_s+30.6T-1180SG_g+\frac{1784}{SG_o}-10910}{10^5P}$[2]

## Example. Calculation of the oil compressibility

Example source [3]

### Input data

$R_s$ = 53.24 sm3/sm3 at P = 10 MPa
$T$ = 90C or 363K
$SG_o$ = 0.85 or 35 API
$SG_g$ = 0.75

Calculate oil compressibility at p = 10 MPa?

### Solution

$c_o$ = 0.002907 MPa-1 or 2.95E-4 atm

The solution is available in the online PVT calculator software model at www.pengtools.com

## Nomenclature

$c_o$ = oil compressibility, MPa-1
$P$ = pressure, MPa
$R_s$ = solution gas-oil ratio, sm3/sm3
$SG_g$ = gas specific gravity, dimensionless
$SG_o$ = oil specific gravity, dimensionless
$T$ = temperature, °K

## References

1. Vasquez, M.; Beggs, H.D. (1980). . Journal of Petroleum Technology. Society of Petroleum Engineers. 32 (SPE-6719-PA).
2. Afanasyev, Vitaliy; Moskvin, Igor; Wolcott, Ken; McCain, W.D. (2004). "Practical PVT Calculations for black oils". YUKOS publication.
3. Wolcott, Don (2009). . Houston: Energy Tribune Publishing Inc.