Pvt Simulators for Microcomputers

Fluid analysis or pressure-volume-temperature (PVT) analysis of petroleum fluids can be obtained by either laboratory analysis, empirical correlations, or through the use of equations of state. Laboratory analysis is notably accurate but is expensive, time-consuming, and requires specialized equipment and personnel. Empirical correlations are readily available and easy to use but can have inherent inaccuracies because conditions vary from those in which the correlations were developed. Fluid analysis by si mu la ti on technique using equations of state requires complex computer calculations, which until recent advances in microcomputer technology, could only be performed on mainframe computers which were capable of handling the tedious calculations and large data storage. PVT simulators have been written on mainframe computers, but few have been adapted to the microcomputer, leaving the engineer with the option of costly laboratory analysis, inconvenient timesharing, or less precise empirical correlation. The purpose of this report was to modify a PVT simulator written for a mainframe computer to run on a microcomputer. PVTBO, PVTVO, and PVTGC are a set of petroleum fluid analysis programs which have been adapted to run on an IBM-PC microcomputer. The programs provide PVT properties of a black oil, a volatile oil, and a gas condensate system, respectively, based on the Peng-Robinson equation of state. The programs can run on an IBM-PC microcomputer with at least 192K memory. Input requirements are pressure, temperature, and over-all fluid composition. The outputs for the black oil and volatile oil system include phase compositions, solution gas-oil ratios, formation volume factors, oil densities, gas gravities, relative volumes, and oil and gas viscosities. In addition, the volatile oil system includes percent liquid and gas produced, and equivalent liquid recovery. The outputs for the gas condensate system include phase compositions, condensate liquid volumes, percent gas produced, relative volumes, gas formation factors, gas viscosities, equivalent liquid recoveries.