Abstract

Multiphase vertical flow is found in practically every tubing string of oil producing wells. As a valuable tool, knowledge of the aspects of multiphase vertical flow are necessary to predict pressure traverses in order to correctly design completion strings, flow rates estimation and for designing a suitable artificial lift installation for a particular well. When fluids are produced energy is dissipated or wasted. Knowledge about such losses is a particular requirement for minimizing the energy loss, and it may be significant in the entire length of the tubing string. Most progress towards a solution of the problem associated with multiphase vertical flow has been made by previous investigators using some form of basic energy balance equation. Continued improvement in these efforts will permit much greater accuracy for absolutely clean tubing strings. Actual situations in South Palembang District oil wells having scale deposits, paraffin, viscous oil and other effects, will always leave doubts when using existing correlations other than for clean pipes. To overcome this situation, several tests have been conducted on oil wells with average high water cuts to determine an appropriate friction factor term for the South Palembang District oil fields that can be used in vertical flow formulas.

A set of working curves could then be prepared for the practicing engineer to utilize for analysis (since he does not always have a large computer program available for immediate pressure loss calculations): With practical application in the South Palembang District, production engineers become more aware of the benefits that can be directly obtained from the proper use of vertical flow calculations. A simple and time saving procedure is presented for obtaining flowing gradient curves by using a hand held programmable calculator.