The development and water-air two-phase test results of an electrical submersible pump visualization prototype

Abstract

Artificial lift systems are extensively used in the petroleum industry in order to enhance or even initiate the production of oil wells that present insufficient energy to produce naturally. The Electrical Submersible Pump (ESP) is one of the many existing artificial lift techniques and consists of assembling several diffuser type centrifugal pumps in series.It is common in petroleum field applications to have an inflow of natural gas into the pump intake, which compromises pump performance and reliability. Trying to better understand the interaction between the gas and liquid inside centrifugal pumps is still a challenge and the current investigation tries to help understand this subject.This research describes the development of a visualization prototype built using original ESP components, applying minimal mechanical and geometrical modifications, with the intent of acquiring visual evidence of the flow patterns that occur inside the pump. Because of these minimal changes to the original pump geometry, the prototype was proven to operate according to the original pump catalogue performance, implying that its hydraulic behaviour was maintained.Water-air two phase experiments were conducted at different rotational speeds (15, 20, 30 Hz) and non-slip void fractions (up to 5%) while the liquid rate was kept constant at 60% of the maximum rate at the defined shaft speed. High speed video footage was gathered, as well as differential pressure measurements.

A Review of the Electrical Submersible Pump Development Chronology

“…The working fluid in the ESP gas-liquid research was tap water, but the gas form was compressed air or nitrogen. Trevisan [42,43], Banjar [25], and Paternost [44] conducted numerous recent experimental experiments concentrating on ESP gas-management capability under viscous fluid flow.…”

State of the Art on Two-Phase Non-Miscible Liquid/Gas Flow Transport Analysis in Radial Centrifugal Pumps Part B: Review of Experimental Investigations

“…According to some studies [62][63][64][65], a higher liquid viscosity causes less turbulence, which promotes gas accumulation and performance degradation. Nevertheless, in similar studies investigating oil-gas flows, the increase in the viscosity of oil resulted in an improvement in the two-phase performance, particularly at overload conditions.…”

Estudo experimental sobre bomba centrífuga operando com fluido viscoso e escoamento bifásico gás-líquido

“…-O comportamento da bomba independe do ponto de injeção de gás e do diâmetro das bolhas na entrada. Esta questãodiâmetro das bolhas na entradaentrará em contradição com os estudos de Gamboa (2008) e Trevisan (2009), que serão descritos posteriormente.…”