Abstract & Overview
Two-phase flow is important in an increasing number of applications and industries. For example, the safety analysis codes for the nuclear energy industry require closure relations for the vapor-liquid interfacial transfer terms, while accurate two-phase pressure drop models are necessary to design the piping systems in the oil and gas industry. Also, two-phase flow occurs in heat exchangers, steam generators, chemical reactors, oil transportation and many other process equipments. In addition, development of accurate and suitable instrumentations for on-line monitoring and measurement of the solids concentration and velocity in gas-solid two-phase flows has proven to be a challenging problem with many scientists and engineers worldwide developing novel techniques for this application. This paper presents a review on the electrical-based measurement techniques for gas-solid and gas-liquid two-phase flows along with the most recent patents developed for two-phase flow measurements. Also, development of a novel method for the design of capacitance sensors for void fraction measurement and flow pattern identification was presented in detail. Keywords: void fraction, recent patents, capacitance sensor, novel design method, gas-liquid flow, gas-solid flow, Two-phase flow