Optical Methods for Data Processing in Heat and Fluid Flow

Section 5 Multi-phase flow analysis

18

Recognition of Two-phase Flow Patterns with the use of Dynamic Image Analysis

R Ulbrich, M Krótkiewicz, N Szmolke, S Anweiler, M Masiukiewicz, and D Zając

Abstract

For many years interest in multiphase flow has been increasing in heat science and flow mechanics. Multiphase flow appears in many technique domains. It is a very common phenomenon in chemical, agricultural, food, cooling and power industries, and environmental or processing engineering. The techniques described here are as valid in gas–liquid as in gas–solid flow. The recognition of two-phase flow patterns is essential in process engineering. This kind of flow pattern is the most important criterion that enables correct calculation of processes of the heat and mass transfer. Researches of fluidization are very significant from the practical point of view, because they enable, for example, minimization of energy consumption in pneumatic transport or of selection and keeping proper parameters in fluidic power boilers.

18.1 Introduction

For the proper running of most apparatus, in which two-phase flow appears, generation of strictly specified two-phase flow pattern is required. Investigation of the process in industrial conditions requires the use of an objective method of identification, which is based on measurable features, which are characteristic for the specified two-phase flow. As far as single-phase flow is concerned, definition of distribution of velocity is enough but in ...