Investigation of irregularity of flow distribution across the tube bundle in shell-and-tube heat exchanger with segmental baffles using PIV method

Grzegorz Ligus,Szymon Kołodziej

doi:10.1051/e3sconf/20171901005

Abstract

This paper presents the results of an experimental study into flow through a tube bundle applied in shell-and-tube heat exchanger with segmental baffles built on an industrial scale. The reported research applied Digital Particle Image Velocimetry (PIV) technique. The study offered the determination of the velocity vector fields, which were subsequently used for identification and measurement of irregularity of flow distribution across the tube bundle. Differences in the intensity of local flow velocities in shell side were identified by velocity profiles analysis. Furthermore correlation between the map of local velocity and its location in particular tube rows was described. As a result, the three main regions of flow velocity variation throughout cross-section of the shell side were identified.

Highlights

Among the equipment applied for heat exchange, shelland-tube heat exchangers hold an established position in the industry
The study of the hydrodynamics of the liquid flow through a tube bundle of a heat exchanger with segmental baffles confirmed the effectiveness of the application of Digital Particle Image Velocimetry (PIV) technique applied for the diagnostics of this type of apparatus
In order to carry out a complete assessment of the velocity vector fields across tube bundle, the investigation should be conducted on a simplified model of heat exchanger with a tube bundle ending directly behind the laser sheet

Summary

Introduction

Among the equipment applied for heat exchange, shelland-tube heat exchangers hold an established position in the industry. The shell side region is occupied by various type of baffles, which are applied with the objective of increasing the efficiency of the heat transfer in the shell-and-tube heat exchangers. The basic types of baffles including segmental, grid, disk, helicoidal and others differ in terms of the hydrodynamic characteristics, practical application and the cost of production Among these types of baffles, the considerable applicability coupled with the high increase of the heat exchange coefficient can be achieved due to the application of segmental baffles [1]. The only problems associated with their application are associated with the considerable pressure drop resulting from the disturbance generated by the flow through the shell side region [4,5] This directly affects the increase of the exploitation cost of the heat exchangers. This statement definitely finds an application in the case of shell side of a heat exchanger discussed in this paper

Measurement setup and methodology

Results and discussion

Conclusions