Introduction Page
Apparatus Page
Experimental Procedure
Perform Experiment

Introduction

Heat exchangers are involved in heat transfer, one of the most common industrial transfer processes. In all industries liquid or vapour streams routinely need to be heated and/or cooled; this operation is typically performed by heat exchangers. These heat exchangers may form part of the production process or may be used for heat recovery from waste streams. Heat exchangers can go under many names such as boilers, pasteurisers, air heaters, jacketed vessels, condensers, evaporators and so on. .

SHELL AND TUBE heat exchangers are the most common type used in the Chemical and Process Industries and are found throughout all processes from steam generation to refrigeration and at various points in production process.

In this experiment you will become familiar with the operation of a laboratory scale shell and tube heat exchanger. By varying the operating parameters and recording the resulting inlet and outlet temperatures you can determine rates of heat flow for each stream as well as the overall heat transfer coefficients for this particular heat exchanger.

Theory

Heat Flow in each stream:

-q -----=----- FlowRate -X -Cp-- X-- DT

kW------------ kg/sec-------kJ/kg------°C

Cp = 4180 J/kg for water (used in this experiment)

 

Heat Balance (assuming no losses):

q(shell) = q (tube)

 

Overall Heat Transfer Coefficient (U):

q(overall) = U A DTLM

Where:

U is the overall Heat transfer Coefficient for the Heat Exchanger

A is the surface area available for heat exchange

DTLM is the log mean temperature difference

q(overall) = q(shell) = q (tube)