Heat Exchangers - Lab 4

Heat Transfer Lab

Fall 2006

Principle

Heat transfer between hot and cold fluid streams contained in either (a) simple tubular, (b) shell and tube or (c) plate type heat exchanger as a function of plates employed, stream flow rates, flow configuration and inlet temperature. The type of heat exchanger to be tested will be selected just prior to performing this experiment. One possibility will be to assign different types to different lab teams.

 

Object

Determine the outlet flow temperature by an energy balance, and the heat transfer coefficients by applying heat transfer correlations to the fluid flow properties. Log and plot data during steady state conditions. Model by applying the LMTD and effectiveness-NTU methods.

 

Background

Background, theory and computational methods are presented in Chapter 11 of the current Heat Transfer text, "Heat and Mass Transfer" by Çengel.

 

Apparatus

 

See attached data sheets for Armfield HT30XC series computer controlled Heat Exchanger Module and for the HT31, 32 and 33 Heat Exchangers. A laptop computer having the associated controlling and logging software will be made available to run this experiment and to log steady state temperature and flowrate data associated with each experiment setpoint.

Procedure

 

Configure the selected experiment in each allowable flow configuration. Keeping the temperature of the hot fluid fixed at 35 C, vary flow rate of each fluid and record (log to a disk file) steady state heating of the cool fluid.

 

 

 

Analysis

Analyze the logged data results based on an energy analysis. Compute the overall heat transfer coefficient, U, from the heat transfer coefficients determined from fluid properties using Nusselt, Reynold's and Prandtl numbers and appropriate correlations. Apply the LMTD, log mean temperature difference, and the effectiveness-NTU method in the analysis.

 

Document and Discuss

Photo document by digital photograpy. Make short video record with a webcam. A discussion list will be provided at experiment time for guidance in preparing the lab report.