Dynamic behaviour of a heat exchanger handling super-critical fluid
McCann Science
Click to McSc Home Page

Strange Behaviour
This little puzzle began with watching the response of a shell and tube heat exchanger in an experimental rig. We let the rig run for a while. Then we increased the cooling by dropping the shell side feed temperature quickly... we were looking for dynamic responses...but instead of the tube side exit temperature dropping, it went up.

Explanation
The exit temperature had been falling, so the pipe beyond the heat exchanger had a temperature profile in it which was rising away from the exit. When we increased the cooling, the material inside the tube of the exhanger shrank very rapidly because of the very big temperature coefficient of expansion of this super-critical fluid. As a result, some fluid which had already passed through the exchanger was drawn back in so the exit temperature indicated an increase.

What next
The result was that we had to rethink the way we modelled the heat-exchanger. Thinking in terms of a passing stream of fluid within it was not enough. It became necessary to track the state of the fluid and at all times, recognise its volume and hence the position of each elemental region beyond the heat-exchanger exit.

Your Problem?
Maybe you have a problem that involves the behaviour of strange materials with unusual properties. McCann can probably find a way to quantify its behaviour and give you a basis for rational design. Call any time or email to discuss the ideas, in confidence, of course. There's no charge for finding out if McCann can help.

Links in website:
Home/Index Page

About McSc
Summary
Principal (CV)
Contacting us
Contact in UK
Location USA
Philosophy
Software Tools
Fees
CAD service

Click to Applications PageApplications

Business & Commerce
TV Advertising
Drugs Competition
Housing Demand
Automobiles Demand
Wallcoverings Battle
Cash Flow
Human Resources
Project Management
Patent Analysis

Chemical Industry
Cooling Tower
Fermentation
Polymer Process
Heat exchange
Supercritical Fluid
Distributed parameter
Toxic gas allocation

Electrical
Control systems
Initiation systems
Ferrite Filters
Microstrip Antennas
Lightning

Production & Process
Automated manufacture
Crimp and Press
Glass making
Glass molding
Glass to metal seals
Heat exchanger
Helium Leak Testing
RF Soldering
Vacuum web coating

Click to Applications PageApplications.

Invitation. McCann can help if you have a design or operational problem that needs some technical support that is outside your team's experience, some quantitative assessment of what is really the cause of the difficulties, some design alternatives or just a fresh look by an intelligent interrogator.
If you have a problem with the behaviour of a market sector, plant, process or item of equipment and would like to get a quantitative handle on it to improve yield or optimise performance, then contact us. We are always ready to give a little time to discuss a new puzzle, in confidence, of course. We'll only worry about fees when we have some defined work. We can be flexible about how we work with you.
Top
McCann Science,
POB 902,
Chadds Ford PA
19317 USA.
T: 1 302 654-2953
F: 1 302 429 9458
E: mjmccann@iee.org
Request. Please let us know how you found this website and your interests by using the quick feedback form. Thank you Date: 2003.XX.XX
File: blankTable.htm