Talk:Heat exchanger

Latest comment: 6 years ago by InternetArchiveBot in topic External links modified

How does a Heat Exchanger differ from a Calorifier? Can someone clarify?

What is a Calorifier? Are you talking about a heater?

Turbulence due to baffles

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It states: "Having baffles spaced too closely causes the fluid to flow in a turbulent manner which is does not allow for effective heat transfer." Turbulence is generally the preferred flow state since it increases overall convective heat transfer. The disadvantage of having baffles too close would be a greater pressure drop (due to flow redirection), NOT turbulent flow. --173.30.154.225 (talk) 01:56, 3 May 2009 (UTC)Reply

References

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I´ve been doing some search for information in this subject and found a couple of available textbooks on the internet that will surely be usefull for expanding and also refining the concepts of heat transfer.

Please look at:

A Heat Transfer Textbook, John H. Lienhard V, Professor, Massachusetts Institute of Technology.

Wolverine Engineering Data Book II, Dr. K.J. Bell and A.C. Mueller: (Link no longer works)

Wolverine Engineering Data Book III, Pr. John R. Thome: (Link no longer works)

Please comment what you think. WiKimik 19:53, 6 September 2006 (UTC)Reply

Lienhard's book is an excellent reference. It covers a broad range of topics and is aimed at undergraduate engineering as well as general use for practicing engineers. Tjcognata (talk) 00:51, 31 March 2008 (UTC)Reply

chilled beams

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Chilled beams are a type of heat exchanger very popular in Europe and gaining acceptance in USA. A major manufacturer is TROX. See website http://www.troxuk.co.uk/uk/products/air_water_systems/chilled_beams/index.php

ASHRAE has started discussion in this area, but I can't find any major articles. A red link to this topic would help to encourage an expert to post information in this area. —The preceding unsigned comment was added by Hank1639 (talkcontribs) 18:12, 8 December 2006 (UTC).Reply

Properties of Oil

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I am building a system which uses oil for the primary heating fluid. My question is: When the oil is heated in an inclosed system, will the oil rise-flow towards the colder fluid not yet heated-without pushing it with a pump? Water will flow on it's own when heated without pumping it, but will oil react the same way? 83.44.57.28 13:48, 26 March 2007 (UTC)Reply

Please see Thermosiphon.
The way these systems operate is via a thermally induced density gradient. Every fluid I am aware of changes density when temperature changes, so you will induce flow in oil by adding or removing heat. You might consult NIST chemistry web-book Thermophysical Properties for fluid specific info.Tjcognata (talk) 01:41, 31 March 2008 (UTC)Reply

We used to call it Natural Circulation (vs Forced Circulation => pushing the fluid thru a pipe,or Forced Induction => pulling it thru). NC is used in many situations, including for emergency cooling systems of nuclear reactor plants (needs no power to operate). NC is driven by diferrential gravitational forces acting on two columns of the same liquid in hydraulic communication with each other but are at different temperatures. All piping should be slanted upwards towards the heat sink and fro, the heat source with no up-down jogs in the pipe that aould stop the circualtion. As differential temperature/density increases between the two columns of liquid, flow will increase. Flow stops when differential temperature dissapears. —Preceding unsigned comment added by Squeezmo (talkcontribs) 00:27, 21 December 2008 (UTC)Reply

Direct vs Indirect Heat Exchangers

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Not all heat exchangers have a physical separation between the working fluids. The ones that do are Indirect Heat Exchangers. The working fluids in Heat exchangers such as HVAC Coooling Towers and Low Total Gas Water Day Storage Tanks that hold water at around 200 degrees F to minimize gas absorption touch each other (no boundary), although in different physical states (watwer steam/vapor transferring heat between liquid water). When the working fluids in a heat exchanger contact each other, vide this is known as a direct heat exchanger. Direct heat exchangers deal heavily in latent heat since that is the primary source and sink of the heat being exchanged. —Preceding unsigned comment added by Squeezmo (talkcontribs) 00:35, 21 December 2008 (UTC)Reply

Flow arrangement terminology

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The terminology used in the "Flow arrangment" section seems confusing. It introduces the term "counter-flow" heat exchangers, then goes on to discuss concepts further and uses the term "countercurrent". I'm guessing they are synonyms, it would probably help if one were used consistantly. Is there a preferred term? Burt Harris (talk) 12:13, 11 April 2009 (UTC) there are various types of flow arrangement as parallel flow ,counter current flow. in parallel flow hot and cold fluid flow in the same direction while in case of counter current flow hot and cold fluids flow in opposite direction. — Preceding unsigned comment added by 121.52.147.68 (talk) 06:23, 27 September 2014 (UTC)Reply

Tube Crack

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I want to somebody anwser my question. What the probability tube expansion crack after we follow the right spec and creteria which mean the material and pressure in accepted condition? Number of tube 600 and we detect 2 crack. -Denny —Preceding unsigned comment added by 58.26.161.2 (talk) 05:52, 13 May 2009 (UTC)Reply

Reply-- Wikipedia is an encyclopedia, not a help site. You might be better off finding an industry expert.

Flow rate

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I was wondering what the consequences of changing the flow rate on either side (process or medium) would have. Getting the fluid to flow in a turbulent manner (rather than laminar flow) seems to be in conflict with getting a larger residence time. I've been reading a text that is all about controlling the heat exchanger with changing flow rates, but it seems that utilising a bypass is the way to go. —Preceding unsigned comment added by 116.212.198.34 (talk) 02:02, 9 July 2009 (UTC)Reply

The rate of energy transfer is proportional to the temperature difference. Longer residence times mean smaller temperature differences, because the fluids are allowed to equilibrate their temperatures more completely. The smaller the residence time, the greater the temperature differences and the greater the energy transfer rate. In other words, the faster the flow the better. If the flow becomes turbulent, then even better, because the transfer is the result of the temperature differences at the point of contact. In laminar flow, there will be a temperature gradient as you move away from the point of contact, and it will be such that the temperature difference at the point of contact will be lower than any other two points you pick (that are on opposite sides of the contact point). In turbulent flow, the gradient is lessened, and the temperature difference will be greater at the point of contact, causing a greater energy transfer rate. The goal is not to maximize the change in temperature as the fluid flows through the exchanger, it is to maximize the rate of energy transfer, which is not the same thing. PAR (talk) 13:39, 13 July 2010 (UTC)Reply

Vectorisation of 'Delta T 1.png'

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I propose that a vector (svg) copy of the above named file be used. The image is on Commons, so I don't know about adding {{ShouldBeSVG|graph}}. I would be able to create such a file using Inkscape, but not pure SVG from notepad (as indicated on WP:Collaboration_to_convert_graphs_to_SVG). -Jdedmond (talk) 08:11, 12 July 2010 (UTC)Reply

== LEGAMENT IS WHAT ? please somebody tell me what is leagament is heat exchangers ????

WHAT IS LEAGAMENT IN HEAT EXCHANGERS????

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PLEASE SOMEBODY TELL ME WHAT IS LEAGAMENT IN HEAT EXCHANGERS??? — Preceding unsigned comment added by 119.154.8.31 (talk) 05:35, 29 May 2011 (UTC)Reply

Vortex heat exchanger

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Can anybody comment on the tons of material on the web about Vortex heat exchangers? Is it a hoax or scam? Is there something of substance behind the idea? פשוט pashute ♫ (talk) 10:15, 14 July 2011 (UTC)Reply

Countercurrent exchange conservation circuit

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Countercurrent exchange conservation circuit

Is there an error in this figure? Why does the flow cool from 20 to 19 as it goes through the U-turn? The leftmost red arrows imply that heat is being added at that point. Maybe the vertical flow was supposed to be colder than u-turn flow. Spiel496 (talk) 23:42, 6 March 2012 (UTC)Reply

You are absolutely right, this needs to be removed and replaced, the current image is thermodynamically impossible. Would suggest going to the linked Countercurrent exchange in biological systems and adding the new image they have for a quick fix. The image would make more sense if the vertical flow was a lower temperature then the u-turn flow. Cstewwy (talk) 18:42, 11 November 2016 (UTC)Reply

Tubular Exchanger Manufacturers Association

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Interesting that there is no article on Wikipedia for TEMA. I'll try to start one. SChalice 04:03, 5 April 2012 (UTC)Reply

Here is a hack of a .pdf for a start /TEMA - SChalice 04:11, 5 April 2012 (UTC)Reply

EAD Saunders 1924 - 1997

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E.A.D.Saunders (1988). Heat Exchangers:Selection Design And Construction Longman Scientific and Technical ISBN 0-582-49491-5

"Ted" Saunders died in 1997. Much missed by everyone. Nice to see his book is still read. I have a copy of his original. — Preceding unsigned comment added by 92.29.252.101 (talk) 21:09, 25 August 2013 (UTC)Reply

Heating coil

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I believe heating coils warrant separate articles, namely on air coils and immersion coils.--عبد المؤمن (talk) 05:46, 9 July 2014 (UTC)Reply

spiral hx

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Should the spiral hx be listed in the types of hxs section? --Loins5 (talk) 02:44, 12 February 2015 (UTC)Reply

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I have just modified 4 external links on Heat exchanger. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:

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