What is Heat exchanger: Definition and 168 Discussions
A heat exchanger is a system used to transfer heat between two or more fluids. Heat exchangers are used in both cooling and heating processes. The fluids may be separated by a solid wall to prevent mixing or they may be in direct contact. They are widely used in space heating, refrigeration, air conditioning, power stations, chemical plants, petrochemical plants, petroleum refineries, natural-gas processing, and sewage treatment. The classic example of a heat exchanger is found in an internal combustion engine in which a circulating fluid known as engine coolant flows through radiator coils and air flows past the coils, which cools the coolant and heats the incoming air. Another example is the heat sink, which is a passive heat exchanger that transfers the heat generated by an electronic or a mechanical device to a fluid medium, often air or a liquid coolant.
Homework Statement
What happens when in counter flow heat exchangers, you diminish the mass flow of the low temperature stream?
Homework Equations
UA = cte
m2 = cte
Tin = cte
tin = cte
Q=cm1(tout-tin)
Q=cm2(Tout-Tin)
Q=UA(Tout-tout)+(Tin-tin)
----------------------...
Hi,
I am trying to do a cross flow analysis in FLUENT. Air and water in a cross flow heat exchanger. The fluids do not come in contact. I have modeled and meshed the geometry in GAMBIT. Could someone pls help me with the steps in FLUENT as to how to assign different fluid properties for...
In a geothermal heat exchanger where well water is cerculated up from one well and down another [some distance away] where water treatment is certanly not premissable; what techniques are available to minimize mineral? build-up on the exchanger [tube] walls.
[1] I have heard of putting...
Window-type Aircon
how to get this in an actual experiment?
is it just (mass flow rate of the refrigerant X specific heat X Change in temp of the refrigerant)
or (mass flow rate of the air passing thru the heat exchanger X specific heat X Change in temp of the air)
or (mass flow rate of the...
Homework Statement
in practice is is assumed well insulated heat exchangers are adiabatic. With reference to this heat exchanger, carry out the necessary calculations and then give an opinion as to the validity of this assumption.
Homework Equations
Observation
Thotin 55.88, Thotmid...
Hi guys,
I've been on a few message boards looking for a solution to my problem, but no one has really been able to help me yet. Here is the problem:
Question===================
Hi all,
this is my first post/thread, just starting out as a second year chemical engineer and I seem to...
I've got a problem. I'm trying to design a reactor with internal cooling provided by water flowing through tubes directly within the reactor. Basically, it's like a shell and tube heat exchanger with an internal heat source.
The problem is that the cooling water is to be evaporated within...
We have this heat exchanger installed in our plant. There are two modules. In module-2 saturated steam is entering @200 Deg C and heating the air from 40 to 80 Deg C. Condensate from module-2 is given to module-1 which preheats the air entering in module-2 from ambient temp (30 Deg C) by 10 Deg...
I am working as an intern at a biodiesel plant and we are looking into setting up solar heating to reduce the amount of electricity we are using to heat up our oil during the various stages of the process. Of course, this is only one of many projects going on at the college, so the budget is...
I'm stuck with the final part of this question.
A heat exchanger consists of a bundle of steel tubes each of 25.4mm outside diameter and with a wall thickness of 3mm. Cooling water flows through the tubes with a Reynolds number of 10,000 and a mean temperature of 40'C. Scale deposited on the...
hi ever1,
im final year student doing my final year project at uni. It is basically finding justifications to many abnormal outcomes of the test. I was given 2 standard correlations for Nu and F and these are:
Nu=0.023 Re^-8 *Pr^(1/3)
Fr=0.064/Re^0.2
But when carring out the test I am...
Is there a way to chemically clean this type of exchanger from graphite impurities (tiny particles) ? is possible to chemically remove coke,soot,graphite at all? we clean it with xylene but that doesn't help
tnx
I am building an evaporative heat exchanger for my final project in a transport phenomena course in college. I am having difficulty in finding equations that I can either use or derive for my particular type of exchanger.
Does anyone have any ideas where I can find or derive equations to deal...
Hello!
In heat exchanger (U-type) I've problem with erosion/corrosion at beginning of tubes in heat exchanger,near tube-sheet where steam enters.i suspect cavitation is problem. on tubes there's a channel of erosion in the middle of tube where material is gone and tube is very thin in that...
Adiabatic heat exchanger problem... Please Help!
I have this proplem as a homework assignment and I'm a bit stuck as houw to set it up. Here it is:
Propane gas enters a continuous adiabatic heat exchanger at 40 degrees C and 250 kPa and exits at 240 degrees C. Superheated steam at 300...
Hello,
I have some problems in resolving this exercise.
Consider a cylindrical heat exchanger, whose you know all caracteristics (such as : inside diameter, outside diameter and its length). This exchanger is used to cool an oil phase with water.
We know the flow of water, its Cp and its...