Heat Exchanger

A Heat Exchanger is a device designed to efficiently transfer or exchange heat from one matter to another. When a fluid is used to transfer heat, the fluid could be a liquid, such as water or oil, or could be moving air.

Types of Heat Exchangers

  • Shell and tube heat exchanger

  • Plate heat exchanger

  • Plate and shell heat exchanger

  • Plate fin heat exchanger

 

The most effective type of Heat exchanger


Cross Flow Heat Exchanger. Counter Flow Heat Exchanger - Engineers Edge. Each of the three types of heat exchangers (Parallel, Cross and Counter Flow) has advantages and disadvantages. But of the three, the counter flow heat exchanger design is the most efficient when comparing heat transfer rate per unit surface area.

LMTD


The Logarithmic Mean Temperature Difference (also known as Log Mean Temperature Difference or simply by its initialism LMTD) is used to determine the temperature driving force for heat transfer in flow systems, most notably in heat exchangers. The larger the LMTD, the more heat is transferred.

 

Shell and Tube Heat Exchanger


This type of heat exchanger consists of a shell (a pressure vessel) with a bundle of tubes inside it. One fluid runs through inside the tubes, and another fluid flows over the tubes (through the shell) to transfer heat between the two fluids

Plate Type Heat Exchanger


A Plate Heat Exchanger is a type of heat exchanger that uses metal plates to transfer heat between two fluids. The concept behind a heat exchanger is the use of pipes or other containment vessels to heat or cool one fluid by transferring heat between it and another fluid.

Fouling Factor


The fouling factor represents the theoretical resistance to heat flow due to a build-up of a layer of dirt or other fouling substance on the tube surfaces of the heat exchanger, but they are often overstated by the end user in an attempt to minimise the frequency of cleaning.

Scaling Vs. Fouling


Scaling is a very different phenomenon from fouling. Scaling occurs when a mineral film coats the entire surface of a heat exchanger. The most common forms of scale are usually from calcium-based salts such as calcium sulphate or calcium carbonate.

 

Fin and Tube Heat Exchanger


Finned tube heat exchanger for heat transfer between air, gas and liquids or steam. The fin tube heat exchangers are designed to transfer heat from clean air and gases with high efficiency on liquids or vapors, and vice versa. In this way the media can be heated, cooled or condensed, in a closely space.

Compact Heat Exchanger
 

Compact heat exchangers are used in a great variety of applications. They allow for an increased heat transfer rate, require less volume and weigh less compared to other heat exchanger types. The disadvantage is the higher pressure drop.

Secondary Heat Exchanger


It removes the most amount of heat from the combustion flue gases. The primary heat exchanger is made of a specially coated steel tube system. Secondary condensing heat exchanger The secondary heat exchanger is unique to the condensing furnace

Tubular Heat Exchanger
 

Tubular heat exchangers can be subdivided into a number of categories, of which the shell and tube exchanger is the most common. A Shell and Tube Exchanger consists of a number of tubes mounted inside a cylindrical shell.

Air Cooled Heat Exchanger


Air Cooled Heat Exchanger's also known as Fin Fan heat exchangers are typically used in applications where water is not available or the desired process outlet temperature can be achieved given the maximum ambient temperatures. Air Cooled Heat Exchangers are used in a wide variety of applications

Types of Condenser


The three main types of condensers used in general refrigeration systems are

  • Air-cooled

  • Water-cooled

  • Evaporative

Fin Efficiency


The fin temperature effectiveness or fin efficiency is defined as the ratio of the actual heat transfer rate through the fin base divided by the maximum possible heat transfer rate through the fin base, which can be obtained if the entire fin is at base temperature i.e., its material thermal conductivity is infinite.