Double Pipe Heat Exchanger & its Working Principles types

Heat Exchangers transfer or exchange heat between two fluids without mixing and come in various types depending on the design, application, required space, and fluid flows in the system. The heat exchangers have a barrier that separates the fluids and allows heat transfer simultaneously.

There are two types of counterflow or parallel flow for this type of pipe, which are the basis for determining pipe size, length, and the number of bends.

Heat exchangers with double pipes

In a double pipe heat exchanger, we have a large pipe with a small pipe inside it concentrically, and all the heat transfer occurs in the larger pipe. As a conductive barrier, a small pipe flows one fluid through its interior and another fluid flows between the inner and outer pipes. Outside or shell side fluid flow includes inner side fluid flow.

Specification and Applications

It was discussed before that the design of a double pipe heat exchanger is simple and modular, but if you increase the exchanger's surface area, you'll have to pay a lot more for it. Listed below are just a few: – Boilers and compressors, as they operate at high temperatures and pressures – Heating and cooling in process engineering – Refining petroleum – Treatment of sewage

Different types of double pipe heat exchangers

The direction of flow can be used to categorise double pipe heat exchangers. Parallel and counter flows can be deployed in these exchanges, and it all depends on where the inlets and outlets are positioned. Parallel and counter flow affect the heat transfer and pressure drop in the system, and, by the way, in some applications, you should choose one over the other.

The advantages of double pipe heat exchangers

– Providing good efficiency at lower capital costs is possible. – Compared to shell and tube, they are smaller and require less space for maintenance, while the heat transfer is acceptable. – They are very popular, so all the parts have been standardized, which makes repair and maintenance easier. – A flexible design allows them to be easily added to or removed. – High pressures and temperatures can be handled by this type of exchanger.

The disadvantages of double pipe heat exchangers

– These are usually used in counterflow designs and cannot be used in some applications. This does not mean that they cannot be used in parallel flow designs. – They are limited by heat transfer rather than complicated designs and should be used in low heat applications. – Leaking occurs more often in this type (with more units).