Heat Exchangers: Types & Applications

Heat exchangers play a vital role when chosen for different industries. However, there are different types of heat exchangers, and each is suitable for a different environment.

If you are looking forward to learning about heat exchangers, their types, applications, and essential design considerations, go through the guide below.

What is a Heat Exchanger?

A heat exchanger carries out the task of transferring heat. It is used for heating as well as cooling by transferring heat energy through conduction.

Heat exchangers allow temperature control in different environments and processes. It helps to prevent overheating and enhances efficiency and safety.

In the processes where heat is generated, the heat exchangers are meant to keep the process safe and utilize the heat energy in an efficient way.

Types of Heat Exchanger

The four different types of heat exchangers have their applications to cater based on their working mechanisms. These four types of heat exchangers are discussed below:

Double Tube Heat Exchanger

Double tube heat exchangers are equipped with a tube structure. It has two pipes which are installed within one another. When one fluid passes through the inner pipe, the second passes around the first one in the outer pipe.

This is an affordable, very simple heat exchanger. It has a small size and hence is suitable for limited space.

Shell and Tube Heat Exchangers

These heat exchangers offer high versatility. They have multiple tubes that are fixed within a cylindrical shell. The design of this heat exchanger helps to manage different levels of temperature and pressure.

Shell and tube heat exchangers are suitable for heating and cooling a large amount of gasses and fluids. They are easy to clean and repair.

Tube-in-Tube Heat Exchanger

As the name suggests, a tube-in-tube heat exchanger is a type of heat exchanger that has two tubes, and each tube is meant for each type of fluid. These tubes are joined together with the help of a coil to create a pattern.

It is a compact type of heat exchanger and is used in environments where high pressure and high temperature prevail. It offers to run at high output and hence offers high efficiency.

Plate Heat Exchangers

These heat exchangers consist of metal plates that help transfer heat that is present between the fluids. The plates have space inside, which allows the fluids to pass, and the surface area of the plates is high, ensuring better heat transfer.

These heat exchangers are highly expensive, but they offer high efficiency as well. Plate heat exchangers are used in power plants because they are highly durable and require fewer repairs.

What are the Thermodynamics of Heat Exchanger?

The working mechanism of a heat exchanger is dependent on the conservation of energy. This represents the 1st law of thermodynamics.

According to this law, the energy that enters and leaves the system must be equal. The heat exchangers work with the same concept as the energy is transferred between the fluids. The hot fluid energy is gained by the cold fluid.

The heat exchangers have different configurations, and the most common one is the counterflow. Counterflow flows the fluid in the opposite direction, whereas parallel flow moves the fluid in the same direction.

Counterflow offers a better thermodynamics design, which is efficient as a major temperature difference is present between fluids, and hence, the heat transfer is maximum. The parallel flow design, being simple, is less efficient because the difference between the fluids tends to decrease quickly.

Design Considerations

When designing heat exchangers, some of the factors to keep in mind are as follows:

Operational Parameters

When designing a heat exchanger, parameters like temperature ranges, pressure levels and sizes are very important to consider. The optimal temperature ensures thermal efficiency, whereas pressure levels ensure to prevent leakages.

The sizes and configurations of the heat exchangers manage the flow rate and deal with the related issues.

Material Choice

The heat exchangers must be manufactured using the right material. Material selection predicts high performance and durability. The material chosen for the heat exchanger is also evaluated for its corrosion resistance.

The exposure of heat exchangers to fluid and moisture must be taken into account, and high thermal conductivity is also crucial. Hence, the materials selected should be strong enough to withstand vibration and stress.

Properties of Fluids

The characteristics of fluid also impact the heat exchanger design. The phase changes like vaporization and condensation must be taken into consideration for heat exchangers.

The fluid’s flowing potential is very important to understand, and configurations must be chosen carefully so that the performance of the heat exchanger is maintained in the long run.

Flexibility of Operations

Heat exchangers are designed with operational flexibility in mind so that they can handle varying loads.

It helps to ensure that the turndown ratio is high. It even ensures that cleaning and maintenance are easy, keeping in mind the long-term life and reliability of the heat exchanger.

Applications of Heat Exchanger

Échangeurs de chaleur are used to carry out versatile applications, and some of these applications are as follows:

HVAC Systems

HVAC systems help transfer heat between indoor and outdoor air. They tend to maintain a very comfortable temperature in the spaces where these systems are installed. Hence, they offer energy efficiency and usability for the process of heating and cooling.

Power Generation Plants

En power plants, the role of the heat exchanger is to convert the heat energy into electricity. These are used in condensers, boilers, and cooling towers, which help manage the flow of heat and ensure optimal power production.

Industrie chimique

In the chemical industry, these heat exchangers offer better temperature control during chemical reactions. They are also used for condensing, cooling, and evaporating chemicals.

Oil and Gas Industry

In the oil and gas industry, heat exchangers help manage heat during purification, distillation, and oil processing.

Conclusion

DEK is one of the leading manufacturers of various components used in different industries. We even offer to cater to your projects with high-quality heat exchangers.

We deal in all types of heat exchangers and can also offer you our recommendations regarding your project requirements. So, get in touch with us and make the best use of heat exchangers designed by our skilled team.