Heat pipes are effective methods to move heat from one location to another within closed-loop systems. They are used as heat recovery systems, thermal control systems for spacecraft, and electronic-device cooling components. A heat pipe is a passive device that transmits heat using capillary action and the laws of thermodynamics. It is made up of a working fluid and a wick structure all contained within an otherwise evacuated tube. The tube’s material should have high thermal conductivity and the wick structure must move the working fluid from the cold end to the hot end of the heat pipe.

The fluid within a heat pipe needs to have a low boiling point and a high latent heat of vaporization. Copper piping is often paired with water and aluminum with ammonia. Heat pipes are common in HVAC systems, electronics, and aerospace vehicles. Some variables, including the wick structure, working fluid, and operating temperature, can impact how well heat pipes perform. This article will define heat pipes and outline the components, types, applications, and factors that affect their performance

What Is a Heat Pipe?

A heat pipe is a technology that uses the evaporation and condensation of a working fluid to move heat from one place to another. Heat pipes are usually used in spacecraft, electronics, and other fields where space, mass, or energy consumption are restricted.

What Is the Function of a Heat Pipe?

A heat pipe's main job is to efficiently transfer heat from a heat source to a heat sink. It can transfer a lot of heat even if the temperature difference is minimal because a phase change is part of the process. 

How Do Heat Pipes Work?

Every heat pipe needs a working fluid — usually water or a refrigerant. The fluid absorbs heat, vaporizes, and then moves to the cooler end of the pipe where it releases heat by condensing back into a liquid. This ongoing cycle enables it to transfer heat over considerable distances. Systems for electronic cooling and heat recovery tend to utilize heat pipes.

What Are the Components of a Heat Pipe?

The following parts make up a heat pipe:

1. Evaporator

The item in a heat pipe known as the evaporator is responsible for absorbing heat from the source and vaporizing the working fluid. The vaporized working fluid will then transfer heat from the source to the condenser.

2. Condenser

When the working fluid releases heat and condenses back into a liquid, it does so in the condenser section of the heat pipe which is in contact with the heat sink.

3. Wick Structure

The working fluid is typically transported from the cooler end of the heat pipe to the hotter end via capillary action with the aid of the wick structure that lines the interior walls of the heat pipe. Sintered metal powders, woven metal mesh, and porous ceramics are examples of typical wick materials.

What Does a Heat Pipe Look Like?

An example of a heat pipe is shown in Figure 1 below:

Heat Pipe: Definition, Components, Types, Applications, and Factors that Affect Its Performance