A heat pipe is a device that transfers heat using an evaporation-condensation cycle. It works by using a wick structure and working fluid inside a sealed container. Heat is absorbed at the evaporator section, causing the fluid to evaporate. The vapor travels along the container to the condenser section, where it condenses and releases heat. The condensate then returns to the evaporator via capillary action generated by the wick. Common materials for the container include copper, aluminum, and stainless steel. The wick is usually made of felt or metal foam and helps circulate the working fluid, such as water. Heat pipes can efficiently transfer heat over long distances and are used for electronics cooling and in aerospace

1. SUBMITTED BY:DEVNA RANI

2. What is a Heat Pipe?
 A heat pipe heat exchanger is a simple device which is
made use of to transfer heat from one location to
another, using an evaporation-condensation cycle.
 Heat pipes are referred to as the "superconductors" of
heat due to their fast transfer capability with low heat
loss.

3. Working Principle
 The heat input region of the heat pipe is called
evaporator, the cooling region is called condenser.
 In between the evaporator and condenser regions,
there may be an adiabatic region .

4. COMPONENTS OF HEAT PIPES
 Container
 Working fluid
 Wick or Capillary structure

5. Container
 Selection of the container material depends on
many factors. These are as follows:
 The function of the container is to isolate the working
fluid from the outside environment.
 Compatibility (both with working fluid and external
environment)
 Strength to weight ratio
 Thermal conductivity

6. CONTAINER MATERIALS
 The many materials available for the container, three
are by far the most common in use name copper,
aluminum, and stainless steel.
 While commercially pure copper tube is suitable, the
oxygen-free high conductivity type is preferable.
 Like aluminum and stainless steel, the material is
readily available and can be obtained in a wide variety
of diameters and wall thicknesses in its tubular form.

7. WORKING FLUID
The prime requirements are:
 compatibility with wick and wall material .
 Good thermal stability.
 vapor pressure not too high or low over the
operating temperature range .
 high latent heat .
 high thermal conductivity .
 low liquid and vapor viscosities.
 high surface tension.
 acceptable freezing or pour point.

8. WICK OR CAPILLARY STRUCTURE
 It is a porous structure made of materials like
steel,aluminium, nickel or copper in various ranges of
pore sizes.
 The prime purpose of the wick is to generate capillary
pressure to transport the working fluid from the
condenser to the evaporator.
 It must also be able to distribute the liquid around the
evaporator section to any area where heat is likely to be
received by the heat pipe.

9. CONTINUED….
 Wicks are fabricated using metal foams, and more
particularly felts, the latter being more frequently
used. By varying the pressure on the felt during
assembly, various pore sizes can be produce.
 The maximum capillary head generated by a wick
increases with decrease in pore size.
 The wick permeability increases with increasing pore
size.

10. Types of Heat Pipes
 Leading edge
 Rotating and revolving
 Flat Plate
 Micro heat pipes

11. Advantages Of Heat Pipes
 May reduce or eliminate the need fir reheat.
 Requires no mechanical or electrical input.
 Are virtually maintenance free.
 Provide lower operating costs.
 Last a very long time.
 Are environmentally safe.

12. Heat Pipe Applications
 Electronics cooling
 Aerospace
 Heat exchangers

13. REFERENCES
 www.heatpipe.com.
 www.cheresources.com.
 www.indek.com
 www.wikipedia.org

14. THANK YOU