H EAT P IPE -T HERMAL E NERGY E XCHANGER -Maniks

I NTRODUCTION  Maniks Hear Pipe  What is Heat Pipe?  Actual working of a Heat Pipe  Types of Heat Pipes  Applications of Heat Pipes  Benefits of a Heat Pipe  Frequently Asked Questions

Maniks Heat Pipe

What is Heat Pipe? Heat pipe is a very efficient way to transfer thermal energy from one end to another. It works on the principles of thermal conductivity and phase transfer. The High thermal conductivity enables a heat pipe to transfer and dissipate heat to the desired location through a “capillary action”. This effect is similar to placing a paper tissue in a fluid and observes the fluid rise up the paper towel.Heat pipe Heat pipes were invented by Los Alamos National Laboratory in 1963 by George Grover to supply heat to and remove waste heat from energy conversion system.

Actual working of a Heat Pipe : A heat pipe is a copper tube with an internal wick structure that is sealed on both the ends with a small amount of water or ammonia liquid inside (Ammonia liquid is specifically used by Maniks). The wick is used to transport the liquid from one end to other. As heat is applied to the hotter side of a pipe, the water will boil and turn to a gas which then travels with the thermal energy to the colder end of the heat pipe where it condenses back to a liquid. This process is known as capillary action. This cycle is repeated continuously to remove heat from a system.Maniks

Types of Heat Pipes  Vapour chamber or flat heat pipes  Variable conductance heat pipe  Diode heat pipes  Thermosyphones  Loop heat pipes

Applications of Heat Pipes  Today, Heat pipes are used in a variety of applications from space to handheld devices that fit in your packet. Some applications are listed below  Spacecraft  Computer systems  Solar thermal  Permafrost cooling  Cooking appliances  Ventilations and heat recovery nuclear power conversation

Benefits of a Heat Pipe  High conductivity effective thermal  Transfers heat over long distance with minimal temperature drop.  Passive operation  No energy input is required to operate the heat pipe. There are no moving parts.  Long life with minimum maintenance  There is nothing in heat pipes that wear out heat pipes are passive. Since there are no moving parts the only maintenance recommended is periodic cleaning  Cost efficient  By lowering the operating temperature, these devices can increase the Mean Time between Failures for electronic assemblies. In turn this lowers the maintenance and replacement costs.  Flexible size

Frequently Asked Questions Are heat pipes reliable? -Yes, mainly because they have no moving parts. They are ideal for applications such as aerospace where maintenance is not feasible. The main cause of heat pipe failures is gas generation in the heat pipe, but this can be completely avoided by proper cleaning and assembly proceduresheat pipe Can heat pipes work against gravity? -Yes, this occurs whenever the evaporator is located above the condenser. In these applications the working fluid must be pumped against gravity back to the evaporator. This occurs through wick structures that pump working fluid through capillary pressure developed in the porous wick. The finer the pore radius of a wick structure, the higher against gravity the heat pipe can operate.