| That desk in front of you and everything else | | | | move the air. This method of heat transfer is |
| around you is made up of atoms. An atom | | | | called convection. Eventually all the air inside the |
| consists of electrons orbiting around a nucleus. An | | | | computer case will get hot, so fans are used to |
| atom is increadibly tiny. You could line up 10 million | | | | blow the air out of the case of the computer.The |
| of them inside a millimeter. What if we could scale | | | | heat has moved from the CPU, to the heat sink, |
| up an atom so that the nucleus was the size of a | | | | to the air inside the case, to the air in the room |
| basketball? The orbits of its electrons would then | | | | where you're sitting at your computer desk. The |
| be 15 miles away.From this you can understand | | | | room starts to get hot, and eventually the air |
| that atoms are almost all empty space. The | | | | conditioner turns on.You can view an air |
| nucleus of the atom is composed of quarks. If | | | | conditioner as a "pipe". A fan blows the hot air |
| you could see a quark or an electron up close, it | | | | from your room through fins that transfer the |
| might appear as a tiny vibrating glow of energy. It | | | | heat to a liquid. The liquid is piped to fins outside |
| turns out this world, which is causing us so many | | | | the house. A fan blows cooler outside air past the |
| problems and so much stress, is mostly an | | | | fins to remove the heat from the liquid.The air |
| illusion!The electrons orbit the nucleus at about the | | | | conditioner has an evaporator valve that changes |
| speed of light. If you could see them, they might | | | | the liquid to a gas after the heat is removed. In a |
| appear as a blur. They do not orbit in a plane like | | | | gas, the molecules are further apart than in a |
| the pictures in books. They create a shell. | | | | liquid. This causes it to cool down quite a bit more. |
| Sometimes two or more atoms will share | | | | The gas goes through the fins inside the house, |
| electrons, causing them to link together forming a | | | | picking up heat. It is then compressed into a liquid |
| molecule.Looking at that desk in front of you | | | | to concentrate the heat so the outside fins can |
| again, it looks pretty solid. Actually, unless your | | | | remove the heat more efficiently.Shuttle's I.C.E. |
| desk is floating in deep space where the | | | | (Integrated Cooling Engine) Heat Pipe uses a very |
| temperature is close to absolute zero, the | | | | similar method to cool a CPU. The CPU has a heat |
| molecules of your desk are vibrating like crazy. | | | | sink with copper heat pipes. The heat of the CPU |
| Picture the molecules bouncing around and | | | | causes liquid coolant inside the heat pipe to change |
| smacking into each other like balls on a pool | | | | to a gas. Convection created by the pressure of |
| table.If you have ever played pool, you're very | | | | the gas moves the coolant to a second heat sink |
| familiar with how when a pool ball hits another | | | | where a fan is used to blow the heat out of the |
| pool ball, it transfers it's energy to the second | | | | computer's case. Releasing the heat causes the |
| pool ball. When heat causes molecules to vibrate, | | | | coolant to change back to a liquid. Gravity then |
| they transfer energy between each other in a | | | | carries the coolant back to the CPU heat sink.One |
| similar fashion. This action is called | | | | last method of heat transfer we haven't |
| "conduction".Now picture the CPU of a computer | | | | discussed yet is radiation. Some of the heat of |
| cooking away because the designer wants to | | | | the CPU and the heat sink is released as infrared |
| push too much power through a small piece of | | | | radiation. Similar to light (although invisible to |
| silicon. If we don't take away that heat as fast as | | | | human eyes), the radiation strikes the insides of |
| it's created, that CPU will fry!The problem is | | | | the computer case, causing it to get warm. |
| usually solved by mounting a heat sink on the | | | | Ultimately the computer case itself acts as a heat |
| CPU. Conduction causes the heat to move from | | | | sink conducting heat to the outside air.This article |
| the hot CPU to the cooler heat sink. Because air | | | | explains the three ways - conduction, convection, |
| doesn't conduct heat as well as metal, We apply a | | | | and radiation - that heat is transported from a |
| thin layer of heat sink compound between the | | | | computer CPU to the air outside the computer |
| CPU and the heat sink to fill in any gaps.You'll | | | | case. You now understand the thermodynamics |
| notice that a heat sink has fins on it. The fins | | | | of a computers and why it is important to |
| allow the heat sink to conduct the heat to the air | | | | maintain its various components.Copyright(C) |
| adjacent to the fins. The fins provide more | | | | Bucaro TecHelp.Permission is granted for the |
| surface area to aid in conduction. Eventually the | | | | below article to forward, reprint, distribute, use |
| adjacent air will get as hot as the heat sink and | | | | for ezine, newsletter, website, offer as free |
| conduction will cease.If we move the air away | | | | bonus or part of a product for sale as long as no |
| from the heat sink, it will take the heat energy | | | | changes are made and the byline, copyright, and |
| with it. A fan mounted on the heat sink is used to | | | | the resource box below is included. |