- A heat exchanger is used to move heat from one place to another. What we call heat is actually energy. Hot things contain and emit more heat energy than cold things. This is due to the movement of the material's molecules and atoms. All matter is constantly vibrating on the atomic level. The faster the atoms are bouncing, the hotter the material is. The term absolute zero refers to the complete cessation of atomic particles. This would mean a material is so frozen that its atoms do not bounce off of each other. No material has ever been observed to reach absolute zero.
- The basic principle behind heat exchangers is the fact that heat energy wants to find equilibrium. Much the same way water seeks its own level, heat energy wants to transfer itself to less hot materials.
- For a simple example, make your own basic heat exchanger. Fill a glass with room temperature water. Now drop in an ice cube. As the ice melts, the water becomes colder. That's because the water is transferring its heat to the colder ice cube. After the ice cube and water reach the same temperature, the exchange of heat is over. If your glass of water is surrounded by warm air, the water will eventually become warm as it exchanges its heat with the air.
- Many types of heat exchangers are in use today: industrial, commercial, residential and even personal. Most heat exchangers use water because it is an excellent conductor of heat energy. A common system would involve two tanks of water. One tank for cold, one for hot. The water from each tank is pumped into a dual chambered reservoir. The two chambers are separated by a thin layer of highly conductive metal. The hot water will then transfer its heat energy through the metal wall into the cold water. The water is continually pumped through the system to maintain a steady exchange of heat.
