Heat Flow Mechanics
HVAC systems! The familiar term “cold” refers to the absence of heat. At absolute “0” there is a complete absence of heat and atomic activity ceases. Heat, or energy, is produced by atomic activity. As a result of this scientific principle, heat will always flow to the cooler or colder area or object and stimulate atomic energy release in the colder subject.
Heat Flow and HVAC Systems Application
Cold air is heavier than warm air. Warm air rises as it is displaced by the cooler air. Therefore, the heat flow in a house is from the heated, lower levels of the structure, upward toward the ceiling. As it lingers at the ceiling it will eventually cool and fall to the lower levels to absorb heat and repeat the heating and cooling air flow cycle. This principle accounts for the air circulation pattern in a heated structure. At some point this exchange of warm and cool air will reach a state of essentially equilibrium (average out) and give a sensation of uniform warmth, assuming a heating unit of adequate capacity. This principle also applies to the summer cooling requirement. However, the delivery system for the cool air will most likely require a greater capacity due to the heavier cool air. Based on this principle, it is possible that a single source can supply the heating and/or cooling requirement for a whole house. Other principles of heat transfer will also be operational – conduction and convection.