What is the phenomenon of "stratification" observed in heating systems?

Stratification in heating systems refers to the layering of air at different temperatures. As warm air rises and cool air sinks due to the principles of convection, this results in distinct layers of air within a space. Warmer air, being less dense, accumulates near the ceiling, while cooler air remains closer to the floor. This phenomenon can affect the comfort level in a space and the efficiency of heating systems, as it may lead to uneven temperature distribution. Understanding stratification is crucial for optimizing heating strategies, ensuring that systems are designed to either promote mixing of air or to effectively deliver heat to lower levels where it is often needed most. This process distinctly contrasts with the other options, as it highlights the natural behavior of air in accordance with temperature differences, rather than focusing on efficiency or circulation patterns.