õhuläbilaskvus

Õhuläbilaskvus, or air permeability, is a measure of the ease with which air can pass through a material or barrier. It is typically expressed in terms of air leakage rate, often in cubic meters per square meter per hour (m³/m²/h) or in terms of air changes per hour (ACH). Air permeability is an important property in various fields, including building science, materials science, and environmental engineering.

In building science, air permeability is a crucial factor in determining the energy efficiency of a structure. It affects the rate of heat loss or gain, as well as the infiltration of outdoor air pollutants indoors. Materials with high air permeability, such as porous bricks or open-cell foams, allow for greater air exchange but may also lead to increased energy losses. Conversely, materials with low air permeability, like dense concrete or closed-cell foams, provide better insulation but can trap moisture and promote condensation.

In materials science, air permeability is studied to understand the structural integrity and durability of materials. For example, the air permeability of textiles is important in determining their breathability and moisture-wicking properties. In environmental engineering, air permeability is considered when designing systems for air filtration and ventilation.

Air permeability can be tested using various methods, including the fan pressurization method, the air leakage test, and the cup method. These tests involve applying a pressure difference across a material and measuring the resulting air flow rate. The results provide valuable insights into the material's air permeability and its potential applications in different fields.