Luftblanding

Luftblanding refers to the process of achieving a uniform distribution of air properties—such as composition, temperature, and humidity—in a space or system. It involves blending air from different zones or streams to reduce gradients and ensure consistent conditions throughout the volume.

In building services, luftblanding is a central concept in mixing ventilation. The goal is for supply air to thoroughly mix with room air, diluting contaminants, balancing temperature, and preventing stratification. Proper mixing can reduce drafts and hotspots and contribute to stable indoor air quality. Design considerations include the placement of diffusers and returns, air change rates, and the avoidance of short-circuiting between supply and exhaust paths.

In industrial and process contexts, luftblanding describes mixing of air with other gases or vapors as part of combustion, oxidation, or chemical reactions. Mixing devices such as jet diffusers, fans, eductors, or mixing chambers create turbulent flows that homogenize the gas mixture and improve mass transfer. The effectiveness of mixing is typically evaluated with tracer gas tests, sensor arrays, or other uniformity measurements throughout the vessel or ductwork.

Principles underlying luftblanding involve turbulent diffusion and buoyancy-driven mixing. Factors such as flow rate, geometry, and Reynolds number influence mixing efficiency and time. In practice, engineers aim to achieve sufficient mixing to meet performance or safety requirements while balancing energy use and comfort.

Regulatory and standards contexts for luftblanding include indoor air quality guidelines and ventilation standards that specify minimum air change rates, acceptable stratification, and, in controlled environments, criteria for uniformity of composition and temperature.