Draft is one of the most common complaints in the indoor environment. It may be caused by convective air currents along windows and other cold surfaces providing air movement in the occupied zone of heated spaces.

The present paper comprises measurements of airflow characteristics (mean velocity, turbulence intensity, energy spectra of the velocity fluctuations, etc.) in a wide range of spaces in the field with different heating systems and without mechanical ventilation, The mean velocity and turbulence intensity in the occupied zone were lower than in mechanically ventilated spaces. The turbulence energy spectra were similar to those in a fully developed turbulent flow with the major part of the turbulent energy concentrated in the low-wave number range less than 5 m^-1. The highest velocity was measured close to the floor in rooms with a large window area and no heat source under the window.

Units: SI