Diffuser spacing simplified

An approach is suggested for simplifying the choice of correct spacing for ceiling diffusers. The method depends on satisfying an air change rate condition and a throw condition simultaneously. The air change rate condition is defined by the diffuser layout and ceiling height, expressed as a graph of diffuser spacing versus air flow per diffuser. The throw condition is the criterion for satisfactory air movement in the occupied space expressed as a relationship between throw and the distance to the next diffuser. It is envisaged that air change rate graphs could be drawn up for common diffuser layouts and ceiling heights. Diffuser throw data could then be made available as an overlay on transparent film so that the consequences of differing diffuser options would easily be ascertained by superposition of the throw condition onto graphs of constant air change rate.