Three-dimensional model of air speed in the secondary zone of displacement ventilation jet

This paper presents a new three-dimensional model for the distribution of air speed in the secondary zone of a displacement ventilation jet, combining both physical analysis and correlations-based models. For this purpose the measurements on two wall-mounted DV diffusers are used along with other published data. The maximum air speed at the end of primary zone is predicted by using the supplying conditions at the outlet, the thickness of air jet at the end of the primary zone, and the air entrainment in the jet. The longitudinal profile of maximum air speed in secondary zone is modeled using a new normalization and a generalized profile developed using correlation-based models obtained from experimental data. The vertical and transversal air speed profiles are also presented and analyzed. Finally all air speed profiles in the secondary zone are combined into a three-dimensional air speed model in the DV jet.