In this paper, the effect of nozzle exit velocities on the transition point between zone 3 and zone 4 (as defined in the ASHRAE Handbook) was studied for a nozzle (D = 41 mm) with different outlet velocities. Combined with the results reevaluated from Nottage (1951) and Malmström et al. (1992), the measurement results show that for air jets with U_o < 10 m/s, the end centerline velocities of zone 3 could be proportional to the outlet velocities. For air jets with U_o > 10 m/s, the end centerline velocities are relatively constant, and this tendency seems to be independent of the outlet size. Some measurement results for zone 4 are also presented.

Units: SI