Experimental and Numerical Investigation of an Offset Jet Using Tangential Air Distribution System

Abstract

In this paper an offset, attached jet is investigated both experimentally and numerically, applying the tangential room air distribution system. The attachment distance of the injected air jet, which influences the ventilation characteristics in the room, is investigated as a function of the inlet Reynolds-number. Results showed that the attachment distance is independent from the inlet Reynolds- number in the range of Re₀ = 2 ÷ 4 * 10³ with fixed boundary conditions in a room.

In the past decades several researchers have investigated offset jets. However, the tangential room air distribution as a type of comfort ventilation and lower Reynolds numbers have not been considered.

Air velocity magnitude was measured in the injected air jet by a hot-wire anemometer. Three turbulence models were applied for the 3D numerical simulation: standard, RNG k–ε and SST k–ω models. In the present work the SST k–ω model seemed to be the most accurate turbulence model. The numerical results showed a high similarity with the measured data.