Comparison between wind tunnel experiments and field measurement values on flow field in real Urban canyons

Abstract

Improvement of outdoor ventilated environment contributes notonlyto energy-saving and suppression of CO2 but also toindoorairqualityand itscomfort.Toconsider outdoor well-ventilatedenvironment, a flow field withinideal urbancanyons hasbeeninvestigated by wind tunnel experiment, but thebehaviorsof turbulence and mean characteristics ofcanyon vortices within real urbancanyons arestill not comprehended. In thisstudy, a wind tunnel experiment fora real apartmentcomplex wasconducted to confirm the reproducibility of flow field within the canyon. The apartment complex islocated at Musashino city,Tokyo, where fieldmeasurement was conducted.Thebuildings witha height more than two-stories were resolved within 200m radius under the modellength ratio of 1/150 was measured using both PIV (ParticleImageVelocimetry) and LDV (Laser Doppler Velocimeter). Thesemeasurements at5 points withinthe urban canyon werecompared with field measurement values. The wind velocities andturbulentintensitiesobtained by bothPIV and LDV fairly agreed withthe field measurement values withintheurban canyons, though a small-scale surface roughnesslike a balcony was notmodeled in the present wind tunnel experiment.