2.?Experimental Facility2.1. Wind Tunnel and Scale Model BuildingThe experiments were performed in a wind tunnel located in the Air Physics selleck compound Lab, Aarhus University, using a model building. Figure 1 shows an experimental setup in the wind tunnel. The wind tunnel has double sidewalls and the ceiling surface was removed at the working section. The working section had a dimension of 6.00 m (length) �� 1.38 m (width) �� 1.55 m (height). 107 wooden blocks with dimensions of 50 mm �� 50 mm �� 50 mm and 25 mm �� 50 mm �� 50 mm respectively, were placed in the front of the working section with a distance Inhibitors,Modulators,Libraries of 100 mm apart in between to create an amount of roughness on the floor and to make the velocity profile at the working section similar to the natural wind over agricultural fields.
The resulting reference wind velocity at 0.5 m high above the floor was equal to 3.2 m/s. and the wind profile can be described in [10]:v=(3.46��0.02)h0.17��0.004(R2=0.97)(1)where, v, air velocity, m/s and h, height Inhibitors,Modulators,Libraries measured from the floor, m.Figure 1.(a) Layout of sampling positions for measuring the indoor tracer gas concentration at the cross-section plane of the scaled building. (��) represent the sampling positions and 1�C18 are labels of the positions, and the arrows indicate the …A 1:25 scale model building was represented as a sub-section of the stand-alone livestock building. The dimension and layout of the scale model building in the wind tunnel are shown in Figure 1. The roof and wall of the model building were made of a 5 mm thick clear acrylic sheet.
The external dimensions of the models were 500 mm in length and 550 mm in width, and ridge height 260 mm. The sidewall under the eave was 130 mm high, and the resulting fully opening size was 100 mm. The roof slope was 25�� and volume of the Inhibitors,Modulators,Libraries building Inhibitors,Modulators,Libraries was 0.11 m3. The internal space of the model building had the width of 270 mm, height GSK-3 of 240 mm and side eave height of 110 mm.2.2. Tracer Gas Release and Measurement TechniqueIn order to measure the ventilation rate through the ventilated scale model building, the tracer gas constant injection method [11,12] was adopted in this study. The constant method was often used when the ventilation rate remained constant during the measurement period, similar as this study. In the beginning, the injection volume flow of tracer gas was injected to the measured building space at a constant, q(m3/s).
After the steady state of the indoor concentration field has been reached, concentration differences between the indoor and outdoor, (Ci ? Co), were monitored simultaneously. The ventilation rate Q (m3/s) was then calculated by Equation sellekchem (2):Q=q/(Ci?Co)=q/(C?Co)(2)In this study, C is the dimensionless gas concentration, which is defined as:C=(Ci?Co)/Co(3)where, Ci, Co is the measured indoor and the outdoor concentration, respectively.Setup of the tracer gas experiment is shown in Figure 1.