Fissore A, Nusgens P
Bibliographic info:
9th AIVC Conference "Effective ventilation" Gent, Belgium, 12-15 September 1988

An experimental study in reduced scale model for ventilation inside a sheep-fold has been studied. The ventilating system consist of two slots in opposite side walls and one in the roof, Two-dimensional jet are generated by the wind effect and temperature difference acting upon the sheep-fold. The jets generate several low pressure zones in the sheep-fold and these zones in term produce the deflection to the jet flow, The position of these zones in the space change dramatically even with a little variation of the thermal and dynamic boundary condition and therefore the movement of air in the space change due to this unstable phenomenon. The flow pattern, have been studied in function of different parameters such as Archimedes number, Reynolds number, flow rate for every inlet, velocity profile and turbulence in the inlet, situation of exhaust and length of the air inlet (slot ) in relation to length of the wall. It has been found that the main factors governing the air circulation are: relationships between the flow rates of the two inlets, relationship between the length of the slot and the length of the wall and the Archimedes number. However the mean velocity in the occupation zone is not very much affected by the above factors. In conclusion we estimate that this ventilation system by considering its low cost is suitable for this kinds of application. However, disadvantage may occur when a low pressure zone is formed between the inlet and the roof which could result a short-circuit in air flow.