An orifice can be screwed into either of the threaded holes and the unused aperture sealed with the blanking plug provided. A scale is mounted on the side of the tank to enable the height of the water above either orifice position to be determined. This arrangement avoids excessive turbulence and enables a steady level surface to be maintained. Two threaded holes are cut into the tank in which to mount the orifice being studied, one in the tank base for 'vertical' discharge, and the other in the tank side for 'horizontal' discharge. The zero of the scale coincides with the centre of the side outlet position. The Orifice sets are used in conjunction with the Inlet Head Tank for the investigation of the flow of water through a horizontal or a vertical orifice. Water is supplied to the tank via a hose connection to the base inlet, and is then distributed within the tank by a vertical perforated sparge pipe. When an orifice is fitted in the horizontal discharge position a Trajectory Profile Hook Gauge can be used to determine the jet profile. Details of both sets of orifices are given as follows.
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