In most flow meter installations it will be very difficult to ensure that the flow profile is fully developed.More often the flow profile will be distorted by a bend upstream or an area change due to a contraction,expansion or valve in the pipework.This profile distortion will also lead to additional flow losses.Due in part to its importance industrially, the flow in a bend has been quite extensively documented and the effects on flow meters have been measured.
Figure shows in diagrammatic form of the effect of bend on the flow profile.The higher velocity fluid at the centre of the pipe moves to the outside of the bend while the lower velocity fluid at the wall moves to the inside.The result at the outlet of the bend is shown by a lower velocity and a region of higher velocity.This profile will in most cases affect the registration of a flow meter which has calibrated on a fully developed flow profile.
Swirl reduction and velocity profile correction naturally in long lengths pipes due to diffusion and turbulent mixing.The new type of elbow conditioner uses correction tabs projecting from inner surface , generate vortices that accelerates these natural pipe effects to create uniform non swirling symmetrical flow profile in a much shorter section of the pipe.
Advantages
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Provides accurate and repeatable measurement
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Amount of area required for installations will be less
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Eliminates labour cost and pipe cost