The arcuate shape of the trough bottom results in an effect similar to an airfoil effect, whereby the aspirated air is accelerated with the consequent beneficial effect on the gathering of the fibre fleece to {HEAD ~ the shape} of {TAIL ~ a fibre sliver} 
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The arcuate shape of the trough bottom results in an effect similar to an airfoil effect , whereby the aspirated air is accelerated with the consequent beneficial effect on the gathering of the fibre fleece to { HEAD ~ the shape } of { TAIL ~ a fibre sliver }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL