Show Streamlined Mines Ines Suggested to Lower Lover over Ventilation Losses C Cincinnati i n c i inn n n a t ti i. i Streamlined mines using the discoveries of air flow which have produced the modern modern s sleek eek airplane i plane I were suggested here nere at the annual annual annual an an- nual coal mining convention by Prof H. H Landsberg of the Pennsylvania State college Ventilation losses when mine air has to turn an acute angled corner are equivalent to feet of straight lined concrete-lined tunnel he disclosed A right angle bend in a shaft creates creates creates cre cre- ates losses equal to feet of the standard reference lined concrete-lined tunnel A rounded bend by contrast produces losses equal only to about 25 feet of straight lined tunnel admitting that few mines can achieve the ideal of a smooth concrete lining Professor Landsberg Landsberg Landsberg Lands- Lands berg showed that it was possible to place the timbering so that much loss could be prevented Even mine cars achieve some streamlining Professor Landsberg indicated although they move relatively relatively relatively rela rela- slowly in relation to the ground Actually of course their velocity velocity velocity ve ve- relative to the ventilating airstream airstream air airstream stream when heading into it is the important point Studies showed snowed disclosed the professor professor professor pro pro- fessor that when a mine car blocks 20 per cent of a tunnel area a train of 20 such cars causes losses equal to feet of surface in the standard standard standard stand stand- ard smooth reference tunnel It uIt is true said Dr Landsberg in summary that one rounded corner corner corner cor cor- ner in a mine mino will wiIl not reduce the operating ng costs of a ventilating system appreciably but the sum total total total to to- tal of bends splits and overcasts along an air course of several miles will show the savings effected by bya a streamlined ventilation system |