Michael Askin wrote: > On Fri, Jan 9, 2009 at 10:19 AM, Andy Greener <[email protected]> > wrote: >> Hmm, kinetic energy -> heat - this gets better! So the area of clear >> water below the lock has a relationship to the potential energy >> 'stored' in the pound above and the leakiness of the gates :-) > > Remember that the ice is just on the surface where the cold air can > get at it. The average temp of a section of a canal is actually much > above freezing, and so stirring of the water through either boats, or > drops in level, or through flow will reduce the ice. Where the flow is > great enough, i.e. rivers and narrow sections, it may take much lower > temps to create ice. > > Other structures around the canal, bridges, high walls (i.e. lock > walls), and even trees can increase the air temp and reduce the air > flow thus reducing ice formation. > > Heat created by conversion from kinetic energy would be quite small on > the scales we are talking about I would guess. > > I'm sure a scientist will be along soon with more thermodynamics :-)
Oh, yes....? :-) I'm not that sure... And I'm not going to wade through Perry's to find out. I would suggest... water failing - maybe a bit of heat gained by kinetic energy, and a load lost by turbulance and thereby mixing with air, and there will be some spray and we get enhanced evaporation. So I would plump for overall cooling. Ron Jones Process Safety & Development Specialist Don't repeat history, unreported chemical lab/plant near misses at http://www.crhf.org.uk Only two things are certain: The universe and human stupidity; and I'm not certain about the universe. ~ Albert Einstein
