Melting rates of various size hailstones in a large vertical wind tunnel


  • Steven Newman
  • Narayan Gokhale


Cloud and Precipitation Microphysics


Artificially made, spherical hailstones of radius 0.50-1.75 cm were suspended in the updraft of a large vertical wind tunnel, and allowed to melt for time intervals of one to five minutes.  Until now, there have been no experimental results concerning  melting of large and medium sizedvhail. Calculations of mass  and radius melting rates were made for a one minute time  interval using the equations suggested by Macklin; however, the value of the heat transferc oefficient was recomputed.  Agreement between experimental and theoretical values was within five percent. In addition, melting profiles were calculated  for hailstones falling from various heights. A threshold radius of  0.69 cm for stones falling  from 5000 meters was found to agree well with the value of 0.73  cm calculated by Ludlam for stones falling from 5400 meters.




Technical Notes and Correspondence