Leoben university optimises aircraft burners for hail defence

The Montanuniversität Leoben and Südflug Ges.m.b.H. have identified operating conditions that improve the performance of aircraft-mounted burners used in hail defence, ORF Steiermark reports.

The system burns acetone containing dissolved silver iodide and releases silver iodide particles into the updraft and downdraft zones of thunderclouds. The particles are intended to act as additional ice nuclei, encouraging the formation of more, smaller ice crystals.

Researchers at the university’s Chair of Thermal Process Engineering found that the optimal operating point produced about eight quintillion particles per kilogram of silver iodide. They assessed how particle production was affected by factors including the throttle position, acetone injection pressure and silver iodide concentration.