I found this when looking for the correct airflow rate calculations of said machine after my own machines airpump wore WAY beyond spec. Since I wasn't going to fork out 1200euro for another heater I made a new case and vanes from graphite. The link below is pretty interesting and explains how said products are developed from the start and all along the way - the day job for some of us, but its an easy read and described well. http://gicl.cs.drexel.edu/index.php/Group_13_-_Kerosene_Heater Its also handy if your heater breaks down too lol Brian,
