Bearfoil and Turbine D
Thanks for your explanations. Those both make sense, though now I have another novice question.
When a turbine is windmilling on the ground, you hear a clicking noise. I am given to understand that this is from fan blades having some play (wide tolerances) built into their installation. I thought that design feature was to allow the blades to be flush against the outside circumference of the fan shroud or duct (for want of a better term). What's to keep the fan blade tips from overheating or wearing down at a rapid rate?