Hui Hu, the Martin C. Jischke Professor of Aerospace Engineering at Iowa State University, has studied icing of wind turbine blades for years.

Here's a news release from the arhives about his work:

Here's some data/information about his studies:

And here's a recent paper in the journal Renewable Energy about field studies of wind turbine icing:

Here's more information about Hu:

He is generally available by phone or email.