Prior to construction of the Smith-Putnam wind turbine Palmer Putnam ordered wind tunnel tests of various blade designs and blade number in the wind tunnel at Stanford University. Here’s the first two paragraphs from the final report. This report contained charts, tables, and drawings.
Smith-Putnam Air Turbine
Conducted under the Supervision of
Elliott G. Reid
Guggenheim Aeronautic Laboratory
February 3, 1940
This report describes and presents the results of an investigation conducted in the Guggenheim Aeronautic Laboratory at Stanford University for the S. Morgan Smith Company of York, Pennsylvania. The experimental work consisted in determination of the aerodynamic characteristics of six adjustable-blade model windmills (Smith-Putnam Air Turbine). The wooden blades of all the models were also carefully measured in order that the degree of their conformity with design specifications might be available for the correlation of theory with experiment.
The results are presented in both tabular and graphical forms. Comments upon the accuracy of the models and upon the significance of certain of the results are appended. . .