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Thesis (M.S.)—University of Nebraska—Lincoln, 1958. Department of Agricultural Engineering.


Copyright 1958, the author. Used by permission.


The objective of this investigation is to determine the instantaneous tractive efficiency of a 12-38 pneumatic tractor tire while a tractor is exerting a drawbar pull on a concrete track. The computation of instantaneous tractive efficiency requires the instantaneous measurement of the input torque, the drawbar pull and the forward travel of the tractor.

The instantaneous wheel motion was recorded by two pens mounted 180 degrees from each other on the wheels. These pens described curtate cycloid curves from which data could be obtained for 90 degrees of wheel rotation.

Three tire inflation pressures were used: 16, 20, and 24 per square inch gauge, in combination with two different engine speeds.

Advisor: G. W. Steinbruegge