Patent ID: 7740483

Claim:
A method of demonstrating friction or power loss characteristics of different fluids utilizing a portable demonstration apparatus having different fluid chambers for receiving samples of the different fluids, comprising the steps of placing samples of the different fluids in the different chambers, establishing friction or power loss characteristics of the different fluid samples within the different chambers, comparing the friction or power loss characteristics of the different fluid samples, and displaying comparison data of said friction or power loss characteristics of the different fluid samples; wherein the friction or power loss characteristics of each fluid sample is established by using piston actuated friction shoes applying substantially the same friction or force at different times to different portions of a rotating test shaft while immersed in the different fluid samples and driven by a drive shaft of an electric drive motor at a substantially constant speed, and comparing, for the different fluid samples, an additional amount of current drawn or power absorbed by the drive motor or strain induced in the drive shaft during application of the friction or force to the different portions of said test shaft.