Influences of oil viscous-temperature property on transfer property of hydroviscous dynamometer

Hydroviscous dynamometer is a loading device of power machine testing. Early researches deduce torque of hydroviscous dynamometer by considering oil viscous as a fixed value. In this paper, oil flux inside the friction plates is seen as a gap flux, viscous temperature (abbr. V-T) relationship is considered being related to viscous-diameter (abbr. V-D) relationship. They are discussed together in order to deduce the alternation of load torque with variable viscous of the lubrication oil, temperature, and gap of the plates under liquid friction state. 2-D surface figures are used to show the V-T and V-D relationships for comparison. Conclusions are drawn that loading torque decreases with the increase of input-output oil temperature. Temperature has little influence in viscosity and torque when the temperature is over 50°C, while it has obvious influence under 50°C. Formulas that could be used to forecast torque variation are deduced out for developing better control strategy especially at low temperature.