Fluid Dynamometer Having Fluid Characteristic Power Absorption Adjustment Capability.

A fluid dynamometer is provided for absorbing a range of power output produced by an engines rotating shaft. Power absorbing characteristics are controlled by adjusting the fluid media characteristics in terms of its temperature andor its density and viscosity. A tank, containing an energy or power absorbing fluid, receives the rotating shaft. One or more disks, submerged in the fluid and coaxially mounted on the rotating shaft for rotating therewith, cooperate with the fluid to absorb power from the rotating shaft. The disks are sized so that a first specified amount of power from the rotating shaft is absorbed at a calibration temperature of the fluid. Heating and cooling units are provided to respectively heat and cool the fluid. A controller energizes the heating and cooling units in a cooperative fashion to adjust and maintain the fluid at a predetermined temperature value for power absorption at a second specified amount of power produced by the rotating shaft. A fluid composition exchanger may also be provided to alter the power absorbing characteristics by altering the fluids composition