Knowledge of an air moverís aerodynamic efficiency
and the efficiency of its mechanical drive (motor and bearings) is
essential to making further progress in new air-mover designs.
The Micro Dynamometer (μDyno)
is designed to measure the power absorption of small fans, blowers and
pumps and the power delivery of small motors. It does this by measuring
the dynamometerís stator reaction torque and rotor shaft speed.
The μDyno is compatible
with the Model 798 Precision Air Flow Measurement System for simultaneous
dynamometer and airflow measurements.
The μDyno is similar in
concept to cradle dynamometers used throughout industry for over 75 years.
In these designs, a motor/generator is cradled in low friction bearings
and the reaction torque to keep the cradle in static equilibrium is
measured. Knowing the reaction torque along with rotational speed allows
the calculation of shaft power delivered or absorbed by the dynamometer.
The μDyno uses a frictionless, stiction-free flexure pivot to support the armature. This allows for more miniscule torque measurements that could not be made with a typical bearing.
The μDyno is capable of
measuring torques of 0.1 to 50 mNm at speeds up to 20,000 RPM. We can
measure shaft power ranging from 0.01 to 50 watts with a resolution of
about .01 to 5 mW depending on speed. The μDyno
is capable of motoring or absorbing operation, making it suitable for
testing air moving device elements such as impellers as well as the motors
that power the air moving devices.
Currently, the μDyno is
only made to order. Please inquire about pricing and lead-times on a model
suitable for your applications. Contact us for more details.
Entirely frictionless through use of flexure pivot
Four-quadrant operation allows motor or absorbing operation with clockwise or counterclockwise rotation
Works with both axial and radial flow fans
Compatible with the Hill Engineering model 798 Air
Flow Measuring System
Speed range designed for small fans and motors with a range up to 20,000 RPM
Power measurement range from 0.01 to 50 W
Can accept holding fixtures for a wide variety of
fans, blowers, pumps and motors
Accurate to 0.01-0.1% for speed measurement, 0.5-2% for
torque measurement which leads to ~2% accuracy for power measurements
Provides digital readout of speed, torque and power