Watertight Propeller Dynamometer

Product Description

Watertight Propeller DynamometerThe Watertight Propeller Dynamometer of high capacity is sealed against pressure of up to 1 bar above atmospheric pressure and against relatively high vacuum (1 bar = 10 to the power 5 N/m2 = 0.1 MPa).It is thus suitable for use in the measuring section of cavitation tunnels, as an inner drive dynamometer in ship models or in dummy bodies mounted in the measuring section of a cavitation tunnel. The dynamometer can be used also for propulsion tests with relatively high torque and thrust values in ship models under water. That has slightly larger dimensions, but is of similar appearance.Idle friction of the measuring shaft is small despite the use of sealing rings and is approximately 0.3 Nm for dynamometer and 0.4 Nm for dynamometer Specification of Watertight Propeller Dynamometer Rated torque 80 NmRated thrust 2.2 kNOverload in torque and thrust permitted for a short moment 30%Maximum constant speed in water 4500 rpmMeasuring system for torque and thrust measurement full bridge strain gauge typeInput resistance of the full bridge for thrust and torque measurement (supply diagonal) about 256 Output resistance of the full bridge about 240 Recommended supply voltage for thrust and torque measurement (do not use constant current) d.c. or a.c. up to 8 VMaximum supply voltage for thrust and torque measurement 20 VSensitivity at rated load for thrust and torque measurement about 1.5 mV/VCorresponding to an apparent strain at rated load of about 3000 /mPulse generator for speed measurement 60 pulses/1rev.Air pressure for brush lifting, above atmospheric pressure 1.2 0.2 barWeight without cables, about 11.3 kgMaterial of the casing stainless steel(Cr-Ni-type) and PlexiglasMaterial of the shaft ends stainless steel(Cr-type)1 bar = 10 to the power 5 N/m2 = 0.1 MPs