Cussons H105 Podded Propeller Dynamometer System is a smaller, lower rated model, dynamometer suitable for self-propulsion tests in moderate sized models as well as open water testing of similar sized model podded propulsions systems.
Following the development and success of the H101 Podded Propeller Dynamometer, primarily designed for open water testing of podded propulsion systems or large self-propulsion models we were encouraged to develop a smaller, lower rated podded propeller dynamometer suitable for self-propulsion tests in moderate sized models as well as open water testing of similar sized model podded propulsions systems.
The new lower rated Podded Propeller Dynamometer is called the H105. The H105 is designed on similar arrangement as the H101 with a water tight non-contact telemetry thrust and torque dynamometer fitted to a precision gearbox that the pod housing can be fitted around.
The H105 has also been designed for use with a suitably rated balance, called the R350 for the measurement of the unit force of the pod as well a light weight suitably rated DC drive motor fitted with a hollow shaft encoder to measure the speed.
The H105 / R350 has been designed for supply with mounting frames to mount the system in single or with a second system for twin screw arrangements with in a ship model. We can also supply a support frame, designed with height adjustment to be mounted from the customers carriage support frame to carry out open water tests of the pod models.
The H105 / R350 offers the following features:
Optional Equipment– Alternatively we can supply the H105 combined with a G102 – three component balance / steering mechanism facilitating measurement of lift, drag/unit thrust, etc. as well as steering torque (only available on request.) – Pod Housing based on typical pod geometry published by Memorial University.
R350 Single Component Balance
Propeller Dynamometer Description:
The drive motor is fitted vertically above the dynamometer. The power is transmitted through a high performance 2:1 transmission ratio gearbox, through bevel gears from the vertical motor shaft to the single horizontal propeller shaft. The high performance gearbox is extremely compact and able to transmit the high power inherent in such a compact design of dynamometer.
The torque and thrust full bridge strain gauge sensor units are directly connected to the shaft couplings at the ends of the gearbox in a pressure tight casing. A high frequency (HF) telemetry system transmits data from the sensor units via antennas mounted to the gearbox; these same antennas are used for inductive power supply to the transducers. The HF signals are converted providing the analogue signals between 10 Volts, thus reducing the number of components and cables, whilst minimising the space requirement with this exceptionally compact Propeller Dynamometer design.
The propellers are mounted directly on the shaft of the sensor units so there are, therefore, no friction losses. The gearbox and sensor units are housed within generic pod geometry, representative of a typical streamlined pod propulsion unit. Customised streamlined geometry for the housing can be supplied at additional cost. Both the generic and customised housings are additional accessories.
When in combination with either a single component balance such as R350 or additional multiple component balance, additional forces acting on the podded Propeller Dynamometer (e.g. drag, lift, etc.) can be measured simultaneously with the propeller thrust and torque.
Because of the requirement for high-strength, many of the H101 Podded Propeller Dynamometer components that would come into contact with Towing Tank water is manufactured from a Brass alloy now as standard, or stainless steel wear required or Type 7075 Aluminium Alloy, a material often used in the aerospace industry.
Integrated R350 Balance Description:
This balance is specially design for use with the H105 Podded Dynamometer when installed in a ship model or from the carriage support frame for open water testing. The balance incorporates a drive shaft with universal joints that is vertically positioned in the centre of the balance to connect the drive through to the podded dynamometer gearbox. The shaft is located in rolling bearings in the top plate and has negligible influence on the load gauge readings. A calibration rig is provided to enable the load cell constant to be determined without removing the load gauge from the balance. The rig uses calibrated masses for loading (masses are not provided with the equipment.)
Single exchangeable load sensor fixed in the X plane arrangement allowing the measurement of forces resistance/thrust.
Forces are transmitted to the sensitive load sensor linearly via special coupling rods design to remove the risk of buckling and beam transducers;
The Unique design of the R350 allows the dynamometer to be driven through a watertight drive shaft fitted with universal joints that is non-compliant with the forces being measured within the balance through its low loading sensitive strain gauged load sensor;
The Floating balance design with coupling rods in the X plane and fixed in the Y & Z places by a parallelogram arrangement with stainless steel flexures.
Static Calibration device designed to calibrate the R350 prior to tests. Masses are not provided.