Today's computer techniques are very good and improving all the time. However, there are still engine parameters, especially component stiffness and damping effects that are hard to predict exactly in a computer model. In the area of the crank damper's final effects on the engine, there is still no substitute for finishing a development program with an actual measurement of the torsion levels remaining in the crank. This testing has significant value as it allows some "fine tuning" of the damper by including:
- Actual inclusion of all the rotating group parameters that might have had small inaccuracies in the engine model
- Real-time temperature conditions of the damper
- Driveline effects added to the crank
BHJ has the equipment and expertise to do this final validation measurement of the engine either on an engine dyno or in the car on a chassis dyno. The set of equipment as a whole is called a torsiograph. The various pieces are:
- Vibration Sensor or Pickup. This is a rotating tone wheel mounted to the nose of the crank at the damper hub. The tone wheel is read with a magnetic sensor and sends a frequency-modulated signal
- Torsional Converter. This is an electrical device that separates the carrier frequency from the frequency modulation portion and sends the result onward
- Vibration Analyzer. This is a device that separates the FM portion of the signal into Torsional Amplitude at the discrete vibration orders and displays them along with RPM in a 3D display called a "waterfall". When the data is taken during a power pull on the dyno, the waterfall display gives a full "map" of the torsion across the RPM range of the engine. The analyzer also allows selection of any single order to be plotted vs. RPM in a 2D plot for easier scaling and presentation
- Printer / plotter. This allows paper documentation of the data in waterfall or 2D format
Independent Dyno Test Validation Service
The natural progression in any successful engine program is the verification and validation of the design effort. BHJ Dynamics offers our Dyno Test Validation program as an independent service. You can have your engine design tested using the equipment listed above without having BHJ design your damper. What is important for engine builders, is measuring the torsional levels that remain, in order to fine-tune the design for optimum performance.
Accessories, such as isolation pulleys, drive mandrels, ignition trigger wheels and other components are commonly required as part of damper projects.
Design and manufacturing services are also available for components such as these, either as part of a damper project, or separately.
Contact us to enquire about BHJ component development programs.