Ultrasound the key to more efficient engines?
Engineers at the University of Sheffield have, for the first time, devised a method for using ultrasound to measure how efficiently an engine's pistons are moving up and down inside their cylinders.
"There is a real urgency now to improve energy consumption in cars," noted Professor Rob Dwyer-Joyce, form the university's Department of Mechanical Engineering. "Our method will allow engine manufacturers to adjust lubrication levels with confidence and ensure they are using the optimum level for any particular engine, rather than over lubricating to ensure engine safety.
"The energy used by the piston rings alone amounts to around 4p in every litre of fuel – there is a lot at stake in getting the lubrication right."
While conventional methods for seeing what's going on inside the car's cylinders rely on expensive computer models or invasive methods, the Sheffield team set about measuring the lubricant film by transmitting ultrasonic pulses through the cylinder wall from sensors attached to the outside.
The reflections from these pulses can then be recorded and measured.
The team says it is ready to commercialise the technology and is now looking for industrial partners who might be interested in pursuing the approach.
"Our system could provide major efficiency savings in car engines, but it could also be used on the larger diesel engines in deep water marine vessels, some of which use up to 1tonne of oil each day," Professor Dwyer-Joyce concluded.
