Ultrasound scans can measure the efficiency of car engines.
Normally used to monitor the progress of pregnancy and the development of babies in the womb, ultrasound scans could now have a role in testing the health of a modern combustion engine.
Rob Dwyer-Joyce, Professor of Lubrication Engineering at the University of Sheffield's Department of Mechanical Engineering in the UK has devised a method of using ultrasound to measure the efficiency of an engine's pistons.
Understanding the way in which lubricating oil works inside the seal between the piston rings and the cylinder is one of the key elements in improving engine fuel efficiency. But, with the cylinders fully enclosed when the engine is running, real-time analysis of piston and lube interaction becomes a real challenge.
The Sheffield team measure the lubricant film by transmitting ultrasonic pulses through the cylinder wall from sensors attached to the outside. The reflections from these pulses are then recorded and measured.
"There is a real urgency, now, to improve energy consumption in cars," says Professor Dwyer-Joyce. "The energy used by the piston rings alone amounts to around four pence (64 cents) in every litre of fuel - there is a lot at stake in getting the lubrication right."