EMAT detection method of spray cooling characteristics for industrial nozzle

The paper describes a new ultrasonic measurement technology that evaluates a spray nozzle cooling characteristics based on measured time-of-flight data using an electromagnetic ultrasonic transducer (EMAT). A spiral electromagnetism ultrasonic transducer was used to measure the ultrasonic velocity dependence of temperature in a certain thickness metal plate. The instantaneous time-of-flight time data were used to determine the velocity and deduce the interior and surface temperature. To verify the validity of the ultrasonic measurement result, one-dimensional unsteady heat transmission equation is established to compute the heat transfer coefficients (HTC) theoretically compared with ultrasonic measurement results. Through some one-dimensional analysis, this work will show that the HTC is a natural and stable quantity to estimate ultrasonic time of flight measurements.