Apparatus for measuring height of foreign substance in pipe

A measuring device for measuring the height of a foreign object in a pipe comprising:

• an ultrasound transmission unit including an ultrasound generator disposed in a first area of an outer surface of a pipe through which fluid passes, and generating ultrasound, and a transmission medium disposed between the ultrasound generator and the first area to transmit the ultrasound to the first area;
• an ultrasound receiving unit including a receiving medium unit disposed in the second area of the outer surface of the pipe, and consisting of an ultrasound receiver, and a receiving medium disposed between the ultrasound receiver and the second area, and wherein the receiving medium unit transfers the ultrasound transmitted from the first area to the second area through the inside of the pipe to the ultrasound receiver, and the ultrasound receiver receives the ultrasound transmitted through the receiving medium unit;
• and
• a signal measurer connected to the ultrasound receiver for measuring the ultrasound signal received by the ultrasound receiver or a signal corresponding thereto,
• wherein the ultrasound generator is configured to generate longitudinal wave type ultrasound, and the transmission medium includes a first ultrasound type conversion unit for converting the ultrasound of a longitudinal wave type into ultrasound of a shear wave type,
• wherein the receiving medium unit includes a second ultrasound type conversion unit for converting shear type ultrasound into longitudinal type ultrasound,
• wherein the height of the foreign object in the pipe is determined based on a transmission angle (θ2) in a fluid within the pipe, a thickness (t) of the pipe, and an outer diameter (D) of the pipe,
• wherein the transmission angle (θ2) in the fluid within the pipe is determined by at least one of a shear wave velocity (CS1) in the pipe, a longitudinal wave velocity (CL2) in the fluid, and an incidence angle (θ12) from the pipe to the fluid.