Waveguides for non-invasive measurement of flow in a high temperature pipe and apparatuses, systems, and methods of use thereof

Abstract

A method, apparatus, and system according to which first and second transducers are connected to first and second waveguides, respectively, the first and second waveguides are connected to a pipe, and ultrasonic wave signals are exchanged between the first and second transducers, said ultrasonic wave signals passing through the first and second waveguides, the pipe, and a fluid in the pipe. A temperature of the fluid flowing in the pipe may exceed about 600° C. The first and second waveguides insulate the first and second transducers from the pipe and propagate the ultrasonic wave signals between the pipe and the first and second transducers, respectively, so that the ability of the first and second transducers to exchange the ultrasonic wave signals is not adversely affected by the temperature of the fluid in the pipe. The first and second waveguides may be made of a calcium silicate technical ceramic.

1 - 20 . (canceled) 
     
     
         21 . An apparatus comprising
 first and second waveguides, each formed in the shape of a prism, and adapted to be connected to a pipe; and   first and second transducers adapted to be connected to the first and second waveguides, respectively, and to exchange ultrasonic wave signals through the first and second waveguides, the pipe, and a fluid flowing in the pipe;   wherein the first and second waveguides are configured to permit propagation of the ultrasonic wave signals between the pipe and the first and second transducers, respectively, while maintaining an acoustic attenuation through the first and second waveguides at an acceptable level that is small enough to permit ultrasonic wave signals from one of the transducers to pass through the waveguides and be detected by the other of the transducers, so that the ability of the first and second transducers to exchange the ultrasonic wave signals is not adversely affected by the temperature of the fluid flowing in the pipe.   
     
     
         22 . The apparatus of  claim 21 , wherein the first and second waveguides are each tapered so that contact areas between each of the first and second waveguides and the pipe are smaller than contact areas between the first and second waveguides and the first and second transducers, respectively. 
     
     
         23 . The apparatus of  claim 21 , wherein the first and second waveguides are each machined to include a surface configured to matingly engage an external surface of the pipe. 
     
     
         24 . The apparatus of  claim 23 , wherein a machined surface of at least one of the first or second waveguides define a curved surface configured to match a corresponding cured surface of the pipe. 
     
     
         25 . The apparatus of  claim 23 , wherein a machined surface of at least one of the first or second wave guides defines a flat surface configured to match a corresponding flat surface machined into the external surface of the pipe. 
     
     
         26 . The apparatus of  claim 25 , wherein the engagement between the machined surface and the corresponding flat surface is configured to increase a transmission of the ultrasonic wave signal into the pipe by a factor of 10. 
     
     
         27 . The apparatus of  claim 26 , wherein the mating engagement of each of the first and second waveguides is configured to permit propagation of the ultrasonic wave signals through the first and second waveguides at an angle greater than or equal to about 40 degrees and less than or equal to about 70 degrees with respect to a longitudinal axis of the pipe. 
     
     
         28 . The apparatus of  claim 21 , wherein the first and second waveguides may exhibit the acceptable level of acoustic attenuation by comprising a material having a sound velocity in a range of 2200 to 3500 meters per second. 
     
     
         29 . The apparatus of  claim 21 , wherein the first and second waveguide have a shape configured to insulate the first and second transducers from the pipe. 
     
     
         30 . A system comprising
 a pipe having a fluid in excess of 600° C. flowing therethrough;   an apparatus including
 first and second waveguides matingly engaged with an external surface of the pipe, and 
 first and second transducers connected to the first and second waveguides, respectively, and configured to exchange ultrasonic wave signals through the first and second waveguides, 
 wherein the first and second waveguides are configured to permit propagation of the ultrasonic wave signals between the pipe and the first and second transducers, respectively, while maintaining an acoustic attenuation through the first and second waveguides at an acceptable level that is small enough to permit ultrasonic wave signals from one of the transducers to pass through the waveguides and be detected by the other of the transducers, so that the ability of the first and second transducers to exchange the ultrasonic wave signals is not adversely affected by the temperature of the fluid flowing in the pipe; and 
   a control unit communicatively coupled with each of the first and second ultrasonic transducers and configured to control the exchange ultrasonic wave signals therefrom.   
     
     
         31 . The system of  claim 30 , wherein the first and second ultrasonic transducers are arranged on a common side of the pipe and exchange ultrasonic signals via reflection on an opposing internal surface of the pipe. 
     
     
         32 . The system of  claim 31 , wherein the mating engagement of each of the first and second waveguides is configured to permit propagation of the ultrasonic wave signals through the first and second waveguides at an angle greater than or equal to about 40 degrees and less than or equal to about 70 degrees with respect to a longitudinal axis of the pipe. 
     
     
         33 . The system of  claim 30 , wherein the first and second ultrasonic transducers are arranged on opposing sides of the pipe and exchange ultrasonic signals therethrough. 
     
     
         34 . The system of  claim 30 , wherein the first and second waveguides are each formed in the shape of a prism. 
     
     
         35 . The system of  claim 34 , wherein the first and second waveguides are each tapered so that contact areas between each of the first and second waveguides and the pipe are smaller than contact areas between the first and second waveguides and the first and second transducers, respectively. 
     
     
         36 . The system of  claim 35 , wherein an end of each of the first and second waveguides is machined to match a contour of the external surface of the pipe. 
     
     
         37 . The system of  claim 30 , wherein the control unit is configured to
 send a control signal to the first transducer that causes the first transducer to emit an ultrasonic signal,   receive a response from the first transducer on receipt of the ultrasonic signal at the first transducer after propagating through the fluid, and   calculate a transit time of the ultrasonic signal to determine the flow velocity of the fluid flowing in the pipe.   
     
     
         38 . The system of  claim 37 , wherein the control signal is a single wave high voltage pulse. 
     
     
         39 . The system of  claim 30 , wherein the control unit is wirelessly coupled with each of the first and second transducers. 
     
     
         40 . A method comprising
 providing the apparatus of  claim 21 ;   connecting the first and second transducers to the first and second waveguides, respectfully;   engaging a surface of each of the first and second waveguides with a complementary surface of the pipe;   exchanging ultrasonic wave signals between the first and second waveguides, the pipe, and a fluid flowing in the pipe, the fluid having a temperature in excess of 600° C.;   insulating, using the first and second waveguides, the first and second transducers from the pipe; and   maintaining, using the first and second waveguides, an acoustic attenuation of the ultrasonic wave signals.