Patent ID: 7424376

Claim:
A sensor ( 100 ), characterized in that the sensor comprises: a conduit ( 106 ) configured for conveying a material (F), the conduit presenting an axial length, the conduit having a noncircular cross-section of major axis (a) and minor axis (b) of respective dimensions (a) and (b) each taken as perpendiculars with respect to the axial length, wherein the cross-section tends to become slightly more circular as pressure internal to the conduit is increased; a vibrator ( 118 , 126 ) configured for vibrating the conduit along a first cross-sectional axis and for vibrating the conduit along a second cross-sectional axis; a sensor ( 114 , 122 ) configured for detecting a first frequency along the first cross-sectional axis (a) and for detecting a second frequency along the second cross-sectional axis (b); and a processor ( 400 ) configured for determining a pressure of the material based on a ratio of the first frequency and the second frequency; wherein the ratio is related to the pressure through first and second inertial moments according to an equation having a form of ( firstfrequency ) 2 ( secondfrequency ) 2 = I a I b , where ( Eq . ⁢ 2 ) I a is the first inertial moment and I b is the second inertial moment.