Acoustic radiation force on fused silica spheres, and intensity determination

The advantages of using fused silica spheres as the target in the radiation force method of acoustic intensity determination are considered. Experimental determination of the radiation force function, for fused silica spheres in water in the range of ka 2–24, was carried out. The experimentally obtained values of the radiation force function agree within 2% of those calculated from the theory of the radiation force on solid elastic spheres. This makes possible determination of ultrasonic intensity and calibration of acoustic probes with uncertainties <2% to values of ka=24, where the accuracy of the radiation force method with stainless steel spheres becomes reduced. The experimental conditions necessary for the realization of this accuracy are discussed. Subject Classification; 25.45; 30.80; 35.80; 85.22.