標準號：IEC/TS 61949-2007
中文標準名稱：超聲學.原位表征.有限振幅超聲波束原位曝光估計
英文標準名稱：Ultrasonics - Field characterization - In-situ exposure estimation in finite-amplitude ultrasonic beams
標準類型：A42
發布日期：1999/12/31 12:00:00
實施日期：1999/12/31 12:00:00
中國標準分類號：A42
國際標準分類號：11.040.55;17.140.50
適用范圍：This Technical Specification establishes:? the general concept of the limits of applicability of acoustic measurements in waterresulting from finite-amplitude acoustic effects;? a method to ensure that measurements are made under quasi-linear conditions in order tominimise finite-amplitude effects, which may be applied under the following conditions:? to acoustic fields in the frequency range 0,5 MHz to 15 MHz;? to acoustic fields generated by plane sources and focusing sources of amplitude gainup to 12;? at all depths for which the maximum acoustic pressure in the plane perpendicular tothe acoustic axis lies on the axis;? to both circular and rectangular source geometries;? to both continuous-wave and pulsed fields;? the definition of an acoustic quantity appropriate for establishing quasi-linear conditions;? a threshold value for the acoustic quantity as an upper limit for quasi-linear conditions;? a method for the estimation of attenuated acoustic quantities under conditions of nonlinearpropagation in water.