摘要
以精度较高的现场测量Hamilton的原位测量所得数据为标准,对比研究了钱正明的直立同轴衰减测量法、刘强的垂直轴差距衰减测量法和我们课题组的同轴差距衰减测量法等3种研究海底沉积物声衰减的实验室测量方法。通过3种实验测量方法所得数据跟Hamilton原位测量所得数据进行对比,分析了以上实验室方法的优缺点,并分析了声衰减与样品长度和测量频率的关系。同轴差距衰减测量法与直立同轴衰减测量法相比,前者在消除测量仪器和耦合衰减误差方面,以及在实验样品长度方面更合理。同轴差距衰减测量法与垂直轴差距测量法相比,同轴差距衰减测量法在原理上保证了声波传播能量接收的同轴性和同指向性,其实验数据比利用相同实验仪器的垂直轴差距测量法的数据更准确。
Taking the precise measurement data by Hamilton＇s parallel differential distance attenuation measurement method （PDDAMM） as the standard, the authors compare the Qian＇s vertical coaxial attenuation measurement method （VCAMM） and Liu＇s vertical differential distance attenuation measurement method （VDDAMM） with their coaxial differential distance attenuation measurement method （CDDAMM）. By comparing the data from these three experiments with those by Hamilton＇s method, the authors further analyze the connection of attenuation with sample length and measurement frequency as well as the benefits and drawbacks of these three experiments. Compared with VCAMM, CDDAMM is much more advisable in respect of reducing perturbations, which result from measuring instrument and the coupling between sample and transducer, and of sample length. Compared with VDDAMM, CDDAMM ensures in theory the coaxiality and directivity of compression wave in spreading process, and its data are much more precise than those by VDDAMM when using the same laboratory instrument.
出处
《热带海洋学报》
CAS
CSCD
北大核心
2009年第3期40-44,共5页
Journal of Tropical Oceanography
基金
国家自然科学基金项目(40876018)
中国科学院边缘海地质重点实验室资助项目(MSGL08-17)
关键词
海底沉积物
声衰减
实验室测量
seafloor sediment
acoustic attenuation
laboratory measurement
