Test results on an electromagnetic current sensor with an "open" design

An electromagnetic current sensor with a unique "open" design was developed by J. R. Olson of the Naval Undersea Center. It was tested for steady flow accuracy and cosine response in the horizontal and vertical planes. The sensor's configuration was designed to minimize hydrodynamic disturbances of the current flow and to offer good linearity and directivity response. Test data revealed the sensor's steady-flow measurement uncertainty to be ±2.5 percent of full scale. Horizontal directivity errors were less than ±4 cm/s and 5 cm/s for half- and one-knot test flows. The major contributor of error for the cosine response was determined to be an imbalance in amplifier gain between the sensor's two measuring axes. Vertical directivity results were too noisy for reliable analysis, and the problem was believed to be caused by a distortion of the sensor's magnetic field during testing. 1976 NOS (National Ocean Service) Library Public Domain 1935

美国海军水下作战中心（Naval Undersea Center）的J·R·奥尔森（J. R. Olson）研发了一款采用独特“开放式”设计的电磁式海流传感器（electromagnetic current sensor）。该传感器针对水平与垂直平面内的稳流精度及余弦响应特性进行了测试。该传感器的结构设计旨在最大限度降低海流所受的流体动力扰动，同时具备优异的线性度与指向性响应性能。测试数据显示，其稳流测量不确定度为满量程的±2.5%。针对半节（knot）与1节（knot）流速的测试海流工况，水平指向性误差分别小于±4 cm/s与5 cm/s。经分析，余弦响应的主要误差来源为传感器两个测量轴之间的放大器增益失衡。垂直指向性的测试结果噪声过大，无法开展可靠分析，该问题被认为源于测试过程中传感器磁场发生畸变。1976年，国家海洋服务局（National Ocean Service, NOS）图书馆馆藏，公有领域，文献编号1935。