光纤液位仪应用于顶罐的研究

近年来，基于光弹效应的光纤液位传感器发展迅速。其传感器内采用光桥补偿光路，可以克服多种外界因素对测量产生的不利影响．但由于它的绝对压强测量原理，致使它在浮顶油罐上的应用一直是人们所关注的问题．本文从理论和实验两方面证明，在浮顶罐的液位测量中，运用ＩＭ８５－Ｉ型光纤液位仪，可以获得与开顶罐相同的测量精度．而与浮顶的重量及浮顶与罐壁的摩擦力无关．     

光纤液位传感器

光纤液位传感器ＡｎｂｏＷａｎｇ等１．前言液位测量在工业中获得了广泛的需求，尤其在石油和化学处理工业中。有时，有必要采用无电流传感触头这种安全方法来测量易燃液体的液位。液位测量可分为连续液位测量、离散液位测量和点液位测量。在近十五年期间，已经研制成功了...     

高精度连续型光纤F-P腔液位传感器

提出一种基于光纤法布里-珀罗(Fabry-Perot,F-P)腔干涉仪原理的高精度连续型光纤液位传感器,它根据不同的液体高度产生不同的压强的原理实现液位测量。传感器通过MEMS技术和微光结构加工工艺研制,确保了传感器各项设计要求;系统采用双通道补偿光路以及双路输出比值为信号的处理方式,有效降低了环境因素的影响;利用低双折射单模光纤结合消偏技术,大幅减少了光路中“寄生干涉”和“偏振诱导信号衰落”对光纤F-P传感器测量精度的影响。实验表明,该传感器的灵敏度为0.8mV/mm,测量精度为<±2mm,分辨力为<±1mm,系列样品中最大量程可达30m,而且结构简单,安装方便。     

采用光纤传感器的电子塞规的设计

针对内孔零件批量快捷测量的问题，提出了基于反射式光强调制型光纤位移传感器的电子塞规测试系统。介绍了系统的测量原理与机械结构，设计了光纤位移传感器的结构和补偿算法。     

飞机雷达燃油液位测量系统实现

介绍了飞机雷达燃油液位测量系统的构成及在飞机供油系统油量数据采集和处理中的应用实例,论述了雷达燃油液位测量技术的发展趋势.     

基于OV6630和单片机光纤液位传感电路的研究

提出了一种基于图像采集芯片OV6630和高速单片机8051f120的数字式绝对码光纤液位传感电路的设计方法.利用OV6630采集经液位调制的光纤亮暗图像信息,所得图像数据经过8051f120的处理,最终得到准确的液位信息,送入显示模块.传感电路具有准确的数据获取能力和高速的数据处理能力,可应用于液位的动态检测与监控,在汽油、航空煤油等防爆和精度要求高的液位测量领域具有较大的研究价值和意义.     

多点感温式液位传感器的研究

液位测量的方法很多,针对传统液位传感器难以实现准确可靠的液位测量,提出了一种多点感温式液位传感器。它是基于发热体在气(汽)体和液体中放热系数差异显著的特点,设计的一种变液位测量为温差测量的传感器。实验表明,研制的多点感温式液位传感器原理正确,结构可行,性能可靠,可承受高温、高压,能够准确地判断出液气(汽)界面,有必要推广到压力容器内应用。     

低精度液位测量电路设计

针对低精度的液位测量,利用开关霍尔元件并结合单片机技术设计了一种低精度的液位测量传感器,对传感器的测量原理、测量电路、信号处理电路进行了介绍。     

强度调制型光纤传感器用电路研究

在强度调制型光纤传感器中,光源发光强度和光电接收器工作的稳定性,是决定测量精度的关键因素。设计了具有软启动功能和恒亮度控制的光源驱动电路,所用光电接收器能满足测量系统要求。实验表明,该电路软启动效果明显,能抑制电压波动冲击,输出电压稳定度优于0.8%,为提高该类传感器测量精度提供了有效的手段。     

光闸式光纤位移传感器

本文介绍了一种强度调制型光纤传感器-光闸式光纤位移传感器,推导出其调制函数关系式.通过实验表明,与传统的位移传感器相比,其具有精度高、重复性好、无滞后性等优点.引进了均匀光斑装置后能提高工作区域范围,该善线性度.增加了参考通道后有效地减小了光源波动及光纤抖动等干扰信号的影响,更加有利于其在工程中的实际应用.     

Binary spatial amplitude modulation of continuous transverse modal electric field using a single lens for mode selectivity in multimode fiber

The demand for portable real-time optical applications such as medical optical sensors and optical transceivers instigate the need for compact optical designs. The aim of this paper is to demonstrate a new, compact design for binary spatial amplitude modulation in a mode-selective transmitter in a multimode fiber, adapted from microscopy. Results show that it is possible to retrieve the original continuous-amplitude transverse modal electric field from the binary amplitude-modulated image using a single lens. The retrieved image is in good agreement with the original image.     

光纤出射光强分布研究

对多模光纤出射光束的光强分布用横向位移法进行了理论分析和实验研究,并用数值计算的方法分析实验测量数据.结果表明,高斯光束可以很好地描述光纤出射光强的分布,光纤出射光束光强分布参数主要与光纤芯径和出纤光功率等有关,为强度调制型光纤传感器的优化研制提供了必要的实验依据.     

Mathematical Modeling of Intensity-Modulated Bent-Tip Optical Fiber Displacement Sensors

Intensity-modulated optical fiber displacement sensors have a potential to be used in a number of applications, including those in industry, military, aerospace, and medicine. Compared with other types of optical fiber sensors, intensity-modulated sensors offer distinctive advantages in that they are usually less complex, inexpensive, and less sensitive to thermal-induced strain. They are able to perform accurate contactless sensing while being of a small size and having a wide dynamic range. A common form of the intensity-modulated optical fiber sensor performs its measurement by making use of a pair of straight parallel optical fibers integrated with a moving reflector modulating the reflected optical signal intensity. Although such an optical modulation configuration exhibits good sensing ability, improvement on its performance could still be made to widen the extent of its application areas. This leads to the development of more effective intensity modulation mechanisms utilizing bent-tip optical fibers and a reflector that can either laterally slide or longitudinally move with reference to the central axis of the fibers. This paper describes such alternative sensing structures and demonstrates the derivations of mathematical models proposed for analyzing their sensing characteristics. Based on experimental studies, the models are verified and validated for the analysis of sensitivity and linearity.      

Low-cost optical amplitude modulator based on a tapered single-mode optical fiber

A new, to our knowledge, modulator based on a tapered single-mode optical fiber is introduced. The electro-optic device consists of a tapered optical fiber placed on a resonator made of a piezoelectric material. An electrical signal applied to the piezoelectric material makes the taper bend, and that displacement produces a modulation in the intensity of the optical signal traveling through the fiber. This device is very easy to build and is low in cost. Because of its nature, this new device might be very useful in optical fiber sensors. Its performance is analyzed, and the results are discussed.     

航空发动机数据检测与控制信号的光纤传输

本文阐述一个可用于航空发动机数据检测和控制的光纤传输系统。其中包括信号的调制电路、电光变换、光检测器、均衡放大器和滤波器等。分析了光纤传输系统与计算机、传感器和执行机构之间的连接方法以及主要环节的电路结构。最后给出模拟实验和在航空发动机上的试车结果。     

Power budget considerations for optically activated conventionalsensors and actuators

Optically powered conventional instrumentation with optical fiber links that combine the advantages of a familiar technology and of fiber optics is described. A number of examples are given of the development of pneumatic pressure sensors and actuators with reduced power consumption that are operated by optical power and incorporated with fiber-optic links. Their performance and power budget are discussed. They are particularly applicable to transmissions through regions having high EM interference, high EM pulses, and explosive, radiative, or corrosive hazards, such as in nuclear power plants, process plants, aircraft, or spacecraft. These low-optical-power transmission and operation characteristics will help to meet safety requirements and to reduce the system cost     

Mach-Zehnder光纤干涉仪相位载波调制及解调方案的研究

本文根据Mach Zehnder光纤干涉仪相位调制与双光束干涉测量的特点 ,提出了一种采用相位调制器 (PZT)实现相位载波调制 ,利用贝塞耳函数进行傅里叶分解实现相位调制信号解调的检测方案。理论分析表明 ,该方案能有效地抑制随机干扰信号对测量精度的影响     

光纤涡街式流量密度计理论研究

本文主要分析了流体的涡漩运动特性,结合强度调制光纤的传感原理,和光纤的微弯损耗特性和多模光纤模式间干涉的结果,设计了一种同时测量流体的流量和密度的新型流量、密度计。该仪器通过光纤频率检测系统和光纤举力检测系统分别检测流体流过漩涡发生体产生的稳定漩涡发生频率f和流体作用在漩涡发生体上的升力。结合“卡门涡街”理论和茹科斯基升力定理计算出流体流量和稳定漩涡发生频率f的线性关系和流体密度与稳定漩涡发生频率f和流体作用在漩涡发生体上的升力的关系。并设计出同时检测漩涡频率f和升举力仪器的系统原理图。     

Determination of the level of a substance in a production vessel at high temperature

A radiofrequency method is considered for determining the level of a substance in a vessel at about 1000°C or more that is used in particular for indicating the level of timber plant production waste (wooden fuel) in furnaces of heat generating units. Construction features of these radiofrequency sensors based on sections of long lines are described in detail. __________ Translated from Izmeritel'naya Tekhnika, No. 8. pp. 29–30, August, 2008.     

Acousto-Ultrasonic Optical Fiber Sensors: Overview and State-of-the-Art

This paper gives a review of acoustic and ultrasonic optical fiber sensors (OFSs). The review covers optical fiber sensing methods for detecting dynamic strain signals, including general sound and acoustic signals, high-frequency signals, i.e., ultrasonic/ultrasound, and other signals such as acoustic emissions, and impact induced dynamic strain. Several optical fiber sensing methods are included, in an attempted to summarize the majority of optical fiber sensing methods used to date. The OFS include single fiber sensors and optical fiber devices, fiber-optic interferometers, and fiber Bragg gratings (FBGs). The single fiber and fiber device sensors include optical fiber couplers, microbend sensors, refraction-based sensors, and other extrinsic intensity sensors. The optical fiber interferometers include Michelson, Mach-Zehnder, Fabry-Perot, Sagnac interferometers, as well as polarization and model interference. The specific applications addressed in this review include optical fiber hydrophones, biomedical sensors, and sensors for nondestructive evaluation and structural health monitoring. Future directions are outlined and proposed for acousto-ultrasonic OFS.