【作者】 高翔；

【导师】 张锦荣； 张培信；

【作者基本信息】 中国原子能科学研究院 ， 核技术应用， 2003， 硕士

【摘要】 本文内容包括流量测量现况，同位素示踪技术在管道流量测量方面的方法和应用，伽玛射线截面相关技术的原理、方法和应用；通过固液两相流现场实验，建立一套基于同位素示踪和密封源技术的相关流量测量方法，详细研究水力输运中固体成分的滑移速度规律；本文首次提出利用频谱分析和截面相关联用技术来处理数据，并取得较高的测量精度。 流量计是工业用仪表的主要部分，而固液、固气、液气等多相流的测量是难点。虽然已开发了不少多相流流量计，但通用于各种具体的对象则很困难，精度也不高，难以满足工业生产的需要。利用互相关法结合传统的非接触测量方法，可以提高测量精度和数据处理速度。在英国、德国等发达国家，从1990年开始，每年都投入大量资金用于截面相关法应用研究，这当然和近十年来的计算机技术快速发展密切相关，作为虚拟仪器的一种数据处理方法，截面相关法在波形分析、延迟时间测量、图像探测等方面都非常有用。我国这方面的理论研究和实际应用较少，所以利用截面相关法测量管道流体流量是一种新的技术，尤其是结合同位素示踪技术，截面相关技术将传统的测量方法完善和提高。 作为本文重点建立了一套利用同位素示踪和密封源技术来测量流量的方法。利用密封源透射法测量管道流体的瞬时密度截面，由于多相流中存在湍流和固体等大密度体的影响，造成密度截面随时间波动，而波动的密度截面在一定距离内保持相对稳定，这就为截面相关分析提供了可能。利用两个或多个射线探测器同时记录沿线各点的密度信息，储存在计算机内，进行频谱分析和截面相关运算，即可得出准确的渡越时间(通过时间)，进而计算出管道流体流量。通过现场实验，建立了一套基于同位素示踪和密封源技术的流量测量方法和测量装置，包括示踪剂的选取和用量估算，标记同位素的实验方法，并建立了一种计算机数据处理方法和程序，摸索出一套优化测量方法和数据处理技巧。 通过水力输运实验，对水力输运垂直管道中的不同大小的固相物体(石块)的滑移速度进行了准确的测定，研究了滑移速度同管道水的流速的关系，从而为水力采矿输运提供了一种新的研究方法和有用数据，为节约能源和减少损耗，提高运输效率起到重要作用。中国原子能科学研究院硕十学位论文 本文提出一种新的流量测量数据处理方法—利用频谱分析和截面相关联用技术。这是一种复合的计算机数据处理技术，优点在于结合了谱分析法的频域滤波的优点和截面相关算法快速准确的优点，具有抗干扰性强、计算准确快速的特点。通过几种方法的实验对比和验证，说明截面相关技术是比较先进的流量测量数据处理方法，而利用频谱分析的截面相关方法是在恶劣情况下精度最高的数据处理方法，管道流速测量精确度优于0.5%。最后的结论是:利用密封源技术和同位素示踪技术，和先进的截面相关数据处理方法，可以精确测定管道流量和两相流中固、液等各单相的流速，而且取得很高的测量精度。 根据调研，本论文研究工作在国内属于首次。更多还原

【Abstract】 This paper presents the current methods of various flow rate measurements, isotope tracer techniques and applications in flow rate measurement, the basic principle of cross-correlation, the methods and applications of cross-correlation; In situ solid-liquid flow experiments, the paper set up a series of cross-correlation techniques in flow rate measurement using isotope tracer and sealed source, and investigates the rules of solid slip velocity in the hydro-transport. The paper gives out a new method to process data for flow rate measurement using the combination of frequency spectral analyses and cross-correlation technique, and obtained improved accuracy.Flow meters are very important for industrial processes. In fact, it’s very difficult to measure the multiphase flow such as solid-liquid and solid-gas or liquid-gas flows, although there have been many kinds of multiphase flow meters. More and more studies indicate the improvement in accuracy by using the cross-correlation technique combined with traditional meters. Especially gamma ray cross-correlation meters using sealed sources, are the best choice of multi-phase flow meters. The cross-correlation technique contains powerful data process tool for waveform analysis, delay time determination, thanks to the rapid development of computer. Many companies in the world began to study the techniques of cross-correlation flow meter from 1990.This paper mainly presents a method to measure flow rate by using isotope tracers and sealed sources. Gamma ray absorption method can be used to measure the instantaneous density section of the flow in pipeline. For multiphase flow, the signals from the two-neighboring detectors are the functions of time interval between the two signals, which can be calculated by cross-correlation method. The multiphase flow should be analyzed by a combination of radiotracer and y transmission measurements. Such approach gives an opportunity to take the advantages from both methods, and to set up a series ofmethods and devices for flow rate measurement in detail.In the presented hydro-transport experiment, the value of slip velocity from differences of specific gravity of components and solid fraction’s concentration in mixture can be accurately obtained, due to application of sealed radioactive sources and tracers. This result gives out a new method and valuable data for hydro-transport, and makes very important effect to save energy and reduce losses and to increase the transport efficiency.This paper gives out a new data processing method for flow meter. It is a combination of frequency spectral analysis and cross-correlation techniques. It’s has the advantages of anti-jamming and fast accurately calculating. The experiment proves the error of transportation delay was keep below 0.5%, it’s the one of the best method in the world. Last conclusion is gamma ray cross-correlation technique can be used to determine the velocities of the solid and liquid phases, and obtain improved accuracy.The work described in this paper is the first of its kind in China by information searches.更多还原