【作者】 李霞；

【导师】 秦建敏；

【作者基本信息】 太原理工大学 ， 检测技术与自动化装置， 2008， 硕士

【摘要】 本论文是在国家自然科学基金项目“冰层厚度传感器及其检测方法的研究”(60672028)资助下进行的一项应用基础研究。利用空气、冰与水的电阻率差异的原理进行冰层厚度测量的传感器参加了第21、22次南极科学考察海冰观测项目。通过分析大量的海冰观测数据,我们发现利用电阻率差异测量冰层厚度对海冰和空气的上界面的判断比较精确,但是对于海冰和海水混合物的下界面判断不明显,误差较大。所以,在此基础上提出了利用空气、冰与水的电阻、温度特性差异进行冰情检测的新方法,减小对下界面的判断误差。同时,当气温与冰温相差较大时,可以用温度差异来判断上界面,提高上界面的测量精度,实现多参数的融合检测。以便帮助我们分析冰层厚度、冰下水位、冰层内部的性状,从而帮助我们预测冰层变化趋势,进行冰情测报。因而本项目的研究具有重要的科研和实际应用价值。本文在作了大量的初期机理实验后,通过对室内和室外的实验数据分析找到空气、冰与水的电阻、温度特性差异,为传感器的制作提供了理论基础。通过分析比较市场上各种温度传感器的特性,选择了数字温度传感器DS18B20来实现冰层温度梯度的检测。它的精度高、体积小、测量电路简单、可实现多点测量、价格低,而且可以在低温下可靠工作,能够满足本系统的要求,还可推广应用于一般小范围低温区域内的多点温度测量。在完成论文的过程中,基于空气、冰与水的电阻、温度特性差异设计制作了测量电阻值和温度值的实验室模型,实现了数据的自动采集与存储,节省了大量的人工操作。通过软件的方法实现用温度的变化来控制数据的采集与存储,改变了以前的定时采集存储数据的思路。使获得的数据比较合理,可用性强。进行了大量的实验室低温数据采集存储实验,结合实验中出现的问题进行了深入的理论分析。在实验模型的基础上设计制作了新的冰层厚度传感器,传感器的外型、选材、结构方面作了多项该进。模拟实际工作环境,对新的冰层厚度传感器进行了低温仿真实验,获得了大量的实验数据,为传感器性能的改进提供了科学理论和实践依据。新研制的冰层厚度传感器通过对冰层的多参数(电阻,温度)融合检测,测量精度与可靠性得到很大的提高,尤其是对下界面的区分比较明显,已经在第24次中国南极科学考察中实际使用,同时也为冰层厚度测报系统的进一步深入研究提供了新的理论依据和可供参考和借鉴的模式。更多还原

【Abstract】 This paper is an application foundation research which is aided by the item of national natural science fund "the research of the ice layer thickness sensor and its detecting method" (60672028). The ice layer thickness sensor based on the difference of resistance value among air> water and ice has been actually used in the 21st and the 22nd Chinese Antarctic Scientific Expedition. After analyzing a great deal of data which is obtained in the course of detecting Antarctic sea ice, we discover that the method using the difference of resistance value to measure sea ice thickness is comparatively precise in judging air-ice interface, but has some error in judging ice-water interface. Based on this result, the author of this paper proposed a new detecting method that using the characteristic difference of resistance and temperature to detect ice thickness, this new method is helpful to improve the precision of judging ice-water interface. At the same time, when the discrepancy of ice temperature and air temperature is comparatively wide, we can use the difference of temperature to judge air-ice interface, so the new method can improve the precision of judging above interface and realize multi-parameter detection. From the data obtained, we can analyze ice thickness, water level under ice and ice properties inside, it will help us to forecast ice layer’s change trend. So the research of this item has important scientific research value and practical application value.Through analyzing a quantity of earlier experimental data, we find the characteristic difference of resistance and temperature among air, water and ice. It provide us theory base of making sensor. After comparing all kinds of temperature sensors on sale, choose DS18B20 to realize multi-point temperature detecting. It has high precision, small volume, simple circuit, low price and can work under low temperature.We make a lab model which can collect and store data automatically. In this model, we use temperature’s change to control collecting and storing data, not time collecting and storing data. The data obtained is more reasonable and more usable. After a lot of lab’s low temperature experiments, combining with questions in using, the author analyzed the data deeply. Then, based on the model, we design and make new ice thickness sensor. The new sensor is improved from its shape, material to its structure according to actual working condition. Under similar working circumstance, we do low temperature experiments and acquired large numbers of data. The analysis of experimental data is good for improving sensor’s performance.Through multi-parameter (resistance, temperature) detecting, the new ice thickness sensor monitoring system has been actually used in the 24th Chinese Antarctic Scientific Expedition. The precision and reliability of the system has been improved significantly, especially the precision of judging ice-water interface. At the same time, this new method not only provided a new theory, but also supplied a reference model for further research on the ice thickness monitoring system.更多还原