柔性热膜质量流量传感器的制备与性能研究
发布时间：2019-06-21 02:39
【摘要】：航空飞行器表面气体流量的测量对部件本身的工作性能和使用寿命具有重大影响。它不仅提供了近壁流场的清晰诊断,显示层流或湍流特征,而且还与主动控制阻力直接相关。航空工业(例如飞行器机翼、航空发动机)对于流量传感器性能(尤其是器件的灵敏度,稳定性,测量范围等)具有非常高的要求。传统的测量方法存在干扰流场,测试精度低和响应速度慢等缺点,而柔性热膜质量流量传感器具有体积小、响应速度快,对流场无干扰等优点,对气体流量测量具有明显的优势。本文针对飞机机翼表面流量测量的需求,设计了一种柔性热膜质量流量传感器,开展了对热敏Ni薄膜制备工艺及电阻温度系数的研究,重点对柔性热膜质量流量传感器的灵敏度及标定进行探究。首先,利用ANSYS流体仿真软件对传感器模型尺寸进行设计:包括衬底厚度、热敏薄膜之间的间距尺寸。并对热敏电阻的大小、传感器排列方式和导线分布加以设计,结果表明:当热膜的间距一定,基底厚度越小、热量损失越小,测量结果越准确,故设定基底厚度为0.05mm;当气流速度一定时,随着相邻热敏电阻间距的增大,扩散的热量对彼此干扰越来越小,故设定热敏电阻的间距为2mm;当柔性热膜质量流量传感器的基底厚度和间距一定时,随着流速的增加,相邻热敏电阻的热量扩散相互干扰越小,更加有益于改善传感器的灵敏度。将电阻温度系数比较高的金属Ni作为热敏材料,绝热系数非常大的有机物聚酰亚胺(PI)作为基底,采用硬质掩膜版技术与微机电加工工艺技术结合的方法,制备出柔性热膜质量流量传感器。并对传感器制备工艺进行探究,在溅射功率为120W,氩气压强在0.6Pa,厚度为1μm时,测得比较高的电阻温度系数,其TCR值为4.41×10-3/℃。其次,采用风洞实验对柔性热膜质量流量传感器在不同气流速度下进行测量,结果表明:随着气流速度的增大,热敏电阻输出电压越大;当风速达到30m/s以上时,气流从层流状态向湍流过渡。在0~30m/s的气流速度下,对柔性热膜质量流量传感器进行标定,结果表明:气流速度与输出电压具有较好的线性度,柔性热膜质量流量传感器灵敏度较高,其灵敏度为0.388V/Pa,非线性度的误差在1.2%以下,可实现机翼表面气流在0~30m/s流速范围内的质量流量及剪切应力测量。
[Abstract]:The measurement of surface gas flow rate of aircraft has a great influence on the working performance and service life of the components themselves. It not only provides a clear diagnosis of the near-wall flow field and shows the characteristics of laminar flow or turbulence, but also is directly related to the active control resistance. The aviation industry (such as aircraft wings, aero-engines) has very high requirements for the performance of flow sensors (especially the sensitivity, stability, measurement range, etc.) of the devices. The traditional measurement method has some disadvantages, such as interference flow field, low test accuracy and slow response speed, while the flexible hot film mass flow sensor has the advantages of small volume, fast response speed and no interference to the flow field, so it has obvious advantages in gas flow measurement. In this paper, a flexible hot film mass flow sensor is designed to meet the needs of aircraft wing surface flow measurement. The preparation process and resistance temperature coefficient of thermistor Ni thin film are studied, with emphasis on the sensitivity and calibration of flexible hot film mass flow sensor. Firstly, the sensor model size is designed by ANSYS fluid simulation software, including substrate thickness and spacing size between thermosensory films. The size of thermistor, the arrangement of sensors and the distribution of conductors are designed. The results show that when the distance between hot film is certain, the smaller the thickness of substrate is, the smaller the heat loss is, the more accurate the measurement results are, so the thickness of substrate is set to be 0.05mm. When the air flow velocity is constant, with the increase of the distance between adjacent thermistors, the interference of diffusion heat to each other becomes smaller and smaller, so the distance between thermistors is set to be 2mm. When the thickness and spacing of the substrate of the flexible hot film mass flow sensor are fixed, with the increase of the flow rate, the smaller the thermal diffusion of the adjacent thermistors interferes with each other, the more beneficial to improve the sensitivity of the sensor. The flexible hot film mass flow sensor was prepared by using metal Ni with high resistance temperature coefficient as thermal sensitive material and organic polyimide (PI) with very large insulation coefficient as substrate. The flexible hot film mass flow sensor was prepared by combining hard mask technology with micro-electromechanical processing technology. The preparation technology of the sensor is studied. when the sputter power is 120W, the argon pressure is 0.6Paand the thickness is 1 渭 m, the high resistance temperature coefficient is measured, and the TCR value is 4.41 脳 10 ~ (- 3) / 鈩，
本文编号：2503719
[Abstract]:The measurement of surface gas flow rate of aircraft has a great influence on the working performance and service life of the components themselves. It not only provides a clear diagnosis of the near-wall flow field and shows the characteristics of laminar flow or turbulence, but also is directly related to the active control resistance. The aviation industry (such as aircraft wings, aero-engines) has very high requirements for the performance of flow sensors (especially the sensitivity, stability, measurement range, etc.) of the devices. The traditional measurement method has some disadvantages, such as interference flow field, low test accuracy and slow response speed, while the flexible hot film mass flow sensor has the advantages of small volume, fast response speed and no interference to the flow field, so it has obvious advantages in gas flow measurement. In this paper, a flexible hot film mass flow sensor is designed to meet the needs of aircraft wing surface flow measurement. The preparation process and resistance temperature coefficient of thermistor Ni thin film are studied, with emphasis on the sensitivity and calibration of flexible hot film mass flow sensor. Firstly, the sensor model size is designed by ANSYS fluid simulation software, including substrate thickness and spacing size between thermosensory films. The size of thermistor, the arrangement of sensors and the distribution of conductors are designed. The results show that when the distance between hot film is certain, the smaller the thickness of substrate is, the smaller the heat loss is, the more accurate the measurement results are, so the thickness of substrate is set to be 0.05mm. When the air flow velocity is constant, with the increase of the distance between adjacent thermistors, the interference of diffusion heat to each other becomes smaller and smaller, so the distance between thermistors is set to be 2mm. When the thickness and spacing of the substrate of the flexible hot film mass flow sensor are fixed, with the increase of the flow rate, the smaller the thermal diffusion of the adjacent thermistors interferes with each other, the more beneficial to improve the sensitivity of the sensor. The flexible hot film mass flow sensor was prepared by using metal Ni with high resistance temperature coefficient as thermal sensitive material and organic polyimide (PI) with very large insulation coefficient as substrate. The flexible hot film mass flow sensor was prepared by combining hard mask technology with micro-electromechanical processing technology. The preparation technology of the sensor is studied. when the sputter power is 120W, the argon pressure is 0.6Paand the thickness is 1 渭 m, the high resistance temperature coefficient is measured, and the TCR value is 4.41 脳 10 ~ (- 3) / 鈩，
本文编号：2503719
本文链接：https://www.wllwen.com/kejilunwen/zidonghuakongzhilunwen/2503719.html
