In order to consider the influence of steel pole on the measurement of wind speed sensors and determinate the installation position of wind speed sensors, the flow field around wind speed sensors was investigated. Bas...In order to consider the influence of steel pole on the measurement of wind speed sensors and determinate the installation position of wind speed sensors, the flow field around wind speed sensors was investigated. Based on the three-dimensional steady Reynolds-averaged Navier-Stokes equations and k-ε double equations turbulent model, the field flow around the wind speed sensor and the steel pole along a high-speed railway was simulated on an unstructured grid. The grid-independent validation was conducted and the accuracy of the present numerical simulation method was validated by experiments and simulations carried out by previous researchers. Results show that the steel pole has a significant influence on the measurement results of wind speed sensors. As the distance between two wind speed sensors is varied from 0.3 to 1.0 m, the impact angles are less than ±20°, it is proposed that the distance between two wind speed sensors is 0.8 m at least, and the interval between wind speed sensors and the steel pole is more than 1.0 m with the sensors located on the upstream side.展开更多
According to the verification regulation of the Wind Direction and Wind Speed Sensor of Automatic Meteorological Station[JJG(meteorological)004-2011],relying on the wind tunnel laboratory of Hebei meteorological measu...According to the verification regulation of the Wind Direction and Wind Speed Sensor of Automatic Meteorological Station[JJG(meteorological)004-2011],relying on the wind tunnel laboratory of Hebei meteorological measurement station,EL15-1 A type of wind speed sensor in the automatic weather station was verified.The experimental data of sensor verification in different laboratory environments were obtained through data comparison.Using standard wind speed measurement formula,the influence of laboratory temperature,humidity and air pressure on verification results was analyzed quantitatively.The results showed that laboratory temperature had the greatest influence on the verification results of this type of sensor,while the humidity and air pressure had less influence.Therefore,it should be noted that the temperature change in the laboratory should not be too large in the process of verification,so as to improve the accuracy of the verification results.展开更多
The early warning and monitoring of gale disasters are very important for the safety of people’s lives and properties. Triboelectric nanogenerators(TENGs) are popular for wind speed sensors due to their self-powered ...The early warning and monitoring of gale disasters are very important for the safety of people’s lives and properties. Triboelectric nanogenerators(TENGs) are popular for wind speed sensors due to their self-powered property. However, a TENG cannot easily work at low wind speeds due to the limitation of the high frictional resistance structure. In this paper, a TENG-based breezeactivated wind speed sensor(BAWS) with an ultra-low frictional resistance is proposed. The key drive unit of the BAWS is a Savonius-like vertical axis wind turbine, which is fabricated by arrayed airfoil profile blades with excellent flow field characteristics. Here a wind turbine plays dual roles in driving the electromagnetic generator below it to supply energy and lead the TENG above it to sense the wind force. Compared to a classical turbine with a wind cup, the designed turbine has a low resistance torque. The synergistic effect of the drive unit with low-resistance and triboelectric materials with low viscosity allows the BAWS to be activated even at a wind speed of 2.9 m/s. The sensitivities of the voltage frequency and current amplitude of the TENG are used to reflect the electrical property of the BAWS. The measured values are 0.291 Hz/(m·s-1) and 0.221 μA/(m·s-1),which reflects the good sensitivity of the BAWS. Moreover, the linearity of the BAWS reaches up to 0.991, which shows an accurate output for the wind speed. In addition, the device is equipped with a combined electromagnetic-solar unit as the sole power source to meet the sensor’s all-weather operation requirements. This work expands the application prospects of selfpowered sensing technology in the field of disaster warning.展开更多
In most areas of China, affected by the environment of low temperature and high humidity, the wind speed sensor and wind direction sensor are frozen and cannot output data in autumn, winter or the alternation of winte...In most areas of China, affected by the environment of low temperature and high humidity, the wind speed sensor and wind direction sensor are frozen and cannot output data in autumn, winter or the alternation of winter and spring. In order to solve the freezing situation of the wind sensor, this paper designs a new type of antifreeze wind speed sensor. After meteorology performance testing and field observation tests, the correlation coefficient of the observation data is demonstrated, and the data curve is fitted. The result shows the sensor is stable, and has a good antifreeze effect, the data output is reliable.展开更多
在风速传感器实测风速不确定度的评定中,传统方法是将实测风速测量模型简化后采用GUM(guide to the expression uncertainty in measurement)进行评定。但GUM并不适用于复杂模型,为了研究实测风速不确定度评定的可靠方法,对风速传感器...在风速传感器实测风速不确定度的评定中,传统方法是将实测风速测量模型简化后采用GUM(guide to the expression uncertainty in measurement)进行评定。但GUM并不适用于复杂模型,为了研究实测风速不确定度评定的可靠方法,对风速传感器分别采用GUM和MCM(Monte Carlo method)进行不确定度评定,对比分析评定结果,并利用MCM评定结果验证GUM的适用性。结果表明,简化模型下GUM和MCM评定结果差异较小,但只有标准不确定度取一位有效数字时,GUM评定方法通过验证,评定结果一致性好;实测模型下MCM和简化模型下GUM评定结果对比得到,两者包络形状相似,但实测风速最佳估计值明显偏大,GUM评定方法不能通过验证;改变部分输入量分布时,两种方法得到实测风速最佳估计值非常接近,但GUM评定得到包含区间比MCM明显增宽,概率分布相差较大,GUM评定方法不能通过验证。因此,应当根据模型的复杂程度、输入量分布情况以及测量结果准确度的要求选择合适的评定方法,如果输入量分布均服从正态分布且对测量准确度要求不高,可使用GUM进行评定,反之建议使用MCM评定以提高观测结果的准确性和可靠性。展开更多
基金Projects(U1334205,51205418)supported by the National Natural Science Foundation of ChinaProject(2014T002-A)supported by the Science and Technology Research Program of China Railway CorporationProject(132014)supported by the Fok Ying Tong Education Foundation of China
文摘In order to consider the influence of steel pole on the measurement of wind speed sensors and determinate the installation position of wind speed sensors, the flow field around wind speed sensors was investigated. Based on the three-dimensional steady Reynolds-averaged Navier-Stokes equations and k-ε double equations turbulent model, the field flow around the wind speed sensor and the steel pole along a high-speed railway was simulated on an unstructured grid. The grid-independent validation was conducted and the accuracy of the present numerical simulation method was validated by experiments and simulations carried out by previous researchers. Results show that the steel pole has a significant influence on the measurement results of wind speed sensors. As the distance between two wind speed sensors is varied from 0.3 to 1.0 m, the impact angles are less than ±20°, it is proposed that the distance between two wind speed sensors is 0.8 m at least, and the interval between wind speed sensors and the steel pole is more than 1.0 m with the sensors located on the upstream side.
文摘According to the verification regulation of the Wind Direction and Wind Speed Sensor of Automatic Meteorological Station[JJG(meteorological)004-2011],relying on the wind tunnel laboratory of Hebei meteorological measurement station,EL15-1 A type of wind speed sensor in the automatic weather station was verified.The experimental data of sensor verification in different laboratory environments were obtained through data comparison.Using standard wind speed measurement formula,the influence of laboratory temperature,humidity and air pressure on verification results was analyzed quantitatively.The results showed that laboratory temperature had the greatest influence on the verification results of this type of sensor,while the humidity and air pressure had less influence.Therefore,it should be noted that the temperature change in the laboratory should not be too large in the process of verification,so as to improve the accuracy of the verification results.
基金supported by the National Natural Science Foundation of China (Grant Nos. 51975542, 62101513, and 62171414)Young Academic Leaders Project of North University of China (Grant No. 11045501)。
文摘The early warning and monitoring of gale disasters are very important for the safety of people’s lives and properties. Triboelectric nanogenerators(TENGs) are popular for wind speed sensors due to their self-powered property. However, a TENG cannot easily work at low wind speeds due to the limitation of the high frictional resistance structure. In this paper, a TENG-based breezeactivated wind speed sensor(BAWS) with an ultra-low frictional resistance is proposed. The key drive unit of the BAWS is a Savonius-like vertical axis wind turbine, which is fabricated by arrayed airfoil profile blades with excellent flow field characteristics. Here a wind turbine plays dual roles in driving the electromagnetic generator below it to supply energy and lead the TENG above it to sense the wind force. Compared to a classical turbine with a wind cup, the designed turbine has a low resistance torque. The synergistic effect of the drive unit with low-resistance and triboelectric materials with low viscosity allows the BAWS to be activated even at a wind speed of 2.9 m/s. The sensitivities of the voltage frequency and current amplitude of the TENG are used to reflect the electrical property of the BAWS. The measured values are 0.291 Hz/(m·s-1) and 0.221 μA/(m·s-1),which reflects the good sensitivity of the BAWS. Moreover, the linearity of the BAWS reaches up to 0.991, which shows an accurate output for the wind speed. In addition, the device is equipped with a combined electromagnetic-solar unit as the sole power source to meet the sensor’s all-weather operation requirements. This work expands the application prospects of selfpowered sensing technology in the field of disaster warning.
文摘In most areas of China, affected by the environment of low temperature and high humidity, the wind speed sensor and wind direction sensor are frozen and cannot output data in autumn, winter or the alternation of winter and spring. In order to solve the freezing situation of the wind sensor, this paper designs a new type of antifreeze wind speed sensor. After meteorology performance testing and field observation tests, the correlation coefficient of the observation data is demonstrated, and the data curve is fitted. The result shows the sensor is stable, and has a good antifreeze effect, the data output is reliable.
文摘在风速传感器实测风速不确定度的评定中,传统方法是将实测风速测量模型简化后采用GUM(guide to the expression uncertainty in measurement)进行评定。但GUM并不适用于复杂模型,为了研究实测风速不确定度评定的可靠方法,对风速传感器分别采用GUM和MCM(Monte Carlo method)进行不确定度评定,对比分析评定结果,并利用MCM评定结果验证GUM的适用性。结果表明,简化模型下GUM和MCM评定结果差异较小,但只有标准不确定度取一位有效数字时,GUM评定方法通过验证,评定结果一致性好;实测模型下MCM和简化模型下GUM评定结果对比得到,两者包络形状相似,但实测风速最佳估计值明显偏大,GUM评定方法不能通过验证;改变部分输入量分布时,两种方法得到实测风速最佳估计值非常接近,但GUM评定得到包含区间比MCM明显增宽,概率分布相差较大,GUM评定方法不能通过验证。因此,应当根据模型的复杂程度、输入量分布情况以及测量结果准确度的要求选择合适的评定方法,如果输入量分布均服从正态分布且对测量准确度要求不高,可使用GUM进行评定,反之建议使用MCM评定以提高观测结果的准确性和可靠性。
