WindSonic – a new ultrasonic anemometer

Sensor Review ◽  
2002 ◽  
Vol 22 (3) ◽  
pp. 218-222 ◽  
Author(s):  
Chris Stock
Keyword(s):  
Wind Speed ◽  
Time Of Flight ◽  
Operating Principle ◽  
Air Velocity ◽  
Vector Measurement ◽  
Ultrasonic Technology ◽  
Ultrasonic Anemometer ◽  
Air Speed

Describes the developments of a small, robust ultrasonic wind speed and direction indicator. Gill’s patented ultrasonic technology is based on the time‐of‐flight operating principle, which provides vector measurement of air velocity, given the dimensions and geometry of pairs of transducers. In this case, two pairs of transducers are used such that the air velocity can be derived along orthogonal axes and hence the air speed and direction can be computed.

scholarly journals PENGARUH BUKAAN SAMPING (CLERESTORY) TERHADAP KUALITAS KENYAMANAN TERMAL PADA FOOD CARNIVAL, MALL AEON BSD

Vitruvian ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 47
Author(s):  
Tathia Edra Swasti
Keyword(s):  
Wind Speed ◽  
Thermal Comfort ◽  
Air Temperature ◽  
Effective Temperature ◽  
Air Humidity ◽  
Air Velocity ◽  
Predicted Mean Vote ◽  
Air Speed ◽  
The Right

ABSTRAK Mall saat ini marak menggunakan clerestory sebagai salah satu upaya untuk penerangan alami pada siang hari. Namun, cahaya matahari pada sore hari (barat) akan menghasilkan cahaya matahari yang lebih panas dan silau dibandingkan cahaya matahari pada pagi hari (timur). Oleh karena itu, dengan pemakaian clerestory yang cukup besar pada bangunan, masalah panas tentu tak dapat dihindari. Begitu pula dengan glare yang berasal dari pantulan sinar matahari. Salah satu Mall yang menggunakan clerestory adalah Mall AEON BSD. Pengukuran suhu udara, temperatur efektif, kelembaban udara, kecepatan angin, PMV (Predicted Mean Vote) dan PPD (Predicted Percentage of Dissatisfied) dilaksanakan pada 4 waktu dengan 5 lokasi titik ukur yang memiliki kondisi berbeda untuk membuktikan bahwa clerestory dapat mempengaruhi kenyamanan termal. Disimpulkan bahwa titik 2 yaitu titik yang berdekatan dengan clerestory sisi kanan (ukurannya lebih kecil daripada clerestory sisi kiri) memiliki temperatur efektif dan kelembaban udara yang lebih rendah dari titik lain, dan kecepatan udara (dipengaruhi oleh hembusan AC) lebih tinggi dari titik lain. Responden merasa nyaman saat berada di titik tersebut.Titik paling nyaman menurut responden adalah titik 2 dengan TE rata-rata berkisar 27,4˚C, kelembaban udara rata-rata berkisar 52,2%, kecepatan udara rata-rata berkisar 0,15 m/s, PMV berkisar 0,5 dan PPD berkisar 12,7%. Dengan begitu semakin kecil ukuran skylight terbukti mempengaruhi kenyamanan termal dan membuat kenyamanan termal dapat tercapai. Kata Kunci: Mall, Clerestory, PMV, PPD, Kenyamanan Termal ABSTRACT Nowadays mall is decorated with clerestory as an effort to lighten naturally during the day. However, sunlight in the afternoon (west) will produce more sunlight and glare than sunlight in the morning (east). Therefore, with the use of a fairly large clerestory in buildings, the problem of heat certainly can not be avoided. Similarly, glare that comes from the reflection of sunlight. One of the malls that use clerestory is BSD AEON Mall. Measurement of air temperature, effective temperature, air humidity, wind speed, PMV (Predicted Mean Vote) and PPD (Predicted Percentage of Dissatisfied) carried out at 4 times within 5 measuring spots that have different conditions, proving that clerestory can affect thermal comfort. It was concluded that point 2, which is the point adjacent to the right side clerestory (smaller in size than the left side clerestory) has an effective temperature and lower air humidity than other points, and air velocity (affected by blowing AC) is higher than other points. Respondents felt comfortable when they were at that point. The most comfortable point according to respondents was point 2 with TE averaging around 27.4˚C, air humidity averaged 52.2%, the average air speed ranged from 0.15 m / s, PMV ranges from 0.5 and PPD ranges from 12.7%. Thus, the smaller size of the clerestory is affecting thermal comfort and thermal comfort can be achieved. Keywords: Mall, Clerestory, PMV, PPD, Thermal Comfort

scholarly journals Towards accurate and practical drone-based wind measurements with an ultrasonic anemometer

2021 ◽  
Vol 14 (2) ◽  
pp. 1303-1318
Author(s):  
William Thielicke ◽  
Waldemar Hübert ◽  
Ulrich Müller ◽  
Michael Eggert ◽  
Paul Wilhelm
Keyword(s):  
Wind Speed ◽  
Wind Tunnel ◽  
Sonic Anemometer ◽  
Substantial Reduction ◽  
Three Dimensional ◽  
Cost Effective ◽  
Single Location ◽  
Ultrasonic Anemometer ◽  
Induced Flow ◽  
Air Speed

Abstract. Wind data collection in the atmospheric boundary layer benefits from short-term wind speed measurements using unmanned aerial vehicles. Fixed-wing and rotary-wing devices with diverse anemometer technology have been used in the past to provide such data, but the accuracy still has the potential to be increased. A lightweight drone for carrying an industry-standard precision sonic anemometer was developed. Accuracy tests have been performed with the isolated anemometer at high tilt angles in a calibration wind tunnel, with the drone flying in a large wind tunnel and with the full system flying at different heights next to a bistatic lidar reference. The propeller-induced flow deflects the air to some extent, but this effect is compensated effectively. The data fusion shows a substantial reduction of crosstalk (factor of 13) between ground speed and wind speed. When compared with the bistatic lidar in very turbulent conditions, with a 10 s averaging interval and with the unmanned aerial vehicle (UAV) constantly circling around the measurement volume of the lidar reference, wind speed measurements have a bias between −2.0 % and 4.2 % (root-mean-square error (RMSE) of 4.3 % to 15.5 %), vertical wind speed bias is between −0.05 and 0.07 m s−1 (RMSE of 0.15 to 0.4 m s−1), elevation bias is between −1 and 0.7∘ (RMSE of 1.2 to 6.3∘), and azimuth bias is between −2.6 and 7.2∘ (RMSE of 2.6 to 8.0∘). Key requirements for good accuracy under challenging and dynamic conditions are the use of a full-size sonic anemometer, a large distance between anemometer and propellers, and a suitable algorithm for reducing the effect of propeller-induced flow. The system was finally flown in the wake of a wind turbine, successfully measuring the spatial velocity deficit and downwash distribution during forward flight, yielding results that are in very close agreement to lidar measurements and the theoretical distribution. We believe that the results presented in this paper can provide important information for designing flying systems for precise air speed measurements either for short duration at multiple locations (battery powered) or for long duration at a single location (power supplied via cable). UAVs that are able to accurately measure three-dimensional wind might be used as a cost-effective and flexible addition to measurement masts and lidar scans.

scholarly journals Towards accurate and practical drone-based wind measurements with an ultrasonic anemometer

2020 ◽  
Author(s):  
William Thielicke ◽  
Waldemar Hübert ◽  
Ulrich Müller
Keyword(s):  
Wind Speed ◽  
Wind Tunnel ◽  
Sonic Anemometer ◽  
Three Dimensional ◽  
Cost Effective ◽  
Industry Standard ◽  
Single Location ◽  
Ultrasonic Anemometer ◽  
Absolute Bias ◽  
Air Speed

Abstract. Wind data collection in the atmospheric boundary layer benefits from short term wind speed measurements using unmanned aerial vehicles. Fixed and rotary wing devices with diverse anemometer technology have been used in the past to provide such data, but the accuracy still has the potential to be increased. We developed a light weight drone (weight including sensor  45 min) for carrying an industry standard precision sonic anemometer. Accuracy tests have been performed with the isolated anemometer at high tilt angles in a calibration wind tunnel, with the drone flying in a large wind tunnel, and with the full system flying at different heights next to a bistatic lidar reference. The propeller-induced flow deflects the air to some extent, but this effect is compensated effectively. Our data fusion shows no signs of crosstalk between ground speed and wind speed. When compared with the bistatic lidar in very turbulent conditions, with 10 seconds averaging interval and with the UAV constantly circling around the measurement volume of the lidar reference, wind speed measurements have an average absolute bias of 1.9 % (0.073 m s−1), wind elevation average absolute bias is 0.5°, and wind azimuth average absolute bias is 1.5°, indicating excellent accuracy under challenging and dynamic conditions. The system was finally flown in the wake of a wind turbine, successfully measuring the spatial velocity deficit distribution during forward flight, yielding results that are in very close agreement to lidar measurements and the theoretical distribution. We believe that the results presented in this paper can provide important information for designing flying systems for precise air speed measurements either for short duration at multiple locations (battery powered) or for long duration at a single location (power supplied via cable). UAVs that are able to accurately measure three-dimensional wind might be used as cost effective and flexible addition to measurement masts and lidar scans.

scholarly journals An Optimized Flutter-Driven Triboelectric Nanogenerator with a Low Cut-In Wind Speed

Micromachines ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 366
Author(s):  
Yang Xia ◽  
Yun Tian ◽  
Lanbin Zhang ◽  
Zhihao Ma ◽  
Huliang Dai ◽  
...  
Keyword(s):  
Power Generation ◽  
Wind Speed ◽  
Energy Harvesting ◽  
Wind Energy ◽  
Output Power ◽  
Open Circuit Voltage ◽  
Open Circuit ◽  
Triboelectric Nanogenerator ◽  
Vibration Behavior ◽  
Air Speed

We present an optimized flutter-driven triboelectric nanogenerator (TENG) for wind energy harvesting. The vibration and power generation characteristics of this TENG are investigated in detail, and a low cut-in wind speed of 3.4 m/s is achieved. It is found that the air speed, the thickness and length of the membrane, and the distance between the electrode plates mainly determine the PTFE membrane’s vibration behavior and the performance of TENG. With the optimized value of the thickness and length of the membrane and the distance of the electrode plates, the peak open-circuit voltage and output power of TENG reach 297 V and 0.46 mW at a wind speed of 10 m/s. The energy generated by TENG can directly light up dozens of LEDs and keep a digital watch running continuously by charging a capacitor of 100 μF at a wind speed of 8 m/s.

Experimental and Theoretical Investigation of Performance of a Solar Chimney Model, Part I: Experimental Investigation

2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Essaied M Shuia ◽  
Bashir H Arebi ◽  
Ibrahim A abuashe
Keyword(s):  
Experimental Data ◽  
Wind Speed ◽  
Solar Radiation ◽  
Air Temperature ◽  
Solar Collector ◽  
Experimental Results ◽  
Internal Diameter ◽  
Solar Chimney ◽  
Air Velocity ◽  
Collector Temperature

This paper presents the experimental data that was collected from small pilot solar chimney. The experimental data together with ambient conditions are used to evaluate the performance and study the behavior of the solar chimney; this data will be used for comparison with theoretical models in another paper [part II). The solar chimney prototype was designed and constructed at the Subrata Faculty of Engineering-Libya. The data were collected over several days of June 2011. The solar chimney system contains two main components; the solar collector and the solar chimney. The solar collector root‘ has a circular area of126 m3, the solar chimney is a PVC tube with internal diameter of 0.2 m and the total height of chimney is 9.3 m. The measurements include the intensity of solar radiation inside/outside the collector, temperature and velocity of air at the entrance of the chimney, temperature and speed of wind outside the collector, temperature of the ground inside collector al1d temperature measurements of air at speci?c points at different levels throughout the collector. Solar irradiance was found to affect the chimney temperature and subsequently affects chimney air velocity. The experimental results showed that temperature differences of (30 - 45°C) were recorded between the ambient temperature and that of air inside the chimney in the middle of the day, where the highest air temperature of 73.4°C was recorded at the entrance of the solar chimney. The maximum air velocity of 3.6 m/s was recorded inside the solar chimney at noon on 9 June. Wind speed outside the collector had a small effect on the speed of the air inside the chimney and tends to change slightly, hence, can neglect influence of wind speed on the performance of the system. Also the experimental results indicate that such type of system can trap a suf?cient amount of solar radiation, which elevates the air temperature to a suf?cient value able to generate enough air ?ow to operate a wind turbine to produce electricity; this means the solar chimney system for electricity production can work in the north-western part of Libya in the summer time at least.

Optimization of a Biomass Micro-Gasification Process for the Production of Synthesis Gas From Palm Shell

2015 ◽  
Author(s):  
Luz M. Ahumada ◽  
Arnaldo Verdeza ◽  
Antonio J. Bula
Keyword(s):  
Particle Size ◽  
Fixed Bed ◽  
High Energy ◽  
Operating Conditions ◽  
Air Velocity ◽  
Output Variable ◽  
Heating Value ◽  
Palm Shell ◽  
Gasification Process ◽  
Air Speed

This paper studied, through an experiment design, the significance of particle size, air speed and reactor arrangement for palm shell micro-gasification process in order to optimize the heating value of the syngas obtained. The range of variables was 8 to 13 mm for particle size, 0.8–1.4m/s for air velocity, and updraft or downdraft for the reactor type. It was found that the particle size and air velocity factors were the most significant in the optimization of the output variable, syngas heating value. A heating value of 2.69MJ / Nm3 was obtained using a fixed bed downdraft reactor, with a particle size of 13 mm and 1.4 m/s for air speed; verification of the optimum point of operation under these conditions verified that these operating conditions favor the production of a gas with a high energy value.

scholarly journals Reviewing Wind Measurement Approaches for Fixed-Wing Unmanned Aircraft

Atmosphere ◽  
2018 ◽  
Vol 9 (11) ◽  
pp. 422 ◽  
Author(s):  
Alexander Rautenberg ◽  
Martin Graf ◽  
Norman Wildmann ◽  
Andreas Platis ◽  
Jens Bange
Keyword(s):  
Wind Speed ◽  
Unmanned Aircraft ◽  
Flow Sensor ◽  
Navigation Satellite ◽  
Wind Vector ◽  
Data Set ◽  
Vector Measurement ◽  
Wide Range ◽  
Global Navigation ◽  
Global Navigation Satellite

One of the biggest challenges in probing the atmospheric boundary layer with small unmanned aerial vehicles is the turbulent 3D wind vector measurement. Several approaches have been developed to estimate the wind vector without using multi-hole flow probes. This study compares commonly used wind speed and direction estimation algorithms with the direct 3D wind vector measurement using multi-hole probes. This was done using the data of a fully equipped system and by applying several algorithms to the same data set. To cover as many aspects as possible, a wide range of meteorological conditions and common flight patterns were considered in this comparison. The results from the five-hole probe measurements were compared to the pitot tube algorithm, which only requires a pitot-static tube and a standard inertial navigation system measuring aircraft attitude (Euler angles), while the position is measured with global navigation satellite systems. Even less complex is the so-called no-flow-sensor algorithm, which only requires a global navigation satellite system to estimate wind speed and wind direction. These algorithms require temporal averaging. Two averaging periods were applied in order to see the influence and show the limitations of each algorithm. For a window of 4 min, both simplifications work well, especially with the pitot-static tube measurement. When reducing the averaging period to 1 min and thereby increasing the temporal resolution, it becomes evident that only circular flight patterns with full racetracks inside the averaging window are applicable for the no-flow-sensor algorithm and that the additional flow information from the pitot-static tube improves precision significantly.

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