Study of Dispersion Hazard Potential of The LPG Stations  Around the RDE Site in Rainy and Dry Season

STUDY OF DISPERSION HAZARD POTENTIAL OF THE LPG STATIONS AROUND THE RDE SITE IN RAINY AND DRY SEASON. There are two LPG station (SPPBE) which are the depot of filling, storage and distribution of Liquid Petroleum Gas (LPG) namely PT. BM and PT. ISR which the distance each are 2,995 and 4,141 km from Experimental Power Reactor (RDE) site with capacity 15 and 30 tons. LPG station is a stationary source, which is one aspect of the external human induced events that need to be analyzed in the preparation of site evaluation reports to obtain site permits. Hazard potential that may occur from the depot LPG are fire, explosion and dispersion of hazardous and toxic gas. The release of LPG due to valve leakage which is then dispersed at a certain dose has potentially harmful to health, even death to the population around the RDE site. The purpose of the study was to know the effect of seasons (rainy and dry) to the potential hazard of LPG dispersion from LPG truck tank valve to the around RDE site. The method of study are collection the atmospheric data such as wind direction and speed, temperature and humidity, collection the station LPG characteristic, such as mass of gas, diameter and length of tank, and valve diameter, etc. The atmospheric data was obtained from Pondok Betung Climatology Station, in dry, transition, and rainy seasons, furthermore data was analyzed using ALOHA software version 5.4.5. The results show dispersion from LPG release due to valve leakage from PT. BM and PT. ISR around the RDE site, in the dry season (April), the transition (January and July) as well as the rainy season (October) does not hazardous to the RDE site. Maximum threat zone occurs in dry season at April (wind speed 1.54 m/s), which reaches radius 179 m with airborne LPG concentration 5500 ppm, radius 111 m with concentration 17000 ppm and radius 71 m with concentration 53000 ppm.

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Wind Shear of Low-Level Jets and Their Influence on Manned and Unmanned Fixed-Wing Aircraft during Landing Approach

Atmosphere ◽

10.3390/atmos13010035 ◽

2021 ◽

Vol 13 (1) ◽

pp. 35

Author(s):

Lutz Bretschneider ◽

Rudolf Hankers ◽

Shanna Schönhals ◽

Jens-Michael Heimann ◽

Astrid Lampert

Keyword(s):

Wind Speed ◽

Flight Control ◽

Wind Direction ◽

Wind Shear ◽

Speed Ratio ◽

Mountain Range ◽

Potential Hazard ◽

Low Level ◽

Anticlockwise Direction ◽

Low Level Jets

Wind shear at low altitudes represents a potential hazard to landing aircraft. Based on two wind lidar data sets of one year, the occurrence of low-level jets (LLJs), the vertical wind shear and the rotation of the wind direction were analysed. The lidar system was located at the sites of Braunschweig in the North German Plain, Germany, and Clausthal-Zellerfeld in the low mountain range Harz, Germany. The observed wind shear gradients between the altitude of 40 m and the altitude of the maximum wind speed was in the range of −0.23 s−1 to +0.20 s−1. The rotation of the wind direction with altitude occurred both in clockwise and anticlockwise direction. The ratio of clockwise versus anticlockwise occurrence of directional shear was 4:1 for Braunschweig and 3:1 for Clausthal-Zellerfeld. The observed wind shear gradients were compared to values for hazard potential of different levels for a typical aircraft. Although the LLJ was not hazardous for manned aircraft in any observed case, the awareness of LLJ helps to reduce the pilot’s workload and possible pilot-introduced oscillations caused as a result of the wind shear and aircraft characteristics. In contrast to manned aviation, the value of changes in wind speed and direction during LLJ conditions can cause significant risks for unmanned aerial system operations with less than 25 kg of take-off weight. This is a result of the lower airspeed-wind-speed ratio and the flight control and flight planning.

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2.5D Flexible Wind Sensor Using Differential Plate Capacitors

Sensors ◽

10.3390/s21093101 ◽

2021 ◽

Vol 21 (9) ◽

pp. 3101

Author(s):

Yu Wan ◽

Zhenxiang Yi

Keyword(s):

Wind Speed ◽

Wind Direction ◽

Parallel Plate ◽

Electrode Array ◽

Copper Electrode ◽

Windward Side ◽

Leeward Side ◽

Electrode Layer ◽

Young’S Moduli ◽

Speed Up

In this paper, a novel 2.5-dimensional (2.5D) flexible wind sensor is proposed based on four differential plate capacitors. This design consists of a windward pillar, two electrode layers, and a support layer, which are all made of polydimethylsiloxane (PDMS) with different Young’s moduli. A 2 mm × 2 mm copper electrode array is located on each electrode layer, forming four parallel plate capacitors as the sensitive elements. The wind in the xy-plane tilts the windward pillar, decreasing two capacitances on the windward side and increasing two capacitances on the leeward side. The wind in the z-axis depresses the windward pillar, resulting in an increase of all four capacitances. Experiments demonstrate that this sensor can measure the wind speed up to 23.9 m/s and the wind direction over the full 360° range of the xy-plane. The sensitivities of wind speed are close to 4 fF·m−1·s and 3 fF·m−1·s in the xy-plane and z-axis, respectively.

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Movement of Large Convective Rainstorms in Relation to Winds Aloft

Bulletin of the American Meteorological Society ◽

10.1175/1520-0477-39.3.129 ◽

1958 ◽

Vol 39 (3) ◽

pp. 129-136 ◽

Cited By ~ 27

Author(s):

C. W. Newton ◽

Sey Katz

Keyword(s):

Wind Speed ◽

Wind Direction ◽

Rainfall Data ◽

Squall Lines ◽

Hourly Rainfall ◽

The Difference ◽

Strong Winds

By means of hourly rainfall data from the Hydroclimatic Network, the motions of large rainstorms, of the kind associated with squall lines, are examined in relation to the winds aloft. Very little correlation is found between the speed of movement of the rainstorms and the wind speed at any level, although the fastest moving storms were associated with strong winds aloft. Significant correlation is found between direction of motion of rainstorms, and wind direction at 700 mb or higher levels. On the average, the rainstorms move with an appreciable component toward right of the wind direction. The difference between these results, and those from other studies based on small precipitation areas, is ascribed to propagation. The mechanism involved is discussed briefly.

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Surface gas pollutants in Lhasa, a highland city of Tibet – current levels and pollution implications

Atmospheric Chemistry and Physics ◽

10.5194/acp-14-10721-2014 ◽

2014 ◽

Vol 14 (19) ◽

pp. 10721-10730 ◽

Cited By ~ 20

Author(s):

L. Ran ◽

W. L. Lin ◽

Y. Z. Deji ◽

B. La ◽

P. M. Tsering ◽

...

Keyword(s):

Wind Speed ◽

Wind Direction ◽

Fossil Fuels ◽

Trace Gases ◽

Early Morning ◽

Current Status ◽

Urban Site ◽

Large Variability ◽

Mixing Ratios ◽

Low Wind Speed

Abstract. Through several years of development, the city of Lhasa has become one of the most populated and urbanized areas on the highest plateau in the world. In the process of urbanization, current and potential air quality issues have been gradually concerned. To investigate the current status of air pollution in Lhasa, various gas pollutants including NOx, CO, SO2, and O3, were continuously measured from June 2012 to May 2013 at an urban site (29.40° N, 91.08° E, 3650 m a.s.l.). The seasonal variations of primary gas pollutants exhibited a peak from November to January with a large variability. High mixing ratios of primary trace gases almost exclusively occurred under low wind speed and showed no distinct dependence on wind direction, implying local urban emissions to be predominant. A comparison of NO2, CO, and SO2 mixing ratios in summer between 1998 and 2012 indicated a significant increase in emissions of these gas pollutants and a change in their intercorrelations, as a result of a substantial growth in the demand of energy consumption using fossil fuels instead of previously widely used biomass. The pronounced diurnal double peaks of primary trace gases in all seasons suggested automobile exhaust to be a major emission source in Lhasa. The secondary gas pollutant O3 displayed an average diurnal cycle of a shallow flat peak for about 4–5 h in the afternoon and a minimum in the early morning. Nighttime O3 was sometimes completely consumed by the high level of NOx. Seasonally, the variations of O3 mixing ratios displayed a low valley in winter and a peak in spring. In autumn and winter, transport largely contributed to the observed O3 mixing ratios, given its dependence on wind speed and wind direction, while in spring and summer photochemistry played an important role. A more efficient buildup of O3 mixing ratios in the morning and a higher peak in the afternoon was found in summer 2012 than in 1998. An enhancement in O3 mixing ratios would be expected in the future and more attention should be given to O3 photochemistry in response to increasing precursor emissions in this area.

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Numerical Investigation of Thermal Flow Field of Air-Cooled Condensers for Yongshou Plant

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.248.391 ◽

2012 ◽

Vol 248 ◽

pp. 391-394

Author(s):

Wen Zhou Yan ◽

Wan Li Zhao ◽

Qiu Yan Li

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Wind Speed ◽

Power Plant ◽

Flow Field ◽

Wind Direction ◽

Rotational Speed ◽

Power Plants ◽

Thermal Flow ◽

Air Cooled Condensers

By using the computational fluid dynamics code, FLUENT, Numerically simulation is investigated for Youngshou power plant. Under the constant ambient temperature, the effects of different wind speed and wind direction on the thermal flow field are qualitatively considered. It was found that when considering about the existing and normally operating power plants, the thermal flow field is more sensitive to wind direction and wind speed. Based on the above results, three improved measures such as: increasing the wind-wall height and accelerating the rotational speed of the fans near the edge of the ACC platform and lengthen or widen the platform are developed to effectively improving the thermal flow field, and enhanced the heat dispersal of ACC.

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What can idealized storm surge simulations tell us about worst case scenarios?

10.5194/egusphere-egu21-12284 ◽

2021 ◽

Author(s):

Elin Andrée ◽

Jian Su ◽

Martin Drews ◽

Morten Andreas Dahl Larsen ◽

Asger Bendix Hansen ◽

...

Keyword(s):

Wind Speed ◽

Sea Level ◽

North Sea ◽

Wind Direction ◽

Water Levels ◽

Sea Levels ◽

The North ◽

The North Sea ◽

Sea Coast ◽

North Sea Coast

The potential impacts of extreme sea level events are becoming more apparent to the public and policy makers alike. As the magnitude of these events are expected to increase due to climate change, and increased coastal urbanization results in ever increasing stakes in the coastal zones, the need for risk assessments is growing too.The physical conditions that generate extreme sea levels are highly dependent on site specific conditions, such as bathymetry, tidal regime, wind fetch and the shape of the coastline. For a low-lying country like Denmark, which consists of a peninsula and islands that partition off the semi-enclosed Baltic Sea from the North Sea, a better understanding of how the local sea level responds to wind forcing is urgently called for.We here present a map for Denmark that shows the most efficient wind directions for generating extreme sea levels, for a total of 70 locations distributed all over the country&#8217;s coastlines. The maps are produced by conducting simulations with a high resolution, 3D-ocean model, which is used for operational storm surge modelling at the Danish Meteorological Institute. We force the model with idealized wind fields that maintain a fixed wind speed and wind direction over the entire model domain. Simulations are conducted for one wind speed and one wind direction at a time, generating ensembles of a set of wind directions for a fixed wind speed, as well as a set of wind speeds for a fixed wind direction, respectively.For each wind direction, we find that the maximum water level at a given location increases linearly with the wind speed, and the slope values show clear spatial patterns, for example distinguishing the Danish southern North Sea coast from the central or northern North Sea Coast. The slope values are highest along the southwestern North Sea coast, where the passage of North Atlantic low pressure systems over the shallow North Sea, as well as the large tidal range, result in a much larger range of variability than in the more sheltered Inner Danish Waters. However, in our simulations the large fetch of the Baltic Sea, in combination with the funneling effect of the Danish Straits, result in almost as high water levels as along the North Sea coast.Although the wind forcing is completely synthetic with no spatial and temporal structure of a real storm, this idealized approach allows us to systematically investigate the sea level response at the boundaries of what is physically plausible. We evaluate the results from these simulations by comparison to peak water levels from a 58 year long, high resolution ocean hindcast, with promising agreement.

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Bayesian Model Averaging for Wind Speed Ensemble Forecasts Using Wind Speed and Direction

Weather and Forecasting ◽

10.1175/waf-d-17-0091.1 ◽

2017 ◽

Vol 32 (6) ◽

pp. 2217-2227 ◽

Cited By ~ 7

Author(s):

Siri Sofie Eide ◽

John Bjørnar Bremnes ◽

Ingelin Steinsland

Keyword(s):

Wind Speed ◽

Wind Direction ◽

Bayesian Model Averaging ◽

Weather Prediction ◽

Model Averaging ◽

Strong Wind ◽

Ensemble Forecasts ◽

Wind Speeds ◽

Low Wind Speeds ◽

The One

Abstract In this paper, probabilistic wind speed forecasts are constructed based on ensemble numerical weather prediction (NWP) forecasts for both wind speed and wind direction. Including other NWP variables in addition to the one subject to forecasting is common for statistical calibration of deterministic forecasts. However, this practice is rarely seen for ensemble forecasts, probably because of a lack of methods. A Bayesian modeling approach (BMA) is adopted, and a flexible model class based on splines is introduced for the mean model. The spline model allows both wind speed and wind direction to be included nonlinearly. The proposed methodology is tested for forecasting hourly maximum 10-min wind speeds based on ensemble forecasts from the European Centre for Medium-Range Weather Forecasts at 204 locations in Norway for lead times from +12 to +108 h. An improvement in the continuous ranked probability score is seen for approximately 85% of the locations using the proposed method compared to standard BMA based on only wind speed forecasts. For moderate-to-strong wind the improvement is substantial, while for low wind speeds there is generally less or no improvement. On average, the improvement is 5%. The proposed methodology can be extended to include more NWP variables in the calibration and can also be applied to other variables.

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Design of Small Wind Turbine

Volume 1: Symposia, Parts A and B ◽

10.1115/fedsm2008-55326 ◽

2008 ◽

Author(s):

R. S. Amano ◽

Ryan Malloy

Keyword(s):

Wind Speed ◽

Wind Turbine ◽

Wind Direction ◽

Pitch Angle ◽

Bridge Circuit ◽

Small Wind Turbine ◽

Swash Plate ◽

Wind Vane ◽

Blade Pitch Angle

The project has been completed, and all of the aforementioned objectives have been achieved. An anemometer has been constructed to measure wind speed, and a wind vane has been built to sense wind direction. An LCD module has been acquired and has been programmed to display the wind speed and its direction. An H-Bridge circuit was used to drive a gear motor that rotated the nacelle toward the windward direction. Finally, the blade pitch angle was controlled by a swash plate mechanism and servo motors installed on the generator itself. A microcontroller has been programmed to optimally control the servo motors and gear motor based on input from the wind vane and anemometer sensors.

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