scholarly journals Development of aerodynamic noise prediction technique for high efficiency and low noise design of unmanned aerial vehicle propeller

2017 ◽  
Vol 36 (2) ◽  
pp. 89-99
Author(s):  
Doo Young Gwak ◽  
Soogab Lee
Keyword(s):  
Unmanned Aerial Vehicle ◽  
High Efficiency ◽  
Low Noise ◽  
Aerodynamic Noise ◽  
Noise Prediction ◽  
Prediction Technique ◽  
Aerial Vehicle ◽  
Low Noise Design

scholarly journals Using Improved Edge Detection Method to Detect Mining-Induced Ground Fissures Identified by Unmanned Aerial Vehicle Remote Sensing

2021 ◽  
Vol 13 (18) ◽  
pp. 3652
Author(s):  
Duo Xu ◽  
Yixin Zhao ◽  
Yaodong Jiang ◽  
Cun Zhang ◽  
Bo Sun ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Edge Detection ◽  
Unmanned Aerial Vehicle ◽  
Field Experiments ◽  
High Efficiency ◽  
Detection Method ◽  
Laplacian Operator ◽  
Ground Fissures ◽  
Aerial Vehicle ◽  
Edge Detection Method

Information on the ground fissures induced by coal mining is important to the safety of coal mine production and the management of environment in the mining area. In order to identify these fissures timely and accurately, a new method was proposed in the present paper, which is based on an unmanned aerial vehicle (UAV) equipped with a visible light camera and an infrared camera. According to such equipment, edge detection technology was used to detect mining-induced ground fissures. Field experiments show high efficiency of the UAV in monitoring the mining-induced ground fissures. Furthermore, a reasonable time period between 3:00 a.m. and 5:00 a.m. under the studied conditions helps UAV infrared remote sensing identify fissures preferably. The Roberts operator, Sobel operator, Prewitt operator, Canny operator and Laplacian operator were tested to detect the fissures in the visible image, infrared image and fused image. An improved edge detection method was proposed which based on the Laplacian of Gaussian, Canny and mathematical morphology operators. The peak signal-to-noise rate, effective edge rate, Pratt’s figure of merit and F-measure indicated that the proposed method was superior to the other methods. In addition, the fissures in infrared images at different times can be accurately detected by the proposed method except at 7:00 a.m., 1:00 p.m. and 3:00 p.m.

Design of a Propeller Fan Using 3-D Inverse Design Method and CFD for High Efficiency and Low Aerodynamic Noise

2009 ◽  
Author(s):  
Hidenobu Okamoto ◽  
Akira Goto ◽  
Masato Furukawa
Keyword(s):  
High Efficiency ◽  
Design Method ◽  
Selective Laser Sintering ◽  
Design Guidelines ◽  
Low Noise ◽  
Inverse Design ◽  
Aerodynamic Noise ◽  
Pressure Jump ◽  
Blade Loading ◽  
Inverse Design Method

Three-Dimensional Inverse Design Method, where the 3-D blade profile is designed for a specified blade loading distribution, has been applied for designing a propeller fan rotor with high efficiency and low noise. A variety of the blade loading distributions (pressure jump across the blade), vortex pattern (forced vortex, free vortex, and compound vortex) and the stacking conditions (sweep angles) were specified and the corresponding 3-D blade configurations were obtained. Among the 22 different designs, 14 propeller fan rotors including the reproduced baseline fan were manufactured by a rapid prototyping based on a selective laser sintering system (SLS) and tested. It was confirmed experimentally that the best design achieved about 5.7 points improvement in the peak total-to-static efficiency and the 2.6dB(A) reduction in aerodynamic noise. The flow mechanisms leading to the higher efficiency and lower aerodynamic noise were discussed based on experiments and the RANS steady flow simulations. Based on these investigations, design guidelines for the inverse design of propeller fan rotors with higher efficiency and lower aerodynamic noise were proposed.

Application of Unmanned Aerial Vehicle Remote Sensing for Geological Disaster Reconnaissance along Transportation Lines: A Case Study

2012 ◽  
Vol 226-228 ◽  
pp. 2376-2379 ◽  
Author(s):  
Ji Ping Hu ◽  
Wen Bin Wu ◽  
Qu Lin Tan
Keyword(s):  
Remote Sensing ◽  
Unmanned Aerial Vehicle ◽  
High Efficiency ◽  
Scientific Data ◽  
Geological Investigation ◽  
Geological Disaster ◽  
Transportation Line ◽  
Aerial Vehicle ◽  
Engineering Geological Investigation

Compared with conventional airborne remote sensing application to engineering geological investigation, High precision Unmanned Aerial Vehicle Remote Sensing (UAV-RS) technology can improve work condition with advantages of high flexibility, low cost, high efficiency and up-to-date situation acquisition. Especially, it has very important engineering significance for quick and urgent geological disaster reconnaissance along transportation lines. In the paper, some aspects of application to transportation-line (pipeline, highway and railway) engineering geological investigation were discussed. The concerned key points, including components of UAV-RS system, data processing workflow and image interpretation were analyzed. As a case study, a UAV-RS application project for transportation-line geological disaster investigation was given. The utilization of this new remote sensing technology successfully collected and discovered potential geological disasters and provided scientific data for timely decision-making.

A research into the potential application of unmanned aerial vehicles in the fire extinguishing of high-rise buildings and structures

2021 ◽  
Vol 30 (3) ◽  
pp. 54-64
Author(s):  
S. G. Tsarichenko ◽  
A. V. Ostrovoy ◽  
S. V. Karasev ◽  
M. L. Pugachev
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Unmanned Aerial Vehicle ◽  
High Efficiency ◽  
Water Mist ◽  
Economic Feasibility ◽  
Safety Testing ◽  
High Rise ◽  
Fire Extinguishing ◽  
Aerial Vehicles ◽  
Aerial Vehicle

Introduction. Fires in high-rise buildings and structures constitute a grave danger both to the people inside, valuables, and the building structure. More often than not, fires develop on the external surface of construction facilities that are in operation or inside those facilities that are under construction, and they give rise to the problem of using standard fire extinguishing solutions and require the employment of mobile machinery by fast response units of the fire-fighting service who apply fire extinguishing agents from the outside of a building. The purpose of this article is to substantiate the in expediency of, or, on the contrary, the need to make the proposed amendments to Federal Law No. 123-FZ of July 22, 2008 “Technical Regulation of Fire Safety Requirements”.The scope of the problem. The analysis of the effectiveness of various methods of application of fire extinguishing agents used to extinguish outdoor fires in high-rise buildings has shown the insufficiently high efficiency of ground-mounted machinery, which preconditions the need to make an enquiry into the possibility of using aircraft to extinguish high-rise buildings and structures. Given the need to ensure effective fire extinguishing, meet safety and economic feasibility requirements, an autonomous unmanned aerial vehicle (AURA) was selected as the delivery vehicle. Systems using various fire extinguishing agents and methods of their application were used for fire extinguishing purposes, including a pulsed water application system, capsules containing the fire extinguishing composition, high-pressure water mist and compressed air foam. Their applicability at the height of 300 meters has determined their choice.Research results. The testing task was to confirm the possibility of application of fire extinguishing agents to the fire seat in the course of the flight of an unmanned aerial vehicle, to identify the effectiveness of fire extinguishing agents and to assess the stability of extinguishing agents applied to the fire seat. To ensure safety, testing was carried out at the height not exceeding 10 m, and the results confirmed the possibility of using the above substances to extinguish fires.Conclusions. The research has confirmed the possibility of using unmanned aerial vehicles and various methods of fire extinguishing by means of the horizontal application of extinguishing agents inside high-rise buildings and structures, if extinguishing agents are applied from outside of a construction facility.

Study on Overall Design of a Vertical Take-Off and Landing Unmanned Aerial Vehicle Powered by Electric Ducted Fans

2021 ◽  
Author(s):  
Tawei Chou ◽  
Qiyu Ying ◽  
Yuping Qian ◽  
Weilin Zhuge ◽  
Yangjun Zhang
Keyword(s):  
Power Unit ◽  
Unmanned Aerial Vehicle ◽  
Cfd Simulation ◽  
Design Method ◽  
Load Capacity ◽  
Design Procedure ◽  
Low Noise ◽  
Overall Design ◽  
Ducted Fan ◽  
Aerial Vehicle

Abstract Facing the growing traffic fleet in the cities nowadays, it is believed that three-dimensional urban transportation could be a solution and will be introduced in the near future. Vertical take-off and landing flying platforms powered by ducted fans will attract increasingly attention because it has advantages on high propulsion efficiency, low noise, and better safety. However, unlike traditional open-blade multi-rotor drones, ducted fan drones lack a systematic design approach that comprehensively considers the overall system performance and the power unit efficiency. Current design procedure leads to insufficient load capacity and low efficiency systems. This paper proposes an overall design method for a ducted fan-type vertical take-off and landing flight platform. The ducted fan and motor of the core power unit are designed and selected aiming at improving aerodynamic efficiency and structural utilization of the system. A heavy-load vertical take-off and landing Unmanned Aerial Vehicle (UAV) powered by ducted fans with a take-off weight of 450kg is designed based on this method. CFD simulation is utilized to calculate the performance of the designed Unmanned Aerial Vehicle, and finite element analysis is carried out to examine the overall strength safety. The final design results show that the overall design method plays a great role in the development of ducted fan UAV.

Application of Synchronous Rectifiers in Power Supply for Unmanned Aerial Vehicle

2011 ◽  
Vol 130-134 ◽  
pp. 154-157
Author(s):  
He Na Chen ◽  
Yi Ming Zhang ◽  
Hai Juan Wang
Keyword(s):  
Unmanned Aerial Vehicle ◽  
Power Supply ◽  
High Efficiency ◽  
Low Voltage ◽  
Charge Retention ◽  
Current Output ◽  
Forward Converter ◽  
Switching Power ◽  
Aerial Vehicle ◽  
Gate Charge

Power supply for Unmanned Aerial Vehicle (UAV) low voltage, high current output, so conventional diode rectifier circuit had been unable to meet the high efficiency in switching power supply, which should selected synchronous rectification (SR). But conventional gate charge retention drive existed dead time and constant drive voltage problems. In this paper, proposes a new gate charge retention drive to improve the phenomenon. Using Saber to analysis the two methods, we could verify the accuracy of the theory. Finally, 72v input 6v/20 output forward converter are designed using the new methods and 90% efficiency is achieved at full load.

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