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Path Planning of the Low Altitude Flight Unmanned Aerial Vehicle for the Neutralization of the Enemy Firepower (대화력전 임무수행을 위한 저고도 비행 무인공격기의 경로계획)

  • Yang, Kwang-Jin;Kim, Si-Tai;Jung, Dae-Han
    • Journal of the Korea Institute of Military Science and Technology
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    • v.15 no.4
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    • pp.424-434
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    • 2012
  • This paper presents a path planning algorithm of the unmanned aerial vehicle for the neutralization of the enemy firepower. The long range firepower of the ememy is usually located at the rear side of the mountain which is difficult to bomb. The path planner not only consider the differential constraints of the Unmanned Aerial Vehicle (UAV) but also consider the final approaching angle constraint. This problem is easily solved by incorporating the analytical upper bounded continuous curvature path smoothing algorithm into the Rapidly Exploring Random Tree (RRT) planner. The proposed algorithm can build a feasible path satisfying the kinematic constraints of the UAV on the fly. In addition, the curvatures of the path are continuous over the whole path. Simulation results show that the proposed algorithm can generate a feasible path of the UAV for the bombing mission regardless of the posture of the tunnel.

Overview on High Speed Rotorcraft Concepts for the Personal Aerial Vehicle(PAV) Applications (PAY 적용을 위한 고속 회전익기 개념 개괄)

  • Hawang, Chang-Jeon;Ahn, Byung-Ho
    • Aerospace Engineering and Technology
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    • v.6 no.1
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    • pp.6-13
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    • 2007
  • PAV(Personal Air Vehicle) can be an alternative of the saturated ground transportation in future and can be available in any time and anywhere. This paper describes some overview on high speed rotorcraft concepts for the PAV applications. First the requirement of PAV is surveyed. Then the existing concepts of high speed rotorcrafts are reviewed. Several on-going projects are summarized. Finally! technical issues of high speed rotorcraft to apply to PAV platform are explored.

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A Study on Prediction Method of Vehicle Cooling Performance with A/C Condenser (A/C 콘덴서를 포함한 차량냉각 성능예측에 관한 연구)

  • 이상호;박정원
    • Transactions of the Korean Society of Automotive Engineers
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    • v.10 no.3
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    • pp.51-60
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    • 2002
  • An analysis method to predict performance of a vehicle cooling system which is composed of radiator, A/C condenser, cooling fan, and etc. is suggested. Air flow through the heat exchanger system and heat rejection rate which dominate the cooling performance are analyzed. Heat transfer with A/C refrigerant phase change is also considered in the analysis. Some predicted results are compared with experimental data for various operating conditions. This evaluation procedure will be useful for the design of optimal vehicle cooling system.

Potential Exposure to RSP, $NO_2$ and VOCs for Taxi Professional Driver

  • Kim, Dae-Won;Lee, Jung-Eun;Son, Bu-Soon;Kim, Young-Hee;Yang, Won-Ho
    • Proceedings of the Korean Environmental Health Society Conference
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    • 2005.06a
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    • pp.299-302
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    • 2005
  • Vehicle occupant exposure to air pollutants has been a subject of concern in recent years because of higher levels of air pollutants inside gasoline or diesel-using vehicle, comparing to the surrounding atmosphere. This study evaluated the potential exposure to respirable suspended particulate (RSP), nitrogen dioxide ($NO_2$) and volatile organic compounds (VOCs), comparing weekday (Monday and Thursday) and weekend (Saturday). Indoor mean concentrations of RSP inside vehicle were 51.2 $ug/m^3$ and 75.52 $ug/m^3$ in weekday and weekend, respectively. Measured indoor NO$_2$ concentrations were 14,8 ppb and 20.8 ppb, respectively. Benzene and toluene mean concentrations inside vehicle were 5.4${\pm}$2.4 ppb and 23.8${\pm}$33.8 ppb, respectively.

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Estimation of Emission Factor and Air Pollutant Emissions by Motor Vehicles (自動車에 의한 汚染物質 排出係數 및 排出量 算定에 관한 硏究)

  • 趙康來;金良均;董宗仁;嚴明道
    • Journal of Korean Society for Atmospheric Environment
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    • v.3 no.1
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    • pp.55-64
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    • 1987
  • Actual driving pattern of each motor vehicle type was measured and analyzed in Seoul area and vehicle emission rate was measured and traffic data were used to estimate vehicular emission factor and motor vehicle-related air pollutant emission. The analysis of contribution ratio of each vehicle type showed that LPG taxi's took 38.1% of total vehicular CO, gasoline passenger cars 37.5%, therefore, these cars are major sources of CO, gasoline passenger cars took 45.4% of total vehicular HC, motorcycles 25.3%, LPG taxi's 16.2%, so motorcycles can be said to play an important role in HC emission. For NOx, buses and trucks were thought to be major sources as buses took 36.8% and truck 26.4%. Diesel vehicles, on the other hand, took most $SO_2$ and particulate matter emission. Total emission from motor vehicles in Seoul was estimated to be 547 t/day of CO, 68t/day of HC, 163t/day of NOx, 18t/day of $SO_2$ and 19t/day of paticulate matter.

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A Study on the Heat Load Transferred to a Passenger Vehicle (자동차 열부하의 계산)

  • 오상한;이창원;원성필
    • Transactions of the Korean Society of Automotive Engineers
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    • v.4 no.2
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    • pp.50-59
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    • 1996
  • The computer simulation program that calculates the transient heat load transferred to a passenger vehicle has been developed. Method for modeling mathematically various kinds of the heat load was presented and the derived equations were solved numerically. To find out the accuracy of the simulation program, the correlation of experimental and analytical results was demonstrated. By using this program, the typical characteristics about temperature distribution and instantaneous or of vehicle body color, material of glass, air-conditioning capacity, driving direction, and speed. Under a steady-state condition, the ratios of the heat load, resulting form vehicle body, glass, and interior part, were 35%, 29%, and 36%, respectively.

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Improvement of Flapping Air Vehicle by Using Axiomatic Design (공리적 설계를 이용한 Flapping 비행체의 성능 개선)

  • 성호석;차성운;이경수
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1997.10a
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    • pp.684-688
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    • 1997
  • The human species has been able to fly for about a century - with the help of aircraft of various kinds. Recently. air vehicles which are like an insect or a bird with flapping wings have been appeared, although many of them are experimental flight vehicle. However, the rubber-powered flapping vehicle is put to practical use such as toy, which flies for some seconds. In this paper, we analyze and evaluate above the rubber-powered flight vehicle using axiomatic design and will present new four flapping wing model.

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Experimental Study on the Heating Performances of the Air Heater with Diesel for Passenger Cabin Heating of an Electric Vehicle (전기자동차용 승차공간 난방용 디젤 공기 히터의 실차 성능에 관한 연구)

  • Bang, You-Ma;Seo, Jae-Hyeong;Lee, Moo-Yeon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.11
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    • pp.7250-7255
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    • 2015
  • The objective of this study is to experimentally investigate the heating performances of the portable air combustion heater using diesel fuel for auxiliary cabin heating of the battery electric vehicle. In order to evaluate the heating performances of the air combustion heater, the heating capacity was calculated by the temperature at inlet and outlet parts of the considered heater and the inner temperature distribution characteristics of the vehicle were measured during 1600 seconds with an interval of 1 second. The theoretical efficiency of the tested heater was calculated by temperature data of the air of supplying and exhausting to the cabin. As the air passed the heat-sink, the air temperature at the end of heat-sink reached to $101.3^{\circ}C$ and the difference of temperature on heat-sink was 67.8%. The average heating capacity of the air combustion heater showed 2.0 kW. After 1800 seconds, the inner temperature of the vehicle cabin was continuously increased. The temperatures of the top side and the bottom side of the car cabin under consideration were increased upto $42.5^{\circ}C$ and $24.3^{\circ}C$, respectively, and the theoretical efficiency of the tested heater was on average 63.7%.

Analysis and Alternative Circuit Design of Pneumatic Circuit for An Automotive Air Suspension (자동차 공기현가 공압회로 해석 및 대체회로 설계)

  • Lee, J.C.
    • Transactions of The Korea Fluid Power Systems Society
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    • v.5 no.4
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    • pp.17-25
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    • 2008
  • This study presents an analytical model of the pneumatic circuit of an air suspension system to analyze the characteristics of vehicle height control. The analytical model was developed through the co-simulation of Simulink(air spring) and HyPneu(pneumatic circuit). Variant effective area of air spring and flow coefficients of pneumatic valves were estimated experimentally prior to the system test, and utilized in simulation. One-comer test apparatus was established using the components of commercial air suspension products. The results of simulation and experiment were so close that the proposed analytical model in this study was validated. However the frictional loss of conduit and heat dissipation which were ignored in this study need to be considered in future study. As an application example of proposed analytical model, an alternative pneumatic circuit of air suspension to conventional WABCO circuit was evaluated. The comparison of simulation results of WABCO circuit and alternative circuit show that proposed analytical model of co-simulation in this study is useful for the study of pneumatic system of automotive air suspension.

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A Case Study of Decreasing Environment Pollution Caused by Energy Consumption of a Dormitory Building Which Only Using Electricity by Efficiently Simulating Applying Residential SOFC (Solid Oxide Fuel Cell)

  • Chang, Han;Lee, In-Hee
    • Architectural research
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    • v.21 no.1
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    • pp.21-29
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    • 2019
  • Recent years in Korea, some new developed buildings are only using electricity as power for heating, cooling, bathing and even cooking which means except electricity, there is no natural gas or other kinds of energy used in such kind of building. In vehicle industry area, scientists already invented electric vehicle as an environment friendly vehicle; after that, in architecture design and construction field, buildings only using electricity appeared; the curiosity of the environment impact of energy consumption by such kind of building lead me to do this research. In general, electricity is known as a clean energy resource reasoned by it is noncombustible energy resource; however, although there is no environmental pollution by using electricity, electricity generation procedure in power plant may cause huge amount of environment pollution; especially, electricity generation from combusting coal in power plant could emit enormous air pollutants to the air. In this research, the yearly amount of air pollution by energy using under traditional way in research target building that is using natural gas for heating, bathing and cooking and electricity for lighting, equipment and cooling is compared with yearly amount of air pollution by only using electricity as power in the building; result shows that building that only uses electricity emits much more air pollutants than uses electricity and natural gas together in the building. According to the amount of air pollutants comparison result between two different energy application types in the building, residential SOFC (Solid oxide fuel cell) is simulated to apply in this building for decreasing environment pollution of the building; furthermore, high load factor could lead high efficiency of SOFC, in the scenario of simulating applying SOFC in the building, SOFC is shared by two or three households in spring and autumn to increase efficiency of the SOFC. In sum, this research is trying to demonstrate electricity is a conditioned environment friendly energy resource; in the meanwhile, SOFC is simulated efficiently applying in the building only using electricity as power to decrease the large amount of air pollutants by energy using in the building. Energy consumption of the building is analyzed by calibrated commercial software Design Builder; the calibrated mathematical model of SOFC is referred from other researcher's study.