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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of the Korean Society for Aeronautical & Space Sciences
Journal Basic Information
Journal DOI :
The Korean Society for Aeronautical & Space Sciences
Editor in Chief :
Volume & Issues
Volume 39, Issue 12 - Dec 2011
Volume 39, Issue 11 - Nov 2011
Volume 39, Issue 10 - Oct 2011
Volume 39, Issue 9 - Sep 2011
Volume 39, Issue 8 - Aug 2011
Volume 39, Issue 7 - Jul 2011
Volume 39, Issue 6 - Jun 2011
Volume 39, Issue 5 - May 2011
Volume 39, Issue 4 - Apr 2011
Volume 39, Issue 3 - Mar 2011
Volume 39, Issue 2 - Feb 2011
Volume 39, Issue 1 - Jan 2011
Selecting the target year
A Study on Truncated Flapped Airfoil for Efficient Icing Wind Tunnel Test
Jung, Sung-Ki ; Lee, Chang-Hoon ; Nagdewe, Suryakant ; Myong, Rho-Shin ; Cho, Tae-Hwan ;
Journal of the Korean Society for Aeronautical & Space Sciences, volume 39, issue 6, 2011, Pages 481~486
DOI : 10.5139/JKSAS.2011.39.6.481
The evaluation of supercooled water droplet impingement characteristics of full-scale aircraft components in wind tunnels under icing conditions has been severely limited by the relative size of the component and the test facility. The concept of truncated airfoil sections has been suggested in order to extend the operational range of icing tunnels. With proper deflection of the small trailing-edge flap on the truncated airfoil the local pressure distribution may remain very close to that of the full-scale airfoil. In this study the shape of a truncated flapped airfoil is investigated for various deflection angles. To validate the truncated flapped airfoils, air flow and collection efficiency over the truncated airfoil are compared with the results of the full-scale airfoil obtained from the state-of-the-art icing simulation code.
Trim Range and Characteristics of Autorotation(I): Rotor Speed Limit and Pitch Range
Kim, Hak-Yoon ; Choi, Seong-Wook ;
Journal of the Korean Society for Aeronautical & Space Sciences, volume 39, issue 6, 2011, Pages 487~497
DOI : 10.5139/JKSAS.2011.39.6.487
Numerical analysis has been performed to investigate the rotor speed and pitch range variations when the airspeed is increased in autorotation. Transient Simulation Method(TSM) was used to obtain the steady states of autorotation. The rotor blade was analyzed by the two-dimensional compressible Navier-Stokes solver in order to adapt to the airspeed increase and the results were used in the transient simulation method. Meanwhile, the Pitt/Peters inflow theory was used to supply the induced velocity fields. For the prescribed torque equilibrium state, the combinations of velocity, shaft angle, and pitch angle were produced to investigate the rotor speeds and variable ranges. The rotor tip Mach number and rotor speed were correlated and the trim range of pitch angle was observed with respect to the shaft angle decrease.
Trim Range and Characteristics of Autorotation(II): Advance Ratio Variation and Flapping Characteristics
Kim, Hak-Yoon ; Choi, Seong-Wook ;
Journal of the Korean Society for Aeronautical & Space Sciences, volume 39, issue 6, 2011, Pages 498~504
DOI : 10.5139/JKSAS.2011.39.6.498
The flapping characteristics and advance ratios at torque equilibrium state of autorotation were investigated when the airspeed, shaft angle, and pitch angle were varied. To simulate the airspeed increase, the aerodynamic data analyzed by using the compressible Navier-Stokes solver and Pitt/Peters inflow theory were used. Transient Simulation Method(TSM) was used to catch the torque equilibrium states. The maximum flapping angles at torque equilibrium state were correlated to the airspeed, shaft angle, and pitch angle. By comparing flapping behavior to the variation of advance ratio, the phenomenon that the extension of reverse flow area of retreating blade affects the characteristics of autorotation was qualitatively considered.
Integrated Guidance and Control Law with Impact Angle Constraint
Yun, Joong-Sup ; Park, Woo-Sung ; Ryoo, Chang-Kyung ;
Journal of the Korean Society for Aeronautical & Space Sciences, volume 39, issue 6, 2011, Pages 505~516
DOI : 10.5139/JKSAS.2011.39.6.505
The concept of the IGC(Integrated Guidance and Control) has been introduced to overcome the performance limit of the SGC(Separated Guidance and Control) loop. A new type of IGC with impact angle constraint has been proposed in this paper. Angle of attack, pitch angle rate, pitch angle and line of sight angle are considered as state variables. A controllability analysis and equilibrium point analysis have been carried out to investigate the control characteristic of the prposed IGC. The LQR(Linear Quadratic Regulator) has been adopted for the control law and detailed explanations about the adoption has been provided. The performance comparison between the IGC and the SGC has been carried out. The result of numerical simulations shows that the IGC guarantees better guidance performance than the SGC when the agile maneuver is needed for a specific guidance geometry.
Electromechanical Modeling and Experimental Verification of Differential Vibrating Accelerometer
Lee, Jung-Shin ; Rhim, Jae-Wook ;
Journal of the Korean Society for Aeronautical & Space Sciences, volume 39, issue 6, 2011, Pages 517~525
DOI : 10.5139/JKSAS.2011.39.6.517
Differential Vibrating Accelerometer(DVA) is a small and accurate resonant device to sense the change in natural frequency in presence of acceleration input. Both mathematical modeling for the electromechanical dynamics and experimental investigation on the structural characteristics are necessary for effective designs of precision controller and high Q-factor structure. In this paper, electromechanical modeling of the resonator of DVA, electrode module, and pre-amplifier is presented. The presented method is experimentally verified by measuring the resonance frequency, effective mass, effective stiffness and Q-factor. The direct comparison of the calculated displacement and the actual pre-amplifier of DVA also indicates the effectiveness of this study.
Conceptual Design of Multi-Functional Structure using Rectangular Grid-Stiffened Structure for Satellite
Seo, Hyun-Suk ; Jang, Tae-Seong ; Rhee, Ju-Hun ; Kim, Won-Seock ; Hyun, Bum-Seok ; Lim, Jae-Hyuk ; Hwang, Do-Soon ; Lee, Sang-Kon ; Cho, Hee-Keun ; Han, Eun-Soo ; Kim, Im-Soo ; Sim, Eun-Sup ;
Journal of the Korean Society for Aeronautical & Space Sciences, volume 39, issue 6, 2011, Pages 526~534
DOI : 10.5139/JKSAS.2011.39.6.526
The MFS (Mlti-Functional Structure) concept, which integrates the electronics, thermal control and structure into a single packaging system, has been developed and applied to reduce the volume and weight of the satellite. Therefore, this MFS can eliminate the bulky chassis/frames, cables and connectors of the electronic equipment. The main point of this traditional MFS is the replacement of the electrical chassis/frames with MCMs (Multi-Chip Modules) that require much costs and efforts for developing. This paper shows the new MFS concept that effectively saves the volume and weight. The structure including the thermal control and radiation shielding elements will be designed and manufactured as the rectangular grid-stiffened structure. The rectangular grid-stiffened structure is the modification of the iso-grid structure, and provides the enough spaces for putting the general PCBs without the chassis/frames.
Obstacle Avoidance of GNSS Based AGVs Using Avoidance Vector
Kang, Woo-Yong ; Lee, Eun-Sung ; Chun, Se-Bum ; Heo, Moon-Beom ; Nam, Gi-Wook ;
Journal of the Korean Society for Aeronautical & Space Sciences, volume 39, issue 6, 2011, Pages 535~542
DOI : 10.5139/JKSAS.2011.39.6.535
The Global Navigation Satellite System(GNSS) is being utilized in numerous applications. The research for autonomous guided vehicles(AGVs) using precise positioning of GNSS is in progress. GNSS based AGVs is useful for setting driving path. This AGV system is more efficient than the previous one. Escipecially, the obstacle is positioned the driving path. Previcious AGVs which follow marker or wires laid out on the road have to stop the front of obstacle. But GNSS based AGVS can continuously drive using obstacle avoidance. In this paper, we developed collision avoidance system for GNSS based AGV using laser scanner and collision avoidance path setting algorithm. And we analyzed the developed system.
Low Cost Small CMG Performance Test and Analysis
Rhee, Seung-Wu ; Kwon, Hyoek-Jin ;
Journal of the Korean Society for Aeronautical & Space Sciences, volume 39, issue 6, 2011, Pages 543~552
DOI : 10.5139/JKSAS.2011.39.6.543
Control Moment Gyro(CMG) is one of the most efficient momentum exchange devices for satellite attitude control and CMG is very essential device for agile satellite. In this study, the essential dynamic equation for the design of gimbal motor and wheel motor is summarized. The development process of SGCMG hardware for agile small satellite system, the description of developed hardware and its performance test results are presented. Test result shows that the developed hardware model can produce an output torque more than 1.2Nm as designed. Other test items are max. torque, gimbal bandwidth, minimum torque, torque error, gimbal rate error.
Design, Implementation and Test of Flight Model of S-Band Transmitter for STSAT-3
Oh, Seung-Han ; Seo, Gyu-Jae ; Lee, Jung-Soo ; Oh, Chi-Wook ; Park, Hong-Young ;
Journal of the Korean Society for Aeronautical & Space Sciences, volume 39, issue 6, 2011, Pages 553~558
DOI : 10.5139/JKSAS.2011.39.6.553
This paper describes the development and test result of S-band Transmitter flight model(FM) of STSAT-3 by satellite research center(SaTReC), KAIST. The communication sub-system of STSAT-3 is consist of two different frequency band channels, S-band for Telemetry & Command and X-band for mission data. S-band Transmitter(STX) functionally made of modulator, frequency synthesizer, power amp and DC/DC converter. The transmission data is modulated by FSK(Frequency Shift Keying) and the interface between spacecraft sub-module and STX is RS-422 standard method. The FM STX is based on modular design. The RF output power of STX is 1.5W(31.7dBm) and BER of STX is under
which meets the specification respectively. The FM STX is delivered Spacecraft Assembly, Integration and Test(AIT) level through the completion of functional Test and environmental(vibration, thermal vacuum) Test successfully.
A Flow Channel Design on IR Window Cooling Device
Park, Youn-Jung ;
Journal of the Korean Society for Aeronautical & Space Sciences, volume 39, issue 6, 2011, Pages 559~566
DOI : 10.5139/JKSAS.2011.39.6.559
This paper presents the flow passage design for a window cooling device, which have a conical poppet valve and an emissive orifice. Computational flow analysis and experiment are conducted according to the poppet strokes. The results show satisfactory flow characteristics that pressure is reduced enough to endure material strength and the flow does not choked inside window. The correction factor of discharge coefficients is found between 2-dimensional analysis and experiments, which is applied to control coolant flow rates of the window cooling device.
Estimation of Production and Operation Cost of KSLV-II using TRANSCOST
Yoo, Dong-Seo ; Kim, Hong-Rae ; Choi, Jong-Kwon ; Chang, Young-Keun ;
Journal of the Korean Society for Aeronautical & Space Sciences, volume 39, issue 6, 2011, Pages 567~575
DOI : 10.5139/JKSAS.2011.39.6.567
The development of space launch vehicle is an important step to advance to developed countries in the space area. It is also so risky due to necessity of huge costs and longer development period. The accuracy of cost estimation is important to develop a space launch vehicle successfully and efficiently. It is also necessary to estimate production and operation cost in order to develop commercial space launch vehicle possessing competitiveness. In this paper, Korean factors to be able to reflect the current state of workforce, average working hours and technology readiness level in Korea were analyzed to estimate production and operation cost of space launch vehicles that are developed in Korea. Korean factors have been applied to production and operation cost estimation of KSLV-II based on TRANSCOST. We evaluated the competitiveness level of KSLV-II as the commercial launch vehicle in the commercial launch services market by comparing with cost per flight of foreign launch vehicles.
Cost Model for Annual Cost Spread Estimation of Space Launch Vehicle Development
Kim, Hong-Rae ; Yoo, Dong-Seo ; Choi, Jong-Kwon ; Chang, Young-Keun ;
Journal of the Korean Society for Aeronautical & Space Sciences, volume 39, issue 6, 2011, Pages 576~584
DOI : 10.5139/JKSAS.2011.39.6.576
In order to develop a launch vehicle successfully, it is important to estimate development costs accurately but it is also important to plan the annual budget. In this paper, the statistical method was utilized for cost spreading. For cost spread modeling, the suitability of the model by analyzing several statistical models was evaluated and consequently, the beta-distribution model has been selected. In this study, the validity of the annual estimation cost model was verified through the comparison of the actual development cost distribution and the estimating cost distribution of Space Shuttle Main Engine. In addition, this paper estimated the annual budget required for the development of the KSLV-II using currently allocated cost for successful development. It is anticipated that the present cost spread model can be applied to not only launch vehicle development but also other large complex system development.