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Development of On-line Performance Diagnostic Program of a Helicopter Turboshaft Engine
Changduk Kong,Youngju Koo,Seonghee Kho,Hyeok Ryu 한국항공우주학회 2009 International Journal of Aeronautical and Space Sc Vol.10 No.2
Gas turbine performance diagnostics is a method for detecting, isolating and quantifying faults in gas turbine gas path components. On-line precise fault diagnosis can promote greatly reliability and availability of gas turbine in real time operation. This work proposes a GUI-type on-line diagnostic program using SIMULINK and Fuzzy-Neuro algorithms for a helicopter turboshaft engine. During development of the diagnostic program, a look-up table type base performance module are used for reducing computer calculating time and a signal generation module for simulating real time performance data. This program is composed of the on-line condition monitoring program to monitor on-line measuring performance condition, the fuzzy inference system to isolate the faults from measuring data and the neural network to quantify the isolated faults. Evaluation of the proposed on-line diagnostic program is performed through application to the helicopter engine health monitoring.
Performance Simulation of a Turboprop Engine for Basic Trainer
Kong, Changduk,Ki, Jayoung,Chung, Sukchoo The Korean Society of Mechanical Engineers 2002 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.16 No.6
A performance simulation program for the turboprop engine (PT6A-62), which is the power plant of the first Korean indigenous basic trainer KT-1, was developed for performance prediction, development of an EHMS (Engine Health Monitoring System) and the flight simulator. Characteristics of components including compressors, turbines, power turbines and the constant speed propeller were required for the steady state and transient performance analysis with on and off design point analysis. In most cases, these were substituted for what scaled from similar engine components'characteristics with the scaling law. The developed program was evaluated with the performance data provided by the engine manufacturer and with analysis results of GASTURB program, which is well known for the performance simulation of gas turbines. Performance parameters such as mass flow rate, compressor pressure ratio, fuel flow rate, specific fuel consumption and turbine inlet temperature were discussed to evaluate validity of the developed program at various cases. The first case was the sea level static standard condition and other cases were considered with various altitudes, flight velocities and part loads with the range between idle and 105% rotational speed of the gas generator. In the transient analysis, the Continuity of Mass Flow Method was utilized under the condition that mass stored between components is ignored and the flow compatibility is satisfied, and the Modified Euler Method was used for integration of the surplus torque. The transient performance analysis for various fuel schedules was performed. When the fuel step increase was considered, the overshoot of the turbine inlet temperature occurred. However, in case of ramp increase of the fuel longer than step increase of the fuel, the overshoot of the turbine inlet temperature was effectively reduced.
Changduk Kong 한국항공우주학회 2014 International Journal of Aeronautical and Space Sc Vol.15 No.2
The aviation gas turbine is composed of many expensive and highly precise parts and operated in high pressure and temperature gas. When breakdown or performance deterioration occurs due to the hostile environment and component degradation, it severely influences the aircraft operation. Recently to minimize this problem the third generation of predictive maintenance known as condition based maintenance has been developed. This method not only monitors the engine condition and diagnoses the engine faults but also gives proper maintenance advice. Therefore it can maximize the availability and minimize the maintenance cost. The advanced gas turbine health monitoring method is classified into model based diagnosis (such as observers, parity equations, parameter estimation and Gas Path Analysis (GPA)) and soft computing diagnosis (such as expert system, fuzzy logic, Neural Networks (NNs) and Genetic Algorithms (GA)). The overview shows an introduction, advantages, and disadvantages of each advanced engine health monitoring method. In addition, some practical gas turbine health monitoring application examples using the GPA methods and the artificial intelligent methods including fuzzy logic, NNs and GA developed by the author are presented.
Kong, Changduk,Kim, Kibeom CHOSUN UNIVERSITY 1997 Basic Science and Engineering Vol.1 No.1
In this study, there were performed some processes concerning to basic structural design, stress analysis, and structural testing in order to design the aircraft composite propeller blade. At first, calculating the structural stress on a simplified load condition performed to the basic design. At second, the variable static and dynamic load condition was applied for the structural analysis of blade by using finite element method. Finally, the structural experiment of blade was performed to get some data about the stability and strength of blade structures. Also, the compatibility of finite element model was verified. The static load testing, the bird strike testing, and the natural vibration testing were performed for the structural experiments. A Carbon/Epoxy composite was used to the material of the blade. And for manufacturing, there was inducted RTM(Resin Transfer Molding) process. As the result of this study, there was confirmed in the adequate structural strength, also the analytical and experimental design procedure was established.
Changduk Kong,Hyunbum Park,Sanghoon Kim 한국항공우주학회 2008 한국항공우주학회 학술발표회 논문집 Vol.- No.-
This study aims to investigate the residual strength of sandwich composites structure with aluminum honeycomb core and glass/epoxy face sheets subjected to the impact damage and quasi-static indentation damage by the experimental. The edge-wise compressive strength test was used to find the mechanical properties according to the ASTM standard test procedure. The damaged specimens by low velocity impact and quasi static indentation were finally assessed by this test procedure. The investigation results revealed the residual strength comparison of damaged specimens due to impact loading and quasi static indented specimens.