• Journal of the Korean Society of Propulsion Engineers
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• v.10 no.2
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• pp.15-22
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• 2006

An intelligent performance diagnostic program using the Neural Network was proposed for PW206C turboshaft engine. It was selected as a power plant for the tilt rotor type Smart UAV(Unmanned Aerial Vehicle) which is being developed by KARI (Korea Aerospace Research Institute). For teeming the NN(Neural Network), a BPN(Back Propagation Network) with one hidden, one input and one output layer was used. The input layer has seven neurons: variations of measurement parameters such as SHP, MF, P2, T2, P4, T4 and T5, and the output layer uses 6 neurons: degradation ratios of flow capacities and efficiencies for compressor, compressor turbine and power turbine, respectively, Database for network teaming and test was constructed using a gas turbine performance simulation program. From application of the learned networks to diagnostics of the PW206C turboshaft engine, it was confirmed that the proposed diagnostics algorithm could detect well the single fault types such as compressor fouling and compressor turbine erosion.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.5
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• pp.586-592
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• 2014

This study looks at the design of a 100 kW blade geometry for a horizontal marine current turbine using the Blade Element Momentum Theory (BEMT) and by using (CFD), the power output, performance and characteristics of the the fluid flow over the blade is estimated. Three basic airfoils; FFA-W3-301, DU-93-W210 and NACA-63418, are used along the blade span and The distribution of the chord length and twist angles along the blade are obtained from the hydrodynamic optimization procedure. The power coefficient curve shows maximum peak at the rated tip speed ratio of 5.17, and the maximum power reaches about 101.82 kW at the power coefficient of 0.495.

• Journal of the Korean Society for Nondestructive Testing
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• v.24 no.4
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• pp.371-377
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• 2004

As the turbine running duration in nuclear power plants increases, cracks have been found in the pin finger type blade root area. The nondestructive examination for the blade root area has been carried out by manual ultrasonic examination during the overhaul period, but because of necessity to improve the reliability, we developed an automatic ultrasonic examination system and technique. To demonstrate the performance of the developed automatic ultrasonic examination system, low pressure turbine blades in the 2nd and 3rd stages of nuclear power plants were examined using the developed system. Its applicability nuclear power plant turbine roots of various types was also confirmed.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2005.11a
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• pp.289-292
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• 2005

Because of accumulation of operation time, the performance of main components(compressor, combustor, turbine, etc.) come to be deteriorated in gas-turbine engine. So, high reliability and minimun of expense are important problem for engine manufacturer and user in operation of gas-turbine engine. In this study, the diagnostic code of the engine performance using the thermodynamic sensitivity between the sensed parameters and the health parameters has been developed without an application of the commercial program. The single performance deterioration of the turbo-shaft engine has been estimated with this code.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.433-436
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• 2010

In this paper, heat/mass transfer characteristics on a film cooled stationary rotor blade are investigated using the naphthalene sublimation method. A row-speed annular wind tunnel with a single annular turbine stage is used. Three rows of film cooling holes are machined on the leading edge of the test blade. Detailed heat/mass transfer distributions are measured with changing the blowing rate from 1.0 to 2.0. As the blowing ratio increases, overall heat/mass transfer increases and the lower peak formed on the pressure side were disappeared.

• Journal of the Korean Institute of Gas
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• v.27 no.4
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• pp.85-91
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• 2023

In this study, an experimental study was conducted on the flame behavior, combustion dynamics, and NOx emission characteristics for hydrogen co-firing with the EV burner which is the first stage combustor of GT24. It was confirmed that as the hydrogen co-firing rate increases, the NOx emission increases. This change was elucidate to be the result of a combination of changes in penetration depth due to changes in fuel density, reduction in fuel mixing due to changes in flame position due to increased flame propagation speed, and oscillation of fuel mixedness due to combustion instability. Through pressurization tests in the range of 1.3 to 3.1 bar, NOx emission characteristics under high-pressure operating conditions were predicted, and based on this, the hydrogen co-firing limits of the EV burner was evaluated.

• Proceedings of the KIEE Conference
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• 2003.04a
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• pp.369-372
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• 2003

풍력발전 시스템은 계통에 전력을 공급하는 분산형 전원형태가 대부분이어서 어느 분산형 전원보다 계통 연계시 선로에 미치는 영향이 큰 발전설비이다. 특히 가변속 시스템인 경우 풍속이 낮은 영역에서도 운전이 가능하다는 장점이 있지만 저풍속 영역에서 풍속 변동시 터빈 회전자 출력의 리플이 직류단 전압을 변동하게 만든다. 기존의 직류단 전압 일정제어기를 사용하는 경우 인버터 출력전류는 정현파가 아닌 고조파 리플을 포함하는 문제가 발생한다. 본 논문에서는 이러한 문제점을 해결하고자 직류단 전압에 저역통과 필터를 사용하여 인버터 출력전류의 리플 개선을 하였다.

• Journal of the Korean Society of Propulsion Engineers
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• v.24 no.1
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• pp.47-57
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• 2020

The present study investigates to improve the film cooling performance on the vane endwall. Numerical simulation was conducted to analyze film cooling characteristics on the vane endwall. Six different hole arrangements were designed considering flow characteristics on the endwall. The results showed that the film cooling effectiveness was low on the pressure side and nozzle throat in the base case, because coolant was deflected from the pressure side to the suction side. On the other hand, when the holes were installed near the pressure side, the film cooling effectiveness was enhanced on the pressure side and nozzle throat, because the coolant was less affected by cross flow. Therefore, the film cooling effectiveness increases about 16% compared to the base hole arrangement.

• 유체기계공업학회:학술대회논문집
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• 2001.11a
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• pp.309-314
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• 2001

The high efficient steam turbine stage has been analyzed with the help of the 3-dimensional analysis tool. To increase the efficiency of steam turbine stage, the nozzle has to be designed by using the 3-dimensional stacking method. And the bucket has to be designed to cope with the exit flow of nozzle. To verify the stage design, therefore, the numerical analysis of the steam turbine stage was conducted. In this design, CFX-TASCflow was employed to predict the steam flow of the steam turbine stage. The numerical analysis was performed in parallel calculation by using the HP N4000 8 CPUs machine. The result showed the numerical analysis could be used to help to design the steam turbine stage.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.9
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• pp.2413-2422
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• 1994

The effects of compressor design conditions on the off-design performance of a single-shaft gas turbine engine have been studied. Three different geometric design conditions are considered and three different values for the specific mass flow rate at the inlet to the compressor are assumed. For each of nine compressor design, the off-design performance of the gas turbine engine is predicted using the method previously proposed by present authors. Results show that the predicted off-design performances are quite different from each other even though they have the same performance at design point: it means that compressor design conditions should be determined in consideration of the off-design performance of the engine. The specific mass flow rate at the inlet to the compressor is also shown that it might be optimized with respect to the net power of the engine.