• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.1
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• pp.20-26
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• 2014

It is essential to consider the effect of blade deformation in order to design a better tidal stream turbine being operated in off-design condition. Flow load causes deformation on the blade, and the deformation affects the turbine performance. In the present study, CFD analysis procedures were developed to predict open water performance of horizontal axis tidal stream turbine (HATST). The developed procedures were verified by comparing the results with existing experimental results. Fluid-structure interaction (FSI) analysis method, based on the verified CFD procedure, have been carried out to estimate the turbine performance for a turbine with flexible composite blades, and then the results were compared with those for rigid blades.

• Journal of the Korean Society of Propulsion Engineers
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• v.19 no.3
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• pp.29-38
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• 2015

In this study, 3-dimensional URANS simulation was performed to analyze the effect of the nozzle-rotor axial gap spacing of a supersonic impulse turbine on turbine performance. The computations were conducted for four different axial gap cases corresponding to about 6%, 10%, 20% and 30% of the blade height, respectively. The results show a good agreement with previous studies and the turbine efficiency decreases drastically in certain range. It is examined that the turbine performance characteristics could change depending on the influence of leading edge shock to the nozzle outlet. It is also found that the entropy rise distributions along the span differ from each other.

• Plant Journal
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• v.13 no.4
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• pp.48-50
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• 2017

A program for analyzing the transient behaviors of industrial gas turbines was developed. Each component (compressor, combustor, turbine and ducts)of gas turbine is modeled as a fully module to enhance the expandability of the program. We used object-oriented programing for this purpose. The mass and energy balance equations are solved numerically by Multivariable Newton Raphson method. The characteristic maps for the compressor and turbine were used for predicting the performance of a gas turbine engine. Combustion in the combustor is assumed to be complete combustion. PID control is used to maintain constant rotational speed and turbine exhaust temperature by the control of the fuel flow rate and the changing of the compressor inlet guide vane angle at the same time. It was confirmed that stable control of the gas turbine was possible, even for a rapid load change.

• Journal of the Korean Society of Propulsion Engineers
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• v.12 no.6
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• pp.48-55
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• 2008

We have simulated the performance of a simple engine model with a gas turbine engine simulation program based on CFD. 2-dimensional Navier-Stokes code for the viscous flow was applied to simulate a compressor and a turbine, and the chemical equilibrium code with the lumped method was applied to simulate the combustor. Unsteady-flow phenomenon between rotor and stator of the compressor and the turbine was analyzed by steady mixing-plane method. In this way, the influence of the turbine blade pitch on the engine was investigated. It was shown that the compressor is operated at more higher pressure conditions as narrower the pitch distance of the turbine.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.2
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• pp.171-179
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• 2012

Cooling of hot sections, especially the turbine nozzle and rotor blades, has a significant impact on gas turbine performance. In this study, the influence of precooling of the cooling air on the performance of gas turbines and their combined cycle plants was investigated. A state-of-the-art F-class gas turbine was selected, and its design performance was deliberately simulated using detailed component models including turbine blade cooling. Off-design analysis was used to simulate changes in the operating conditions and performance of the gas turbines due to precooling of the cooling air. Thermodynamic and aerodynamic models were used to simulate the performance of the cooled nozzle and rotor blade. In the combined cycle plant, the heat rejected from the cooling air was recovered at the bottoming steam cycle to optimize the overall plant performance. With a 200K decrease of all cooling air stream, an almost 1.78% power upgrade due to increase in main gas flow and a 0.70 percent point efficiency decrease due to the fuel flow increase to maintain design turbine inlet temperature were predicted.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.281-284
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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 has been developed by KARI (Korea Aerospace Research Institute). The measurement parameters of Smart UAV propulsion system are gas generator rotational speed, power turbine rotational speed, exhaust gas temperature and torque. But two measurement such as compressor exit pressure and compressor turbine exit temperature were added because they were difficult each component diagnostics using the default measurement parameter. The performance parameters for the estimate of component performance degradation degree are flow capacities and efficiencies for compressor, compressor turbine and power turbine. Database for network learning and test was constructed using a gas turbine performance simulation program. From application results for diagnostics of the PW206C turboshaft engine using the learned networks, it was confirmed that the proposed diagnostics could detect well the single fault types such as compressor fouling and compressor turbine erosion.

• Journal of the KSME
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• v.49 no.9
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• pp.52-57
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• 2009

이 글에서는 차세대 증기터빈 개발에 대해서 먼저 소개하고 이에 따른 증기터빈의 고온 고압화, 긴 블레이드의 개발 그리고 이에 수반되는 내부효율 향상을 소개하고자 한다.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.33 no.3
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• pp.234-240
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• 1997

터보 챠저의 반동도와 터빈 노즐유량의 변화를 행하여 엔진의 성능을 향상시킬 수 있었다. 터빈의 에너지 손실과 그 영향을 미치는 반동도 및 터빈 입구의 유로의 변화, 그리고 블레이드에서 역 유동에 대한 개선 조건도 제시하였다.

• Journal of Aerospace System Engineering
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• v.11 no.1
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• pp.8-13
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• 2017

This study was performed to evaluate the turbine performance of a turbopump in the third stage engine of the Korea Space Launch Vehicle-II. The turbine is a supersonic impulse type with a single rotor. One nozzle is for starting and four remaining nozzles are for steady operation. A similarity test was carried out in the high air test facilities at the Korea Aerospace Research Institute. Test results showed that turbine efficiency changed much more from rotational speed variations than by pressure ratio variations. These results showed characteristics similar to other supersonic impulse turbines.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.15 no.1
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• pp.69-75
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• 2022

Due to the increase in the demand for anomaly detection according to the ageing of power generation facilities, the need for developing an anomaly detection method that can provide high-reliability turbine blade anomaly detection performance has been continuously raised. Additionally, the false detection results caused by a human error accelerates the increase of the need. In this paper, we propose an anomaly detection technique for turbine blades in power plants using deep neural networks. Experimental results prove that the proposed technique achieves stable anomaly detection performance while minimizing human factor intervention.