• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 1999.10a
• /
• pp.26-26
• /
• 1999

소·중형 산업용 항공기나 초등 훈련기용으로 많이 이용되고 있는 터보프롭 엔진의 성능진단을 위해 선형 GPA 기법을 적용하였다. 대기조건은 지상정지조건으로 하였으며 계측변수의 선정에 따른 오차율을 알아보기 위해 다양한 손상을 가정하였다. 가스터빈 엔진에서 가장 쉽게 발견될 수 있는 성능저하 원인인 압축기 오염과 터빈 부식이 발생하였을 경우를 가정하였다. 다중 손상일 경우 선형 GPA 기법의 신뢰성을 알아보기 위해 압축기에만 오염이 발생하였을 경우, 압축기와 압축기 터빈에 각각 오염과 부식이 발생하였을 경우, 압축기 터빈과 동력터빈에 동시에 부식이 발생하였을 경우, 압축기, 압축기 터빈, 동력터빈이 모두 오염과 부식이 발생하였을 경우를 가정하였다.

• Aerospace Engineering and Technology
• /
• v.6 no.2
• /
• pp.197-204
• /
• 2007

Effect of rotor tip geometry on the performance of supersonic impulse turbine was investigated experimentally. Using the shrouded supersonic impulse turbine of the 30ton class liquid rocket engine turbopump as a base model, the measured performance of de-shrouded rotor was compared. The effect of nozzle-rotor overlap also has been investigated. It has been found that the magnitude of turbine efficiency is largely affected by the existence of the rotor shroud. However, measured efficiency sensitivity of the de-shrouded supersonic impulse turbine with respect to turbine tip clearance was relatively smaller than that of high performance reaction turbine. It also has been found that there exists nozzle-rotor overlap value which results optimum efficiency in supersonic impulse turbine.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.10 no.2
• /
• pp.78-86
• /
• 2006

This paper presents the performance test result of the 30-ton class turbopump turbine. Test has been conducted using high pressure cold air, The turbine overall performance has been measured for various pressure ratio and rotational speed settings. The nozzle-rotor clearance effect on turbine performance also has been tested for the four kinds of the nozzle-rotor clearance values. We found that turbine efficiency rated 51.1% at its design velocity ratio and pressure ratio of 13.5. We also found that turbine efficiency can be increased by 3.5% for approximately 1mm decrement of the nozzle-rotor clearance from its nominal value.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2007.11a
• /
• pp.297-301
• /
• 2007

The blades of supersonic turbines with low aspect ratio are usually designed to have the same cross sectional shape in radial direction. The profile diameter definition of turbines may lead to produce unintended flow passage area variations resulting performance degradation. In this paper, the effects of profile diameter definition on the supersonic impulse turbine performance have been investigated. Computational results of three different profile diameters are compared. It has been found that flow passage area variation can be achieved according to designer's intention when blade profile is defined at rotor tip diameter. Furthermore, the turbine blade profile defined at rotor tip showed better performance than the others.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.37 no.9
• /
• pp.889-898
• /
• 2009

A mixed-type turbine was adopted and the rotor outer diameter was 108 mm. Turbine rotors were designed to the axial-type blade because the turbine operated at a low partial admission rate of 1.7-2.0% with two stages. Performance characteristics were studied when the spouting from the nozzle was toward radially inward or outward direction. Additionally, the effect at each stage of the rotor was measured. For comparing with each turbine performance, properties were measured based on various rotational speeds. Measured net specific torque was used to compare with the turbine system performance. On the mixed-type turbine, better performance was obtained when the operating air spouted toward radially inward direction. The specific torque was increased by 7.8% from using the second stage although its effect depended on the rotational speed.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
• /
• 1993.11a
• /
• pp.13-21
• /
• 1993

석탄가스화 복합발전 플랜트의 부속공정인 중기터빈 시스템에 대한 공정 전산해석을 상용 공정해석 소프트웨어인 ASPEN 코드를 이용하여 수행하였다. 폐열회수보일러에서 생성되는 고압증기 조건을 2400psig로 채택하였으며, 폐열회수보일러의 열교환기 배열 및 생성증기의 조건에 따른 증기터빈 시스템의 성능변화를 고찰하였다. 페열회수보일러에서의 열교환기 배열, 생성중기 조건 및 공급수 예열 방법에 따라 증기터빈 시스템의 성능이 변화하게 되므로 이의 정확한 이해를 통하여 증기터빈 시스템의 최적화를 도모할 수 있다.

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 2006.05a
• /
• pp.79-82
• /
• 2006

본 논문은 원자력 발전소의 주요 제어계통 중에서 터빈 조속기 제어계통에 관련한 성능평가를 목적으로 한다. 터빈 조속기 계통은 고압의 유압계통으로 구성되어 있어 구동설비가 복잡하다. 복잡한 기계설비는 운전 중 많은 오동작에 의한 고장을 일으키고, 유지보수에 어려움이 있다. 이러한 복잡한 기계설비에 있어 운전원에 의한 기계성능 평가는 불리한 점이 많다. 예를 들어 서로 다른 시간에서 일어나는 같은 상황에 대해 다른 판단을 내릴 수 있다는 점이다. 터빈 조속기 계통의 기계설비에 있어서 터빈 밸브 유압공급 및 구동장치는 각 터빈벨브 자체에 부착되어 있어 터빈벨브를 동작시킨다. 터빈벨브들은 구동기 유압 서보실린더(Actuator Hydraulic Servo Cylinder)에 의해 열리고 압축된 스프링에 의해 닫힌다. 이러한 시스템을 진단하기 위해서 본 논문에서는 밸브의 내부 압력의 특징정보를 입력으로 하는 퍼지이론을 적용하여 터빈 밸브 구동설비의 성능을 판단하고자 한다. 퍼지이론에 적용하기위해 터빈 조속기 제어계통의 고압 터빈 조절 벨브와 고압 터빈 정지 밸브의 압력변화 데이터를 이용한다. 퍼지이론의 적용과정에서 퍼지 Rule은 실제 운전원이 압력변화 데이터에 대한 판단기준을 근거로 하여 정하기로 한다. 그리고 퍼지이론에 적용한 결과를 분석하고 실제 터빈 조속기 계통의 전문가가 판단 결과와 비교하였다.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.19 no.2
• /
• pp.151-158
• /
• 2016

Tidal farm is a multi-arrayed turbine system for utilizing tidal stream energy. For horizontal-axis turbine(HAT) system, it is recommended that each unit has to be deployed far apart in order to avoid hydrodynamic interference among turbines, as proposed by the European Marine Energy Centre(EMEC). But there is no rule for the arrangement of vertical-axis turbine(VAT) yet. Moreover it has been reported that a proper arrangement of adjacent turbines can enhance the overall efficiency even greater than an arrangement without mutual interference effect. This paper suggests the layout of VATs showing the better performances, which turned out to be quite different from HATs' arrangement. Numerical calculations were performed to investigate the performance variation in terms of the rotational direction as well as the distance between turbines. It has been shown that the best combination of rotational direction and distance between turbines can increase its performance higher about 9.2% than that of two independently operated turbines. It is likely that such improvement is due to the increased velocity between adjacent turbines. For diagonally arranged turbines, the maximum normalized mean power coefficient was obtained to be higher about 5.6% than that of two independent turbines. It is expected that the present results can be utilized for conceptual design of tidal farm to harness the tidal stream energy.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2006.11a
• /
• pp.382-386
• /
• 2006

Three dimensional numerical analysis of the supersonic turbines with different rotor tip clearances was conducted to analyze the effect of the tip gap clearance variations on the turbine performance. The result showed that the turbine performance deteriorates and the tip leakage increases by the effect of the rotor tip clearance and the tip leakage affects turbine performance degradation dominantly.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.12 no.1
• /
• pp.1-6
• /
• 2008

Performance test of the 30-ton class liquid rocket engine turbopump turbine has been conducted using high pressure cold air. Overall performance of the two kinds of turbine rotors - rotor with knife-edged L.E blades and with rounded L.E blades - has been measured for various rotational speed and turbine pressure ratio. The effect of rotational speed and turbine pressure ratio on the turbine axial force behavior also has been measured in parallel. Test results have revealed that the efficiency of knife edged L.E. turbine is a little bit higher than that of rounded L.E. turbine. The axial force of the turbine varied linearly with respect to rotational speed and its magnitude largely depended on turbine pressure ratio.