• International Journal of Fluid Machinery and Systems
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• 제4권1호
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• pp.97-103
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• 2011

With the aim to increase blade loadings and stable operating range in highly loaded compressors, this article has been conducted to explore, through a numerical parametric study, the potential of passive control using slotted bladings in cascade configurations. The objective of this numerical investigation is to analyze the influence of location, width and slope of the slots and therefore identify the optimal configuration. The approach is based on two dimensional cascade geometry, low speed regime, steady state and turbulent RANS model. The results show the efficiency of this passive technique to delay separation and enhance aerodynamic performances of the compressor cascade. A maximum of 28.3% reduction in loss coefficient have been reached, the flow turning is increased with approximately $5^0$ and high loading over a wide range of angle of attack have been obtained for the optimized control parameter.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2010년도 제35회 추계학술대회논문집
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• pp.101-104
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• 2010

최근 무인기 혹은 소형 항공기들에 대한 수요가 증가함에 따라 소형 터보제트 혹은 터보팬 엔진의 수요가 꾸준히 증가하고 있다. 이러한 소형 엔진은 요구 추력을 달성하면서 크기와 무게를 줄이는 것이 가장 중요한 설계 인자인데, 이는 곧 비추력(Thrust to Weight) 값이 매우 높음을 의미한다. 비추력 값이 높은 엔진을 설계하기 위해서, 압축기 혹은 터빈 등의 핵심구성품의 경우 크기를 줄이고 단수를 줄이는 방법이 가장 효과적이다. 특히 축류압축기의 경우 일반적으로 다단으로 구성하는데 여러 단으로 구성된 압축기 중에서 단수를 줄이고 남은 단에서의 압력비를 높이는 '고부하 압축기'를 채용함으로써 이러한 문제를 해결할 수 있다. 최근 국내에서도 축류형 압축기에 대한 개발의 필요성이 꾸준히 제기되고 있으며, 이에 본 논문에서는 고부하 축류형 압축기의 설계 및 성능 리뷰 중 주요한 사항에 대해 소개하고자 한다.

• 한국유체기계학회 논문집
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• 제15권2호
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• pp.12-19
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• 2012

This study presents unsteady and unstable characteristics of three stage transonic axial compressor, developed by Korea Aerospace Research Institute. As approaching to the unstable operating region at the 103% design speed of the compressor, a modal type stall precursor appears in front of highly loaded 3rd rotor row at first, and it propagates to the upstream. On the contrary, actual stall cell initiates from the stall precursor in front of the 1st rotor row, and it propagates to the downstream of the compressor. After the stall region reached the 3rd stage and stall cell rotates circumferentially about 360 deg, it develops to one dimensional compressor surge mode. It shows a mild surge behaviour with 3~4 Hz frequency. From the test data, it can be suggested that there is a priority to give an optimum blade loading distributions to construct a multi stage transonic axial compressor stages either to secure more stable compressor operating ranges, or to maximize the compressor efficiency.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2001년도 유체기계 연구개발 발표회 논문집
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• pp.149-155
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• 2001

Recently, it is required to design higher stage pressure ratio compressor while maintaining equal adiabatic efficiency. To increase the stage pressure ratio, blade rotational speed or diffusion factor should be increased. In the case of increasing rotational speed, relative speed of flow at blade leading edge is well supersonic. In supersonic blade, total pressure loss is mainly due to shock wave and blade leading edge thickness should be very thin to minimize the shock wave loss. As a result, the blade is like to be week in terms of mechanical strength and the manufacturing cost is very high because NC machining is necessary. It is also one of big hurdle to overcome to make small compressor. In this paper, the effects of blade leading edge to the performance of supersonic blade In terms of total pressure loss. The efficiency of already known method to make thin blade leading edge from the casted blade with rather thick leading edge thickness is also assessed.