• 한국기계가공학회지
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• 제13권4호
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• pp.113-120
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• 2014

To ventilate indoor spaces, axial single-blade fans are widely used in various areas, such as schools, houses, offices, and restaurants. Recently, axial single-blade fans were developed to realize energy efficiency and noise reduction improvements. Here, an experimental study of the air flow characteristics of an axial dual-blade fan is conducted. The characteristics of the axial dual-blade fan were tested via an air flow analysis and with prototypes. For the performance of the fan, the flow rate, power consumption, and noise were evaluated. The result showed that the axial dual-blade fan uses less power and produces less noise in comparison with an axial single-blade fan.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.63.2-63.2
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• 2011

The objective of this study is to investigate the aerodynamic characteristics of a small vertical axis wind turbine with dual blade type. The Wind turbine with dual blade has various angle of attack. so this turbine improve starting characteristics. The various arrangement of the vertical axis wind turbine with dual blade is designed. Among them, it shows superior quality that is arranged in three rows. Among arrangement in three rows, we use general computational fluid dynamics program CFX to find out the optimal arrangement. By comparing the predicted results of the aerodynamic characteristics of the different arrangement of the blades, an appropriate arrangement of the blade is suggested to design the small wind turbine blade.

• 대한기계학회논문집A
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• 제36권3호
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• pp.297-304
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• 2012

블레이드의 성능 평가를 위하여 실제 사용 환경과 근접한 하중 모사에 따른 이축 하중의 필요성이 제기되고 있으며, 본 본문에서는 이러한 이축 하중에 따른 블레이드의 거동을 해석하였다. 100kW급 풍력 블레이드를 대상으로 하였으며, ANSYS를 사용하여 정적거동을 분석하였다. 정적거동은 파손해석과 좌굴거동으로 분석하였으며, 파손 평가는 Puck이 제안한 파손 방정식을 이용하여 섬유 파손과 섬유간 파손 기준을 검토하였다. 이축하중의 하중비가 증가함에 따라 루트부 단면이 변하는 후연부와 루트에서 Z+ 3300~3600인 지점에서 응력이 상대적으로 크게 나타났다. 또한 이축 하중비가 증가함에 따라 블레이드 좌굴 지점이 루트부 쪽으로 이동되고 있음을 확인하였다. 따라서 블레이드의 사용 신뢰성을 검증하기 위해서는 이축 하중에 의한 시험이 요구되고 있음을 본 해석을 통해서 확인하였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 추계학술대회 논문집
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• pp.366-368
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• 2007

Mr. Hur has developed the 7500KW permanent magnet synchronous generator. The 7500KW generator has dual blade system with vertical axis type generation module. The 7500KW generator will generating that it is too expensive and construction payment. The advantages of dual blade system are cheap in generation with better efficiency, and safety compact structure. But also this system has the expensive slide ring for to distribute electrical power.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.495-499
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• 2009

본 논문에서는 상호역회전 풍력발전기와 New Yaw System 실증시험에 대하여 제시한다. 상호역회전 풍력발전기는 공기의 유동을 가진 운동에너지의 공기역학적(aerodynamic) 특성을 이용하여 동일한 바람방향에 대해 상호 반대방향으로 회전하는 Front Blade와 Rear Blade를, Generator의 Rotor와 Stator에 각각 결합 형성한 것으로, Generator와 Dual Blade의 회전력이 원심력이 아닌 구심력으로 변환되어 무게중심이 균형을 이루게 한다. 이렇게 변환된 구심력은 회전구동부분의 편마모 현상, 소음발생 현상 및 불균형 톨크 발생 현상 감소효과가 공히 구현되도록 하여 풍력발전기의 구조적 안정성 및 발전효율 증대효과를 얻을 수 있도록 한 기술이다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2011년도 춘계학술대회 논문집
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• pp.463-464
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• 2011

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 추계학술대회 논문집
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• pp.861-864
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• 1997

Singulation is a process that cutting for separating a chip individually after finishing packaging process(micro BGA etc.). For shortening the process of singulation, we proposed the singulation using multi-blade. This paper introduced a method of multi-blade singulation and investigated a result of application and problems. The efficiency of singulation process was improved five times better than the single-blade by the singulation using Multi-blade.

• 한국유체기계학회 논문집
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• 제15권2호
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• pp.63-68
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• 2012

This paper deals with the aerodynamic analysis and structural test under estimated loading condition for small composite blade, which is utilized in dual rotor wind turbine system. Firstly, the front and rear blades of dual rotor wind turbine system were modeled using reverse engineering method. And using finite volume method, the aerodynamic forces were analyzed at the rated and cutout wind speed to identify the pressure distribution on blades. And then, the full scale structural tests were conducted according to load and strength based methodology in IEC 61400-2 to identify the structural integrity of composite blade.

• Tribology and Lubricants
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• 제36권2호
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• pp.105-115
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• 2020

This paper presents a numerical study on the rotordynamic analysis of a dual-spool turbofan engine in the context of blade defect events. The blades of an axial-type aeroengine are typically well aligned during the compressor and turbine stages. However, they are sometimes exposed to damage, partially or entirely, for several operational reasons, such as cracks due to foreign objects, burns from the combustion gas, and corrosion due to oxygen in the air. Herein, we designed a dual-spool rotor using the commercial 3D modeling software CATIA to simulate blade defects in the turbofan engine. We utilized the rotordynamic parameters to create two finite element Euler-Bernoulli beam models connected by means of an inter-rotor bearing. We then applied the unbalanced forces induced by the mass eccentricities of the blades to the following selected scenarios: 1) fully balanced, 2) crack in the low-pressure compressor (LPC) and high pressure compressor (HPC), 3) burn on the high-pressure turbine (HPT) and low pressure compressor, 4) corrosion of the LPC, and 5) corrosion of the HPC. Additionally, we obtained the transient and steady-state responses of the overall rotor nodes using the Runge-Kutta numerical integration method, and employed model reduction techniques such as component mode synthesis to enhance the computational efficiency of the process. The simulation results indicate that the high-vibration status of the rotor commences beyond 10,000 rpm, which is identified as the first critical speed of the lower speed rotor. Moreover, we monitored the unbalanced stages near the inter-rotor bearing, which prominently influences the overall rotordynamic status, and the corrosion of the HPC to prevent further instability. The high-speed range operation (>13,000 rpm) coupled with HPC/HPT blade defects possibly presents a rotor-case contact problem that can lead to catastrophic failure.

• 제어로봇시스템학회논문지
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• 제15권12호
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• pp.1240-1245
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• 2009

The throughput characteristics of the cluster tool with dual blade robot are analyzed. Using equipment's cycle time chart of the equipment, simple analytic form of the throughput is derived. Then, several important throughput characteristics are analyzed by the throughput formula. First, utilization of the process chamber and the robot are maximized by assigning the equipment to the process whose processing time is near the critical process time. Second, rule for selecting optimal number of process chambers is suggested. It is desirable to select a single process chamber plus a single robot structure for relatively short time process and multi process chambers plus a single robot, namely cluster tool for relatively long time process. Third, throughput variation between equipments due to the wafer transfer time variation is analyzed, especially for the process whose processing time is less than critical process time. And the throughput and the wafer transfer time of the equipments in our fabrication line are measured and compared to the analysis.