Abstract:
PURPOSE: An FBG(Fiber Bragg Grating) sensor having a ring-shaped leaf spring fixing member, a biaxial FBG sensor having a ring-shaped leaf spring fixing member, and a manufacturing apparatus and method for the FBG sensor are provided to prevent a measurement error caused by direct contact and friction with a structure to be measured and to enable measurement of both extension and compression. CONSTITUTION: A method for manufacturing an FBG sensor having a ring-shaped leaf spring fixing member is as follows. A first fixing part(130) of a ring-shaped leaf spring(121) is fixed to a first fixing jig and a second fixing part(140) is fixed to a second fixing jig. The second fixing jig is linearly moved toward the first fixing jig so that the ring-shaped leaf spring is compressed. An optical fiber cable(160) is inserted into a slit(150) and fixed with an optical fiber fixing adhesive. The second fixing jig is linearly moved opposite to the first fixing jig after curing the adhesive so that the compression of the ring-shaped leaf spring is released.
Abstract:
PURPOSE: An optical fiber bragg grating sensor package is provided to stable maintain the angle between sensors arranging optical bragg grating sensors and be attached to the surface of the structure or be inserted into the structure. CONSTITUTION: An optical fiber bragg grating sensor package comprises a body, an optical fiber line(410), and fiber bragg grating sensors(420,420-1). The body comprises a given area of a triangular hole(440). The body has a given width of the same triangle shape to the triangular hole. The optical fiber line is arranged on the width of the body. The optical fiber bragg grating sensors are formed on the optical fiber line at an interval and an angle from the body. The number of the optical fiber bragg grating sensors is two or three. The two optical fiber bragg grating sensors are arranged along the optical fiber line arranged along the bottom side and the top side of the body at an angle of 90°.
Abstract:
PURPOSE: A method of detecting damage to a composite material using DWT is provided to analyze a reason for damage to a structure by converting a sound emitting signal using wavelet and calculating the change in the area ratio of envelope by specific component. CONSTITUTION: A method of detecting damage to a composite material using DWT is as follows. A sound emitting signal generated by damage to a structure is detected as a source signal by a sound sensor(S200). The source signal is divided into a plurality of similar components and specific components using discrete wavelet transform(S210). Only a superhigh frequency area is selected from the specific components(S220). The superhigh frequency area is only enveloped(S230). The enveloped superhigh frequency area is integrated to calculate the area of envelope of the specific components(S240).
Abstract:
PURPOSE: A system for demodulating FBG sensors using spectroscope and linearly arrayed photodetectors is provided to enable the wavelength of reflective light to be accurately measured at a time by making reflective light from the FBG sensor as spectrum using the spectroscope and by projecting the spectrum to the linearly arrayed photodetectors. CONSTITUTION: A system for demodulating FBG sensors using spectroscope and linearly arrayed photodetectors comprises a light source(110), a spectroscope(120), linearly arrayed photodetectors(130) and an analyzer(140). The light source generates and sends white light or broadband light to the FBG sensor(200). The spectroscope receives and disperses the reflective light by wavelength. The reflective light enters from the light source to the FBG sensor and then is reflected. The linearly arrayed photodetectors detect the dispersed light. The analyzer is connected to the linearly arrayed photodetectors. The analyzer processes the signal generated from the linearly arrayed photodetectors.
Abstract:
PURPOSE: A high-speed demodulation system for FBG sensors using a multi-window fabry-perot filter is provided to simultaneously measure lights reflected from multiple FBG sensors. CONSTITUTION: A high-speed demodulation system(100) for an FBG Sensor using a multi-window fabry-perot filter comprises a light source(110), a multi-window fabry-perot filter(120), an WDM coupler(130), photo detectors(140), and an analyzer(150). The light source projects white light or broadband light to FBG sensors(200). The multi-window fabry-perot filter receives the light reflected from the FBG sensors and projects the light to each filter window. The WDM coupler separates the light passing through the multi-window fabry-perot filter. The photo detectors sense each reflected light separated by the WDM coupler. The analyzer is connected to photo detectors and processes signals generated from the photo detectors.
Abstract:
PURPOSE: A rotor blade airfoil arrangement method and a rotor blade for a wind power generator are provided to minimize noises by arranging the airfoil of the rotor blade to conform with the actual flow. CONSTITUTION: A rotor blade airfoil arrangement method for a wind power generator is as follows. A specific location(r) in the span direction of a rotor blade(3) is determined and the two-dimensional profile of the airfoil is selected. The two-dimensional profile is mapped on a three-dimensional curved mapping surface(P) which is curved in the flow direction.
Abstract:
본 발명은 저풍속 실속제어/정속운전용 풍력발전기 블레이드에 관한 것으로, 더욱 상세하게는 블레이드의 에어포일 형상, 블레이드의 비틀림각 및 시위선의 길이를 최적화하여 저풍속에서 효율이 향상되는 저풍속 실속제어/정속운전용 풍력발전기 블레이드에 관한 것이다. 본 발명은 저풍속 실속제어/정속운전용 풍력발전기 블레이드에 있어서, 상기 블레이드의 에어포일은 앞전(Leading Edge)과 뒷전(Trailing Edge)을 잇는 시위선(Chord)을 기준으로 상측과 하측으로 볼록한 윗면 및 아랫면을 가지며, 상기 아랫면의 중앙부에서 뒷전까지 블레이드의 길이방향을 따라 상측으로 오목한 S테일이 형성되며, 상기 블레이드는 가장 긴 시위선을 갖는 루트에어포일; 상기 블레이드의 끝단을 형성하는 팁에어포일; 및 상기 루트에어포일과 팁에어포일 사이의 주에어포일; 로 이루어지는 것을 특징으로 한다. 상기와 같은 에어포일의 형상, 비틀림각의 분포 및 시위선의 길이 분포를 따르는 블레이드로 인하여 국내 풍황에 적합한 풍속 3~5m/s의 저풍속 영역에서 0.4 이상의 효율을 가지며, 더불어 전체 풍속영역에서의 효율이 향상되는 효과가 있다. 풍력발전기, 블레이드, 에어포일