Feedback Control of Flow Separation Using Plasma Actuator and FBG Sensor

A feedback control system for mitigating flow separation was developed by using a string-type dielectric-barrier-discharge (DBD) plasma actuator and a fiber Bragg grating (FBG) sensor. Tangential jets were induced from the string-type DBD plasma actuator, which was located at 5% chord from the leading edge of an NACA0024 airfoil. The FBG sensor was attached to the interior surface near the root of the cantilever beam modeled on the pressure surface of the airfoil. The strain at the cantilever root was reflected in the form of Bragg wavelengths (λB) detected by the FBG sensor when the cantilever tip was vibrated by the flow near the trailing edge of the airfoil. It was found that calculating running standard deviations in the Bragg wavelength (λB′) detected by the sensor was valuable for judging flow separation in real time. The feedback control of flow separation on the NACA0024 airfoil was successfully demonstrated by setting λB′=0.0028 with periodic flow separations generated in a wind tunnel by oscillating a side wall of the test section with frequency fw=0.42 Hz. It was confirmed that the appearance probability of flow separation tends to decrease with a decrease in the duration for calculating λB′ and with an increase in the duration of jet injection

AJK2011-13010 ACTIVE CONTROL OF FLOW SEPARATION OVER A NACA0024 AIRFOIL BY DBD PLASMA ACTUATOR AND FBG SENSOR

ABSTRACT Dielectric barrier discharge plasma actuators (DBD-PA) and fiber Bragg grating flow sensors (FBG-FS) have been investigated for active control of flow separation around a NACA0024 airfoil. Tangential jets were produced in the vicinity of the DBD-PA slightly aft of the leading edge of the airfoil. The flow separation control ability was evaluated at a low Reynolds number, Re = 5.0×10 When unaided by the DBD-PA system, flow separations from NACA0024 airfoil are suppressed significantly for certain Reynolds numbers and angles of attack. FBG-FS attached a chord-wise cantilever near the trailing edge of the airfoil was used to measure strain fluctuations for its feasibility to detect flow separation in real time and construct feedback control system with DBD-PA. In this study, it was found that standard deviations of strain fluctuations increase obviously in cases of flow conditions at which the flow around NACA0024 airfoil separates

前立腺原発印環細胞癌の1例

前立腺原発の印環細胞癌の1例を報告する.患者は, 61歳の男性, 頻尿, 排尿時痛を主訴に来院した.経尿道的前立腺生検にて印環細胞癌と判明.放射線療法, ホルモン療法, 抗癌化学療法に抵抗し, 癌性腹膜炎, 全身リンパ節転移にて, 診断後26ヵ月で死亡した.剖検にて, 前立腺原発が確認された, 免疫組織化学的には, CAI9-9およびCEAに陽性, PAPおよびPSAに陰性であった.文献上, 15例目の報告にあたる.We report a rare case of primary signet ring cell adenocarcinoma of the prostate in a 61-year-old male, who died of systemic lymphatic spread. Autopsy ruled out another primary signet ring cell adenocarcinoma outside the prostate. However, immunohistochemically, the tumor stained negatively for prostate-specific antigen. A review of the literature revealed only 15 case reports, including our case

前立腺特異的伸長ポリグルタミン発現増幅法 : 癌遺伝子治療の新しいアプローチ

京都大学0048新制・課程博士博士(医学)甲第7764号医博第2117号新制||医||713(附属図書館)UT51-99-G358京都大学大学院医学研究科外科系専攻(主査)教授 野田 亮, 教授 鍋島 陽一, 教授 小川 修学位規則第4条第1項該当Doctor of Medical ScienceKyoto UniversityDA

Effects of Input Voltage on Flow Separation Control for Low-Pressure Turbine at Low Reynolds Number by Plasma Actuators

Active flow control using dielectric barrier discharge (DBD) plasma actuators was investigated to reattach the simulated boundary layer separation on the suction surface of a turbine blade at low Reynolds number, Re = 1.7 × 104. The flow separation is induced on a curved plate installed in the test section of a low-speed wind tunnel. Particle image velocimetry (PIV) was used to obtain instantaneous and time-averaged two-dimensional velocity measurements. The amplitude of input voltage for the plasma actuator was varied from ±2.0 kV to ±2.8 kV. The separated flow reattached on the curved wall when the input voltage was ±2.4 kV and above. The displacement thickness of the boundary layer near the trailing edge decreased by 20% at ±2.0 kV. The displacement thickness was suddenly reduced as much as 56% at ±2.2 kV, and it was reduced gradually from ±2.4 kV to ±2.8 kV (77% reduction). The total pressure loss coefficient, estimated from the boundary layer displacement thickness and momentum thickness, was 0.172 at the baseline (actuator off) condition. The total pressure loss was reduced to 0.107 (38% reduction) at ±2.2 kV and 0.078 (55% reduction) at ±2.8 kV

Effects of Input Voltage and Freestream Velocity on Active Flow Control of Passage Vortex in a Linear Turbine Cascade Using Dielectric Barrier Discharge Plasma Actuator

Passage vortex exists as one of the typical secondary flows in turbomachines and generates a significant total pressure loss and degrades the aerodynamic performance. Herein, a dielectric barrier discharge (DBD) plasma actuator was utilized for an active flow control of the passage vortex in a linear turbine cascade. The plasma actuator was installed on the endwall, 10 mm upstream from the leading edge of the turbine cascade. The freestream velocity at the outlet of the linear turbine cascade was set to range from UFS,out = 2.4 m/s to 25.2 m/s, which corresponded to the Reynolds number ranging from Reout = 1.0 × 104 to 9.9 × 104. The two-dimensional velocity field at the outlet of the linear turbine cascade was experimentally analyzed by particle image velocimetry (PIV). At lower freestream velocity conditions, the passage vortex was almost negligible as a result of the plasma actuator operation (UPA,max/UFS,out = 1.17). Although the effect of the jet induced by the plasma actuator weakened as the freestream velocity increased, the magnitude of the peak vorticity was reduced under all freestream velocity conditions. Even at the highest freestream velocity condition of UFS,out = 25.2 m/s, the peak value of the vorticity was reduced approximately 17% by the plasma actuator operation at VAC = 15 kVp-p (UPA,max/UFS,out = 0.18)