Patents by Inventor Tomoka Tsujiuchi
Tomoka Tsujiuchi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 11718388Abstract: A flow control method is a flow control method of controlling flow around a blade of a rotary wing, a plasma actuator being disposed at the blade. The flow control method includes: determining a characteristic frequency ratio that is a characteristic value among frequency ratios, each of the frequency ratios being a ratio between an actuator driving frequency and an angle of attack changing frequency, the actuator driving frequency being a frequency of an applied voltage applied to the plasma actuator, the angle of attack changing frequency being a frequency at which an angle of attack of the blade changes in accordance with a rotation angle of the blade; setting the actuator driving frequency such that the frequency ratio becomes the characteristic frequency ratio; and applying a voltage of the set actuator driving frequency to the plasma actuator to control the flow around the blade.Type: GrantFiled: October 22, 2021Date of Patent: August 8, 2023Assignees: KAWASAKI JUKOGYO KABUSHIKI KAISHA, TOHOKU UNIVERSITYInventors: Hidemasa Yasuda, Akio Ochi, Kenji Hayama, Tomoka Tsujiuchi, Kazuyuki Nakakita, Taku Nonomura, Atsushi Komuro, Keisuke Takashima
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Publication number: 20220201832Abstract: A flow control method is a flow control method of controlling flow around a blade of a rotary wing, a plasma actuator being disposed at the blade. The flow control method includes: determining a characteristic frequency ratio that is a characteristic value among frequency ratios, each of the frequency ratios being a ratio between an actuator driving frequency and an angle of attack changing frequency, the actuator driving frequency being a frequency of an applied voltage applied to the plasma actuator, the angle of attack changing frequency being a frequency at which an angle of attack of the blade changes in accordance with a rotation angle of the blade; setting the actuator driving frequency such that the frequency ratio becomes the characteristic frequency ratio; and applying a voltage of the set actuator driving frequency to the plasma actuator to control the flow around the blade.Type: ApplicationFiled: April 2, 2020Publication date: June 23, 2022Applicants: KAWASAKI JUKOGYO KABUSHIKI KAISHA, TOHOKU UNIVERSITYInventors: Hidemasa YASUDA, Akio OCHI, Kenji HAYAMA, Tomoka TSUJIUCHI, Kazuyuki NAKAKITA, Taku NONOMURA, Atsushi KOMURO, Keisuke TAKASHIMA
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Publication number: 20220041269Abstract: A flow control method is a flow control method of controlling flow around a blade of a rotary wing, a plasma actuator being disposed at the blade. The flow control method includes: determining a characteristic frequency ratio that is a characteristic value among frequency ratios, each of the frequency ratios being a ratio between an actuator driving frequency and an angle of attack changing frequency, the actuator driving frequency being a frequency of an applied voltage applied to the plasma actuator, the angle of attack changing frequency being a frequency at which an angle of attack of the blade changes in accordance with a rotation angle of the blade; setting the actuator driving frequency such that the frequency ratio becomes the characteristic frequency ratio; and applying a voltage of the set actuator driving frequency to the plasma actuator to control the flow around the blade.Type: ApplicationFiled: October 22, 2021Publication date: February 10, 2022Applicants: KAWASAKI JUKOGYO KABUSHIKI KAISHA, TOHOKU UNIVERSITYInventors: Hidemasa YASUDA, Akio OCHI, Kenji HAYAMA, Tomoka TSUJIUCHI, Kazuyuki NAKAKITA, Taku NONOMURA, Atsushi KOMURO, Keisuke TAKASHIMA
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Publication number: 20210237862Abstract: A rotary-wing aircraft blade airfoil for use with a rotary-wing aircraft such as a helicopter. The airfoil satisfies the following four conditions: a first condition in which a blade thickness has its maximum value at a position within a range from 30% chord to 40% chord; a second condition in which a camber has its maximum value at a position within a range from 15% chord to 25% chord, and that a slope of the camber changes from decreasing into increasing at a position within a range from 45% chord to 55% chord; a third condition in which the upper blade height has its maximum value at a position within a range from 25% chord to 35% chord; and a fourth condition in which the lower blade height has its maximum value at a position within a range from 35% chord to 45% chord.Type: ApplicationFiled: October 21, 2020Publication date: August 5, 2021Applicant: KAWASAKI JUKOGYO KABUSHIKI KAISHAInventors: Hidemasa YASUDA, Tomoka TSUJIUCHI, Akihito ABE, Akio OCHI
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Patent number: 6231308Abstract: The root end is attached to the rotor head for rotationally driving. The central portion has aerodynamic characteristics depending on the leading and trailing edges and which extend linearly from the root end in parallel to each other, and the chord dimension therebetween. A planform shape of the blade tip portion is defined by the first leading edge which extends forwardly as the distance from the outboard end of the leading edge of the central portion outwardly increases, the second leading edge and the side edge which are rearwardly swept as the distance from the outboard end of the first leading edge toward outboard side outwardly increases, the first trailing edge which is curved forwardly as the distance from an outboard end of the trailing edge of the central portion outwardly increases, and the second trailing edge which is swept rearwardly as the distance from the outboard end point of the first trailing edge outwardly increases.Type: GrantFiled: September 8, 1997Date of Patent: May 15, 2001Assignee: Advanced Technology Institute of Commuter-Helicopter, Ltd.Inventors: Natsuki Kondo, Tomoka Tsujiuchi, Eiichi Yamakawa
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Patent number: 6190132Abstract: A blade root portion of a rotor blade is attached to a rotor head for rotating. A center portion linearly elongates from the blade root portion. A blade tip portion outward elongates from the center portion and has a shape which is defined by a leading edge, a side edge and a trailing edge, and has a predetermined aerofoil. In the leading edge of the blade tip portion, a swept-back angle &lgr;(r) at a distance r from the rotation center of a rotor satisfies relational expression (1) of a rotor blade length R of a rotorcraft, a maximum flight Mach number M∞ which is a flight limit speed of the rotorcraft, a blade tip Mach number MTIP which is a tip speed during hovering, and a drag divergence Mach number Mdd which is determined from the aerofoil of the blade tip portion.Type: GrantFiled: September 24, 1999Date of Patent: February 20, 2001Assignee: Advanced Technology Institute of Commuter-Helicopter, Ltd.Inventors: Eiichi Yamakawa, Atsushi Murashige, Tomoka Tsujiuchi