A multirotor drone comprises a main body and an air channel embedded within the main body having an air inlet on the surface of the main body, multiple propellers that induce an air flow toward the air inlet and into the air channel, a microcontroller positioned and configured to control navigation of the drone by actuation of the plurality of propellers, an air scoop having a section positioned at the outer surface of the main body adjacent to the air inlet which is adjustable so as to capture and divert air into the air inlet and air channel or to block air flow into the air inlet, and a gas sensor positioned within the air channel. The air scoop is positioned to capture air flow from at least one of the plurality of propellers into the air channel and to the gas sensor.

A method of estimating a parameter of a fluid flowing in a passage includes: having a plurality of instruments operable to measure one or more fluid properties flowing in the passage, the plurality of instruments being disposed in the passage and arranged within a common measurement plane; assigning a stream tube to each instrument, each stream tube represents a region of space in the common measurement plane within the passage and each stream tube surrounds one of the plurality of instruments, the stream tubes together correspond to the cross-sectional shape and area of the passage in the common measurement plane; measuring the one or more fluid properties using the instruments to obtain one or more measured values for each stream tube; using the measured value(s) for each stream tube to calculate a derived value for each stream tube; and summing the derived values across all of the stream tubes.

A method of estimating a parameter of a fluid flowing in a passage includes: having a plurality of instruments operable to measure one or more fluid properties flowing in the passage, the plurality of instruments being disposed in the passage and arranged within a common measurement plane; assigning a stream tube to each instrument, each stream tube represents a region of space in the common measurement plane within the passage and each stream tube surrounds one of the plurality of instruments, the stream tubes together correspond to the cross-sectional shape and area of the passage in the common measurement plane; measuring the one or more fluid properties using the instruments to obtain one or more measured values for each stream tube; using the measured value(s) for each stream tube to calculate a derived value for each stream tube; and summing the derived values across all of the stream tubes.

A boundary layer control (BLC) system for embedment in a flight surface having a top surface, a bottom surface, a leading edge, and a trailing edge. The BLC system may comprises an actuator having a crossflow fan and an electric motor to drive the crossflow fan about an axis of rotation. The actuator may be embedded within the flight surface and adjacent the leading edge. In operation, the actuator is configured to output local airflow via an outlet channel through an outlet aperture adjacent the top surface to energize a boundary layer of air adjacent the top surface of the flight surface.

A lift-changing mechanism is configured to change generated by a wing of an aircraft and includes a slit and an opening and closing member. The slit extends in a wingspan direction inside the wing and forms openings on the lower surface of the wing and on the upper surface of the wing respectively. A part of airflow below the lower surface is allowed to flow toward the upper surface through the slit. The opening and closing member is configured to open and close the slit. When the opening and closing member opens the slit, lift generated on the wing is decreased compared with when the slit is closed.

A leading edge structure for an aircraft flow control system includes a leading edge panel curvingly surrounding a plenum. The leading edge panel has a first side portion and a second side portion with an inner surface facing the plenum and an outer surface contacting an ambient flow. The leading edge panel includes a plurality of micro pores forming a fluid connection between the plenum and the ambient flow. An air outlet is arranged in the first or second side portion and is fluidly connected to the plenum for letting out air from the plenum into the ambient flow. The air outlet is formed as a fixed air outlet including an outlet panel extending in a fixed manner from the leading edge panel into the ambient flow, such that a rearward facing outlet opening is formed between the leading edge panel and a rear edge of the outlet panel.

The present disclosure provides systems, apparatuses, and methods relating to a fan apparatus including a lift fan mounted in a duct and a cover for the lift fan. In some examples, a fan apparatus has a louvered cover including louvers having different chord lengths and/or different projection distances relative to one another when the louvers are in an intermediate (transitional) position. In some examples, a fan apparatus includes a louver actuation assembly configured to move louvers of the fan apparatus rotationally and translationally between open and closed positions. In some examples, a fan apparatus includes a fluid-actuated sealing assembly configured to form a seal between a sealing member and a cover, such as a louvered cover.

The present disclosure provides systems, apparatuses, and methods relating to a fan apparatus including a lift fan mounted in a duct and a cover for the lift fan. In some examples, a fan apparatus has a louvered cover including louvers having different chord lengths and/or different projection distances relative to one another when the louvers are in an intermediate (transitional) position. In some examples, a fan apparatus includes a louver actuation assembly configured to move louvers of the fan apparatus rotationally and translationally between open and closed positions. In some examples, a fan apparatus includes a fluid-actuated sealing assembly configured to form a seal between a sealing member and a cover, such as a louvered cover.

Air acceleration at slot of aircraft wing. In one embodiment, a wing includes an air duct configured to transport air in a spanwise direction along a leading edge of the wing from an air supply source of the aircraft. The wing further includes a discharge duct configured to transport the air in an aft direction from the air duct to an aft end of the wing, and one or more nozzles disposed on the aft end of the wing and configured to accelerate air into a slot between the wing and a flap of the aircraft to increase lift and reduce drag for the wing.

A fluid adjustment device is provided with: a body part mounted on a wing tip, which is an end part of a main wing on the opposite side to the wing root, and having an upper opening and a lower opening formed in an upper surface of the body part and a lower surface of the body part; a first Francis turbine that sucks air from the upper opening and the lower opening and discharges the sucked air from the trailing edge side of the main wing; and a first motor for rotating the first Francis turbine in a direction opposite to a rotation direction of a wingtip vortex generated at the wingtip. The first Francis turbine has a central axis extending from the leading edge of the main wing toward the trailing edge, sucks air from the circumferential direction, and discharges the sucked air in the axial direction.