A device of a dual floating anemometer comprised of a mast, support arms for instruments, purlins, a central buoy, connecting beams, the edge floaters, the buoy hoop, the buoyanchorage connector, anchorage hoop, anchorage, wind measuring instruments A, the connector beam of the anemometer base B, the wind instrument base B wind measuring instruments B, the anchorages of the edge floaters, the connections of the anchorages of the edge floaters with the edge floaters and the connector hoops of the anchorages with the edge floaters, which can be placed in shallow or big water depths and can simultaneously measure the characteristic wind parameters using both common anemometers and Doppler anemometers, so that the measurements of the wind potential (velocity, direction, turbulence) are extended to a higher altitude than the altitude of the mast which bears the cup anemometers, because of the combinatorial action.

A method for determining a flow speed of a liquid in a fluid conduit is provided. During a signal-generating phase, an impulse signal is applied to a first ultrasonic transducer. A response signal is then received at a second ultrasonic transducer. A measuring signal is later derived from the response signal, wherein the derivation comprises reversing a signal portion with respect to time. During a measurement phase, a liquid moves with respect to the fluid conduit. The measuring signal is then applied to one of the two transducers and a response signal of the measuring signal is measured at the other transducer. A flow speed is derived from the response signal of the measuring signal.

A method for determining a flow speed of a liquid in a fluid conduit is provided. During a signal-generating phase, an impulse signal is applied to a first ultrasonic transducer. A response signal is then received at a second ultrasonic transducer. A measuring signal is later derived from the response signal, wherein the derivation comprises reversing a signal portion with respect to time. During a measurement phase, a liquid moves with respect to the fluid conduit. The measuring signal is then applied to one of the two transducers and a response signal of the measuring signal is measured at the other transducer. A flow speed is derived from the response signal of the measuring signal.

A three-dimensional flow velocity vector, energy and mass gauge is provided, wherein it comprises an elastic leather cover, both ends of which are mounted with a rigid sealing plug, separately, the elastic leather cover and the rigid sealing plug forming a cylindrical sealing cavity, in which a cable connecting line hole is installed on the upper rigid sealing plug, while an injection hole for injecting liquid into the cylindrical sealing cavity, on which a sealing plug is provided, is installed on the lower rigid sealing plug; and a measuring device for measuring the flow velocity vector and energy and a device for measuring the mass are installed in the cylindrical sealing cavity. The gauge has the advantages of a simple structure, convenient manufacturing and comprehensive detection.

A grain cleaning system for a combine harvester having a transmitter adapted to transmit a base signal at a known frequency and one or more spaced receivers for detecting signals of a different frequency as reflected from airborne grain and other materials within the duct of the grain cleaning system. An Electronic Control Unit modulates the base signal and the reflected signals to obtain Doppler signals or frequencies from which an average particle velocity is determined. The particle velocity is used as an input parameter for the generation of control signals for the adjustment of various working units of the combine harvester including, by way of example, the fan and sieves.

A clamp-on ultrasonic flowmeter includes pairs of ultrasonic transducers arranged on an exterior of a pipeline, and an electronic measuring/operating circuit for operating the transducers and for registering and evaluating measurement signals and for providing measured values of volume flow or flow velocity. The pairs are implemented as 1-traverse or 2-traverse pairs. One-traverse pairs are arranged on opposite sides of the pipeline, and 2-traverse pairs are arranged on a same side of the pipeline. At least three pairs are arranged on the pipeline and are distributed peripherally. Adjoining pairs of a number of pairs have an inner angle down to a minimum inner angle (MIA) between one another measured about a pipeline axis, which minimum inner angle obeys the following relationship:
MIA=360/(T*N*F(T,N))
with T as number of traverses and F(T,N)=0.38+0.62*T+(0.0480.01*T{circumflex over ()}2)*(N2){circumflex over ()}2.

A fluid device includes a flow path through which a fluid flows, and an ultrasonic element that transmits an ultrasonic wave to the fluid to generate a standing wave in the fluid in the flow path along a first direction orthogonal to a flowing direction of the fluid. The ultrasonic element includes a vibrator having a fluid contact surface that comes into contact with the fluid, and a piezoelectric element that is provided at the vibrator and that flexurally vibrates the vibrator in a normal direction of the fluid contact surface. When a thickness of the vibrator in the normal direction is t, a sound velocity of a medium of the fluid is C, an average sound velocity of a longitudinal wave transmitted in the vibrator is C, a dimension of the flow path in the first direction is L, and a mode order of the standing wave is n, the following expression is satisfied. $t<\frac{C^{}}{C}\frac{L}{2n}$

An underwater acoustic receiver apparatus (100) comprises an acoustic reflector (102, 104, 106, 108) and an acoustic device (110, 114, 116, 118) aimed at the acoustic reflector (102, 104, 106, 108). The acoustic reflector (102, 104, 106, 108) is disposed at a predetermined distance and orientation relative to the acoustic device (110, 114, 116, 118).

A fluid device 10 includes: a flow path 20 through which a fluid containing a fine particle flows; an ultrasonic transmitter 60 configured to transmit an ultrasonic wave to the fluid in the flow path 20 in response to an input of a drive signal; a flow velocity measurement unit 40 configured to measure a flow velocity of the fluid in the flow path 20; and a controller 70 configured to control the ultrasonic transmitter 60. The controller 70 sets an amplitude of the drive signal according to a measured flow velocity that is a flow velocity measured by the flow velocity measurement unit 40, and inputs the drive signal having the set amplitude to the ultrasonic transmitter 60.