If the indicated speed on the radar gun is 10 feet per second and no cosine correction is made, then the actual speed of the water is 11.17 feet per second. The x and y-axis sensors generate a PWM signal internally to the accelerometer, The sensor is designed to provide a 50% duty cycle signal when it is sensing 0 g (where g is the unit of measurement of the earth's gravitational pull). The radar gun reads the frequency data from the tilt sensors, and the computer software uses this in calculating the cosine corrected angle of the angle formed by the radar device and the point where the velocity is measured. The equation is used to measure flow in locations where the construction of a hydraulic structure (flume or weir) is impractical. 1. Not all flow measuring devices ... wood, or fiberglass and can measure water over a wide variety of flow ranges. Flow Stations - These are usually a permanent structure located at a carefully selected, or constructed, stable site. The law of electromagnetic induction is also utilized, which takes the water flow as a conductor to measure the flow velocity. In its simple form the pitot tube consists of a glass tube whose lower end is bent at right angles (Fig. point velocity probe (PVP) to investigate groundwater velocity below the water table suggested that the PVP may also be capable of measuring groundwater velocity within the capillary fringe. gravity). POEM is a Pressure Operated Electronic Meter, with no moving parts, developed for gauging flooded rivers with flow rates up to 10 m/sec. The speed of the rotating wheel indicates the velocity of the current. This is a phenomenon called the cosine effect. It is an object of the invention to provide a radar gun that measures surface velocity and automatically compensates for the vertical or tilt angle of the gun with respect to the target. Basically, the current meter is a wheel having several cups or vanes which turn round due to the force of water current. RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES, Systems using the reflection or reradiation of radio waves, e.g. 1 is a side elevation view of the inventive radar gun tilted down at a 45Â° angle. The Coriolis Flow Meter There are many different types of meters by the most common is the Pygmy meter, the vortex meter, the flow probe, and the current meter: They are briefly described below. While the invention has been described in conjunction with a specific embodiment, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing description. At the same time that the microprocessor is receiving a reading from the y-axis sensor, Turning to FIG. In such cases it is essential to measure depth and velocity and then determine the flow measurement. Copyright, NIWA. FIG. a processor mounted in the radar gun to receive the output signal. Water flow instruments range from small acoustic doppler current profiling devices or small prop type meters for measuring very low flows in small streams, up to NIWA's flood-gauging POEM. “The device is a more efficient and inexpensive way to measure evaporation when compared with existing methods,” Bengaluru-based IISc said in a statement on Friday. x-axis and y-axis). Larger flumes are constructed on site, while smaller flumes can be ... can operate in flat ditches, are relatively insensitive to approach velocity, and are self-cleaning due to the high velocity of water passing through. There are also a few less commonly used devices, such as a radar setup that measures the velocity of waves and micro-waves on the surface of the water. There are several types of open channel flow meters, the traditional methods using primary devices such as flumes or weirs. “The device is a more efficient and inexpensive way to measure evaporation when compared with existing methods,” Bengaluru-based IISc said in a statement on Friday. When the target's path (the water flow direction) is not parallel with the gun's antenna, the radar device displays a speed which is lower than the actual water surface velocity. A sound velocity probe is a device that is used for measuring the speed of sound, specifically in the water column, for oceanographic and hydrographic research purposes. The USGS has been doing this since 1889, when it established its first stream gage on the Rio Grande River in New Mexico to determine how much water was availabl… a tilt sensor mounted in the radar gun to provide an output signal that includes a tilt angle component. The water velocity probe consists of a protected water turbo prop positive displacement sensor coupled to an expandable probe handle with a digital readout display. The formula utilizes the cross-sectional average velocity, hydraulic radius, roughness coefficient, and the slope of the channel. A radar device for measuring the surface velocity of water moving in a horizontal plane in which the radar device is positioned above or below the horizontal plane. The radar device then determines the target speed from the difference between the transmitted and reflected signal. It is a related object to provide a radar gun with automatic tilt or vertical angle correction so that the gun can be positioned above the water surface, minimizing the hazardous risks to the operator if the operator was required to stand in the moving water. 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