The effect of liquid stirring on the measurement of integrated ultrasonic level gauges

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When an integrated ultrasonic level gauge transducer emits ultrasonic pulses, it has a certain emission angle. There must be no obstacles in the area radiated by the emitted ultrasonic beam, from the lower edge of the transducer to the surface of the medium being tested. Therefore, when installing the device, it is necessary to avoid equipment inside the tank as much as possible, such as ladders, heating equipment, and limit switch brackets. In this case, it is necessary to perform “pseudo-echography*” during device installation. It should also be noted that the ultrasonic beam must not intersect with the material feed stream. During installation, also note: the high material level must not enter the measurement blind area ； It is necessary to maintain a certain distance from the tank wall ； Perhaps it is to keep the transducer perpendicular to the liquid surface ； When installed in hazardous areas, it is necessary to comply with the **rules for devices in explosive environments**; in locations where explosion protection is required, ultrasonic level gauges must be grounded. When the medium has good reflectivity, the receiver diameter of the container is large, and the receiving length can be slightly longer than the recommended values for receiving lengths with different diameters listed in the table on the right side of the converter. The end of the reception at this moment needs to be smooth and free of burrs, as rounded as possible. Otherwise, it is necessary to conduct “pseudo-echography*”. When the reflectivity of the medium is poor, or when the material level is high and may enter a blind area, it is necessary to raise the receiving position; in such cases, a horn-shaped waveguide device can be used to increase the directivity of the signal, thereby reducing the impact of reception on the measurements. 　　1. When there is stirring in the tank, the integrated ultrasonic level gauge should be placed away from the stirrer; after the gauge is installed, \"pseudo-echo technology*\" should be applied while stirring is in progress in order to eliminate the influence of pseudo-echoes generated by the stirrer blades. If foam is generated or waves are created due to stirring, the wave guide device method should be used. 　　2. During feeding, stirring, or other processing activities inside the container, foam may form on the surface of certain media, which attenuates the signal from the ultrasonic level gauge. In the case of foam formation errors, the sensor device should be placed inside a waveguide or a waveguide radar level gauge should be used. Guided wave radar level gauges are not affected by foam, making them the choice for such applications. 　　3. If there is strong airflow inside the container, and the integrated ultrasonic level gauge is installed outdoors in windy conditions, or if there are air vortices inside the container, the sensor unit should be placed inside a wave guide, or a guided-wave radar level gauge should be used.