Abstract: Provided are a magnetic bearing compressor, an air conditioner and a protective air gap value setting method. The magnetic bearing compressor includes: a rotor, a magnetic bearing, a sensor, and a control device. The magnetic bearing is sleeved on the rotor; the sensor is arranged on the magnetic bearing and is configured to detect a distance value between the rotor and the sensor on a preset plane; the control device is configured to receive the distance value and determine the minimum distance value and the maximum distance value between the rotor and the magnetic bearing according to the distance value, and obtain an absolute value of a difference of the maximum distance value and the minimum distance value; and the control device obtains a protective air gap value according to the absolute value and a preset protection coefficient when the absolute value is less than or equal to a preset air gap value.

Abstract: An engine and a double-swirl mixing device thereof are provided. The double-swirl mixing device includes a mixing tube configured to mix exhaust gas with urea, a tapered mixer including a tapered tube having an outlet end extending into the mixing tube, and a plurality of tapered swirl plates which are arranged along a circumferential direction on a side wall of the tapered tube, and a fan-type blade arranged at the outlet end of the tapered tube, and a diameter of an inlet end of the tapered tube is smaller than a diameter of the outlet end of the tapered tube.

Abstract: Provided are a magnetic bearing compressor, an air conditioner and a protective air gap value setting method. The magnetic bearing compressor includes: a rotor, a magnetic bearing, a sensor, and a control device. The magnetic bearing is sleeved on the rotor; the sensor is arranged on the magnetic bearing and is configured to detect a distance value between the rotor and the sensor on a preset plane; the control device is configured to receive the distance value and determine the minimum distance value and the maximum distance value between the rotor and the magnetic bearing according to the distance value, and obtain an absolute value of a difference of the maximum distance value and the minimum distance value; and the control device obtains a protective air gap value according to the absolute value and a preset protection coefficient when the absolute value is less than or equal to a preset air gap value.

Abstract: An engine and a double-swirl mixing device thereof are provided. The double-swirl mixing device includes a mixing tube configured to mix exhaust gas with urea, a tapered mixer including a tapered tube having an outlet end extending into the mixing tube, and a plurality of tapered swirl plates which are arranged along a circumferential direction on a side wall of the tapered tube, and a fan-type blade arranged at the outlet end of the tapered tube, and a diameter of an inlet end of the tapered tube is smaller than a diameter of the outlet end of the tapered tube.

Abstract: Provided in the invention is an SCR system urea mixer. The SCR system urea mixer comprises an outer pipe and an inner pipe arranged in the outer pipe. The outer pipe comprises an air inlet cone pipe (11) and an air inlet straight pipe (12) connected with the air inlet cone pipe (11). The inner pipe comprises an air inlet rectifying pipe (21) and a porous pipe (22). The porous pipe (22) is sleeved outside the air inlet rectifying pipe (21). The air inlet rectifying pipe (21) is provided with an airstream rotating mechanism (211), and the airstream rotating mechanism (211) is used for rotating exhaust gas which enters into the air inlet cone pipe (11). A rotating structure and a porous structure are used in the SCR system urea mixer, so that urea and engine exhaust are fully mixed; and the SCR system urea mixer is provided with heat preservation measures to prevent the crystallization of the urea.