Search

CN-122014681-A - Inner flow jet cooling device and cooling method of centrifugal compressor

CN122014681ACN 122014681 ACN122014681 ACN 122014681ACN-122014681-A

Abstract

The invention discloses an inner flow jet cooling device and a cooling method of a centrifugal compressor, which solve the problems that the prior art cannot directly restrain temperature rise in real time in the compression process so as to solve the problem of fundamental overtemperature, or the problems of equipment damage, efficiency reduction and limited applicability are accompanied when cooling is introduced. The cooling point is arranged at the middle part of the flow passage inside the centrifugal impeller, and the main flow working medium is partially compressed and has enough superheat degree at the position, so that the injected refrigerant can be immediately evaporated and absorbed, and the compression heat is directly taken away, thereby effectively reducing the erosion and abrasion of liquid drops to blade materials, obviously prolonging the service life of the impeller, reducing the impact and disturbance to the main flow state, being beneficial to maintaining the stability of a flow field, reducing the pneumatic loss and improving the efficiency of the compressor.

Inventors

  • GONG XIXIAN
  • XU HUANCHAO
  • GUO CONG
  • JIANG YUYAN
  • ZHAO JIANZHONG

Assignees

  • 青岛国能永泰智能装备有限公司

Dates

Publication Date
20260512
Application Date
20260211

Claims (8)

  1. 1. An in-flow jet cooling device for a centrifugal compressor, comprising: A centrifugal impeller (202), the back of which and the blades (201) form a main flow working medium channel; a rotation shaft (301) fixedly connected to the centrifugal impeller (202) in a coaxial manner; The refrigerant injection unit comprises a static refrigerant inlet pipe (101) and an injection pipe (102) and is used for guiding the refrigerant into the rotating part; a storage chamber (103) arranged inside the rotating shaft (301) and/or the hub of the centrifugal impeller (202), in fluid communication with the injection tube (102), for containing a refrigerant; an apertured chuck (105) provided at the front end or inside the centrifugal impeller (202); at least one outflow hole (104) arranged on the perforated chuck (105) and used for communicating the storage cavity (103) with the main flow working medium channel; When the rotating shaft (301) drives the centrifugal impeller (202) to rotate, the refrigerant is sprayed into the main flow working medium from the storage cavity (103) through the outflow hole (104) under the action of centrifugal force, so that the cooling is realized while the compression is performed.
  2. 2. The centrifugal compressor inner stream jet cooling device according to claim 1, wherein the aperture of the outflow hole (104) is 1 mm or less.
  3. 3. The centrifugal compressor inner flow jet cooling device according to claim 1 or 2, wherein a porous structure for uniform distribution of refrigerant is provided in the storage chamber (103).
  4. 4. The centrifugal compressor inner flow jet cooling device according to claim 1 or 2, wherein the outlet structure of the outflow hole (104) is a bell mouth, a porous structure or is sprayed with a porous coating to promote uniform mixing of the refrigerant and the main flow working medium.
  5. 5. Centrifugal compressor inner flow jet cooling device according to claim 1 or 2, characterized in that the channel direction of the outflow holes (104) is axially or counter-circumferentially inclined to reduce interference with the main flow.
  6. 6. A centrifugal compressor comprising the centrifugal compressor inner stream injection cooling device according to any one of claims 1 to 5.
  7. 7. A method of centrifugal compressor in-flow jet cooling, applied to the apparatus of any one of claims 1 to 5, comprising the steps of: a storage chamber (103) for introducing the refrigerant into the high-speed rotating member through the stationary refrigerant injection unit; The centrifugal force generated by the high-speed rotation of the rotating part is utilized to drive the refrigerant in the storage cavity (103) to be sprayed out from the outflow hole (104) positioned at the middle section of the main flow working medium channel; the ejected refrigerant and the main stream working medium being compressed are directly mixed in the centrifugal impeller channel to absorb compression heat, so that the working medium is compressed and cooled.
  8. 8. The method of cooling by internal flow injection of a centrifugal compressor according to claim 7, wherein said refrigerant is a liquid working medium.

Description

Inner flow jet cooling device and cooling method of centrifugal compressor Technical Field The invention relates to the technical field of centrifugal compressors, in particular to an inner flow jet cooling device and a cooling method of a centrifugal compressor. Background Centrifugal compressors are key power equipment widely applied in the industrial field and are commonly used in occasions such as air compression, refrigeration cycle, high-temperature heat pump, process gas pressurization and the like. The working principle determines that the working medium is accompanied by significant temperature rise in the compression process, which phenomenon becomes particularly prominent in applications where high compression ratios or high exhaust temperatures are sought. Excessive temperature not only increases compression power consumption and reduces energy efficiency of a system, but also threatens safe operation of equipment, for example, the rotating parts such as impellers and the like fail due to the reduction of material strength, or decomposition and degradation of organic working media and lubricating oil are caused. Therefore, the effective cooling of working media in the compression process is a key technical requirement for ensuring the efficient, reliable and long-service-life operation of the centrifugal compressor. To cope with the above problems, the prior art mainly adopts the following two cooling modes: First, pre-cooling and interstage cooling. The heat exchanger is arranged at the air inlet of the compressor or between stages of multi-stage compression to cool the working medium. This approach, while capable of reducing the intake air temperature or inter-stage temperature, is essentially a "cool before compress" or "compress, cool, recompress" serial flow. The cooling action of the compressor takes place outside or after the compression stage, and the compression thermodynamic process inside the impeller cannot be directly interfered with. When the single-stage compression ratio is extremely large or the working temperature area is extremely high, the temperature of the working medium in the impeller and the runner can still rise to dangerous level, and the overtemperature risk cannot be eradicated. In addition, the additional heat exchanger can introduce additional flow resistance, so that pressure loss is caused, the total pressure recovery coefficient of the system is strictly required, and partial energy saving benefits can be offset. And secondly, spray cooling of the inlet air. It is common in the field of gas turbine air intake and the like to reduce the temperature of the air intake by spraying atomized droplets into the air intake pipeline and utilizing the evaporation and heat absorption of the atomized droplets. However, this approach has significant limitations in that, first, there are severe restrictions on the size of the spray, evaporation distance, and air humidity, and the cooling capacity and range of application are limited to prevent unvaporised droplets from striking and eroding the downstream high-speed rotating impeller. Secondly, for many compressor applications, the inlet working fluid is already near saturation, and excessive spray can lead to premature liquid phase, possibly causing liquid impact, and jeopardizing the compressor safety. More importantly, the nozzle of the traditional spraying device is fixed on the static shell, and huge relative speed exists between sprayed liquid drops and the impeller rotating at high speed, so that severe impact erosion of the liquid drops to the impeller is caused, the service life of the impeller is seriously shortened, the uniformity and stability of main air inlet flow are seriously disturbed, extra pneumatic loss is brought, and the efficiency and the operation stability of the compressor are influenced. Disclosure of Invention The invention aims to provide an inner flow jet cooling device and a cooling method of a centrifugal compressor, which are used for solving the problems that the prior art cannot directly restrain temperature rise in real time in the compression process to solve the problem of basic overtemperature or equipment damage, efficiency reduction, limited applicability and the like are associated when cooling is introduced. In order to achieve the above purpose, the invention provides a technical scheme that an inner flow jet cooling device of a centrifugal compressor comprises: The centrifugal impeller, the back of which and the blades form a main flow working medium channel; The rotating shaft is coaxially and fixedly connected with the centrifugal impeller; The refrigerant injection unit comprises a static refrigerant inlet pipe and an injection pipe and is used for guiding the refrigerant into the rotating part; the storage cavity is arranged in the rotating shaft and/or the hub of the centrifugal impeller, is in fluid communication with the injection pipe and is used for accommodating a refrigera