Share

Source identification and in situ quantification of oil refrigerant mist generation by discharge valve opening process.

Number: pap. 1563

Author(s) : ZIMMERMANN A. J. P., HRNJAK P. S.

Summary

Oil in circulation in refrigeration systems generally degrades their thermodynamic and reliability performance. The vast majority of compressors used in the residential, automotive and light commercial air conditioning and refrigeration use pressure actuated reeds as the discharge valves. These valves are the gateway for the oil to leave the compressor to the rest of the system. In this work, a residential AC scroll compressor was equipped with sight windows on the discharge plenum and visualization studies were carried out using high speed imaging and processing techniques to identify the moment of oil mist generation, and also provide quantification of the droplet size and velocity distributions inside the discharge plenums. The compressor was run in a full system setup with measuring devices for mass flow rate, pressure, temperature and OCR (by sampling according to ASHRAE Standard 41.4). Oil viscosity was varied from 32cSt to 120cSt along with compressor volumetric flow rate (through operating frequency), all while using R134a as the refrigerant. It was found that a very fine mist (drops with diameters below 114 micrometers) is generated right at the start of the opening process of the valve followed by interaction between the vapor flow and liquid (oil-refrigerant mixture) flow with the internal geometric features of the discharge plenum to generate larger droplets. It was observed that at higher volumetric flow rates, smaller droplets are produced and that the more viscous the oil, the larger the droplets generated, however this effect was not significant. In the discharge plenum, smaller droplets were identified and quantified.

Available documents

Format PDF

Pages: 10 p.

Available

  • Public price

    20 €

  • Member price*

    15 €

* Best rate depending on membership category (see the detailed benefits of individual and corporate memberships).

Details

  • Original title: Source identification and in situ quantification of oil refrigerant mist generation by discharge valve opening process.
  • Record ID : 30013987
  • Languages: English
  • Source: 2014 Purdue Conferences. 22nd International Compressor Engineering Conference at Purdue.
  • Publication date: 2014/07/14

Links


See other articles from the proceedings (138)
See the conference proceedings

Indexing