Share

Estimation of oil circulation ratio in a vapor compression system using a discharge side oil separator.

Number: 2208

Author(s) : HAIDER S. A., SEETON C., MILJKOVIC N., ELBEL S.

Summary

For vapor compression systems, the standard method for measuring the oil circulation ratio (𝑂𝐢𝑅) is via sampling, as described in the ASHRAE standard 41.4. Sampling is tedious, alters the steady state of the system and can depend on several factors such as refrigerant-oil miscibility and sampling cylinder orientation. Many compressor manufacturers conduct compressor performance tests which rely on hot gas cycles that do not have a liquid line for sampling. They mount oil separators at the compressor discharge to separate the oil flow from the refrigerant flow and use the mass flow rates to estimate real-time 𝑂𝐢𝑅. In a real case, some oil will always escape with the separated refrigerant, and some refrigerant, dissolved in oil, will always escape with the separated oil, significantly reducing the accuracy of the procedure. The present study investigates 𝑂𝐢𝑅 measurements using an oil separator-based approach for a full vapor compression cycle working with R134a and PAG ISO 46 oil. A full cycle allows sampling to also be performed in parallel for validation. Solubility corrections were performed to account for the refrigerant dissolved in the oil returning to the compressor suction. It was found that the 𝑂𝐢𝑅 values from the oil separator-based approach, upon solubility correction, fell within 6% of the sampling results. Discissions were also made on the usefulness of the oil separator efficiency values at the oil and vapor outlet ports for the oil separator-based approach.

Available documents

Format PDF

Pages: 10 p.

Available

Free

Download

Details

  • Original title: Estimation of oil circulation ratio in a vapor compression system using a discharge side oil separator.
  • Record ID : 30033083
  • Languages: English
  • Subject: Technology
  • Source: 2024 Purdue Conferences. 20th International Refrigeration and Air-Conditioning Conference at Purdue.
  • Publication date: 2024/07/17

Links


See other articles from the proceedings (187)
See the conference proceedings

Indexing