In air conditioning and refrigeration systems a small
amount of oil is carried along with the refrigerant and is
retained in the system components. Oil retention
characteristics in the condenser, evaporator, liquid and suction
lines were studied and are presented and discussed here.
Refrigerant R22 with miscible lubricant was considered to
investigate oil retention physics in the widest possible range of
transport properties. A parametric analysis was performed in
the suction line and it showed that oil retention depends on the
oil mass fraction, vapor refrigerant mass flux, mixture
viscosity ratio and orientation of the pipe. Computational
method and correlations were used with the input data gotten
from a 10KW rated compressor with five passes of inlet and
outlet cross flow. In the evaporator and condenser, Premoli’s
and Chisholm’s correlated void fraction s were used. In
the suction line, an increase in mixture viscosity of about 55%
caused a rise in oil retention in the range of 50%, depending on
the oil mass fraction. Oil retention in the upward vertical
suction line is about 50% higher than in the horizontal line at
similar conditions. Results agreed with other published works
in the same subject.

How to Cite
EKE, G. B.; OKPARA, K. P.. Investigation of Oil Retention in Vapor Ompression Systems: A Case Study. Global Journal of Research In Engineering, [S.l.], v. 10, n. 7, dec. 2010. ISSN 2249-4596. Available at: <https://engineeringresearch.org/index.php/GJRE/article/view/112>. Date accessed: 25 jan. 2022.