Smart accumulator with oil circulation ratio sensing

An accumulator for a vapor compression cycle system comprising:

• a shell defining an internal cavity;
• an inlet line to the internal cavity proximate to a top end of the shell, the inlet line configured to eject vapor and oil into the internal cavity;
• an outlet line having a vapor inlet proximate to the top end, an oil inlet proximate to the bottom end, and an outlet that extends out of the internal cavity of the shell;
• a valve;
• an upper level switch;
• and a lower level switch,
• wherein the valve is configured open and cause to flow into the outlet line when oil is at the upper level switch and the valve is configured to close when oil reaches the lower level switch, and
• wherein the accumulator further includes a shroud disposed inside of the accumulator wherein the inlet line comprises at least one perforation configured to direct oil and vapor onto the shroud.

A system, comprising:

• an accumulator connected to a suction line of a vapor compression cycle system, the accumulator comprising a sensor configured to detect the level of oil and a valve, wherein the valve opens when oil is at a high-level and closes when oil is at a low-level;
• a processor configured to
• measure a mass flow rate of oil in the vapor compression cycle system based on an amount of time taken to fill a portion of the accumulator,
• determine an oil circulation ratio based on the measured time taken to fill the portion of the accumulator;
• and
• output the oil circulation ratio.

A method comprising:

• accumulating oil in an accumulator attached to a suction line of a vapor compression cycle system,
• determining a mass flow rate of oil based on time taken to fill a volume in the accumulator;
• determining a mass flow rate of liquid refrigerant and oil in the vapor compression cycle system;
• calculate an oil circulation ratio based on mass flow rate of oil and the mass flow rate of liquid refrigerant and oil;
• and
• output the oil circulation ratio.