Simultaneous vapor and liquid injection
Systems and methods for simultaneous vapor and liquid injection for a transport climate control system are provided. The system includes a compressor, a condenser having a condensing unit and a sub-cooling unit, a receiver, an economizer having a vapor outlet and a liquid outlet, a controller, and a flow control device. The receiver is disposed downstream of the condensing unit and upstream of the sub-cooling unit. The economizer is disposed downstream of the sub-cooling unit. The compressor includes a suction port, a vapor injection port connected to the vapor outlet of the economizer, and a liquid injection port separated from the vapor injection port. The controller is configured to control the flow control device to adjust an amount of liquid refrigerant into the liquid injection port to maintain a discharge temperature of the compressor at or below a threshold.
1 . A transport climate control system with simultaneous vapor and liquid injection, comprising:
a compressor, a condenser, a sub-cooler, a receiver, an economizer having a vapor outlet and a liquid outlet, a controller, and a flow control device,
wherein the receiver is disposed downstream of the condenser and upstream of the sub-cooler, the economizer is disposed downstream of the sub-cooler,
the compressor includes a suction port, a vapor injection port connected to the vapor outlet of the economizer, and a liquid injection port separated from the vapor injection port,
the controller is configured to control the flow control device to adjust an amount of liquid refrigerant into the liquid injection port to maintain a discharge temperature of the compressor at or below a threshold,
the liquid injection port is connected to the liquid outlet of the economizer and is connected to an outlet of the sub-cooler at a location upstream of the economizer, and
the flow control device is disposed directly downstream of the liquid outlet of the economizer, directly downstream of the outlet of the sub-cooler, and directly upstream of the compressor.
2 . The system according to claim 1 , wherein the liquid injection port is disposed closer to a discharge port of the compressor than the vapor injection port.
3 . The system according to claim 1 , wherein the vapor injection port is separated from the suction port.
4 . The system according to claim 1 , wherein the liquid injection port is connected to an outlet of the receiver at a location upstream of the sub-cooler, the flow control device is disposed downstream of the outlet of the receiver and upstream of the compressor.
5 . The system according to claim 1 , further comprising an oil separator disposed downstream of the compressor and upstream of the condenser.
6 . The system according to claim 5 , wherein the oil separator includes a liquid outlet and a vapor outlet, the liquid outlet of the oil separator is connected to the liquid injection port at a location downstream of the flow control device.
7 . The system according to claim 5 , wherein the oil separator includes a liquid outlet and a vapor outlet, the liquid outlet of the oil separator is connected to the compressor at a location separate from the liquid injection port and the vapor injection port.
8 . A transport climate control system with simultaneous vapor and liquid injection, comprising:
a compressor, a condenser, a sub-cooler, a receiver, an economizer having a vapor outlet and a liquid outlet, a controller, and a flow control device,
wherein the receiver is disposed downstream of the condenser and upstream of the sub-cooler, the economizer is disposed downstream of the sub-cooler,
the compressor includes a suction port, a vapor injection port connected to the vapor outlet of the economizer, and a liquid injection port separated from the vapor injection port,
the controller is configured to control the flow control device to adjust an amount of liquid refrigerant into the liquid injection port to maintain a discharge temperature of the compressor at or below a threshold,
the liquid injection port is connected to the liquid outlet of the economizer and is connected to an outlet of the receiver at a location upstream of the sub-cooler, and
the flow control device is disposed directly downstream of the liquid outlet of the economizer, directly downstream of the outlet of the receiver, and directly upstream of the compressor.
9 . A transport climate control system with simultaneous vapor and liquid injection, comprising:
a compressor, a condenser, a sub-cooler, a receiver, an economizer having a vapor outlet and a liquid outlet, a controller, and a flow control device,
wherein the receiver is disposed downstream of the condenser and upstream of the sub-cooler, the economizer is disposed downstream of the sub-cooler,
the compressor includes a suction port, a vapor injection port connected to the vapor outlet of the economizer, and a liquid injection port separated from the vapor injection port,
the controller is configured to control the flow control device to adjust an amount of liquid refrigerant into the liquid injection port to maintain a discharge temperature of the compressor at or below a threshold,
the liquid injection port is connected to the liquid outlet of the economizer, is connected to an outlet of the sub-cooler at a location upstream of the economizer, and is connected to an outlet of the receiver at a location upstream of the sub-cooler, and
the flow control device is disposed directly downstream of the liquid outlet of the economizer, directly downstream of the outlet of the sub-cooler, directly downstream of the outlet of the receiver, and directly upstream of the compressor.