Conditioning system including vapor compression system and humidity control system
A conditioning system includes a vapor compression system and a humidity control system. The vapor compression system includes an evaporator, a condenser, a first fan that produces a first airflow across the evaporator toward a conditioned interior space, and a second fan that produces a second airflow from the condenser toward an exterior space. The humidity control system includes a first mass exchange device positioned in the first airflow, a second mass exchange device positioned in the second airflow, and a heat exchanger in fluid communication with both mass exchange devices. The heat exchanger includes a first path and a second path that are thermally coupled and that provide liquid desiccant between the first and second mass exchange devices. The first and second mass exchange devices each include a plurality of cavities configured to permit liquid desiccant to flow therethrough.
1 . A conditioning system comprising:
a vapor compression system including:
an evaporator,
a condenser,
a first fan for producing a first airflow across the evaporator toward a conditioned interior space, and
a second fan for producing a second airflow from the condenser toward an exterior space; and
a humidity control system including:
a first mass exchange device positioned in the first airflow downstream from the evaporator, the first mass exchange device including a plurality of first cavities each configured to permit a flow of a liquid desiccant from an inlet of the first mass exchange device to an outlet of the first mass exchange device, wherein each first cavity of the first mass exchange device has a U-shaped cross section from the inlet to the outlet perpendicular to a direction of the flow of fluid desiccant, wherein the U-shaped cross section defines an open portion exposed to the first airflow, and the open portion of each first cavity is covered by a first vapor permeable membrane,
a second mass exchange device positioned in the second airflow downstream from the condenser, the second mass exchange device including a plurality of second cavities each configured to permit a flow of the liquid desiccant from an inlet of the second mass exchange device to an outlet of the second mass exchange device, wherein each second cavity of the second mass exchange device has a U-shaped cross section from the inlet to the outlet perpendicular to a direction of the flow of fluid desiccant, wherein the U-shaped cross section defines an open portion exposed to the second airflow, and the open portion of each second cavity is covered by a second vapor permeable membrane, and
a liquid desiccant heat exchanger coupled in fluid communication with the first mass exchange device and the second mass exchange device, the liquid desiccant heat exchanger including a first path for providing liquid desiccant in a first direction from the first mass exchange device to the second mass exchange device, and a second path adjacent the first path for providing liquid desiccant in a second direction from the second mass exchange device to the first mass exchange device, wherein the first path is thermally coupled to the second path.
2 . The conditioning system of claim 1 , wherein the first mass exchange device includes an inlet and an outlet, the second mass exchange device includes an inlet and an outlet, the first path is in fluid communication with the outlet of the first mass exchange device and the inlet of the second mass exchange device, the second path is in fluid communication with the outlet of the second mass exchange device and the inlet of the first mass exchange device.
3 . The conditioning system of claim 1 , wherein the humidity control system further comprises a first liquid desiccant tank configured for holding liquid desiccant, and a second liquid desiccant tank configured for holding liquid desiccant, wherein the first liquid desiccant tank is in fluid communication with the first mass exchange device and the second liquid desiccant tank is in fluid communication with the second mass exchange device.
4 . The conditioning system of claim 3 , wherein the first liquid desiccant tank is integral with the first mass exchange device and the second liquid desiccant tank is integral with the second mass exchange device.
5 . The conditioning system of claim 4 , wherein the first liquid desiccant tank is located between the liquid desiccant heat exchanger and the first mass exchange device to receive liquid desiccant from the liquid desiccant heat exchanger and provide liquid desiccant to the first mass exchange device, and the second liquid desiccant tank is located between the liquid desiccant heat exchanger and the second mass exchange device to receive liquid desiccant from the liquid desiccant heat exchanger and provide liquid desiccant to the second mass exchange device.
6 . The conditioning system of claim 4 , wherein the humidity control system further comprises at least one pump configured to circulate liquid desiccant between the first mass exchange device, the liquid desiccant heat exchanger, and the second mass exchange device.
7 . The conditioning system of claim 1 , wherein the first direction and the second direction are opposite parallel directions.
8 . The conditioning system of claim 1 , further comprising a controller, the controller programmed to operate the vapor compression system to control a temperature in the conditioned interior space to a temperature setpoint, and to operate the humidity control system in conjunction with the vapor compression system to control a humidity in the conditioned interior space to a humidity setpoint.
9 . The conditioning system of claim 1 , wherein the humidity control system does not include a connection to receive water from an external water source.
10 . A humidity control system for use in a vapor compression system including an evaporator and a condenser, the humidity control system comprising:
a first mass exchange device configured to be positioned in a first airflow downstream from the evaporator and upstream from a conditioned interior space, the first mass exchange device including at least one first cavity configured to permit a flow of a liquid desiccant from an inlet of the first mass exchange device to an outlet of the first mass exchange device, wherein each first cavity of the first mass exchange device has a U-shaped cross section from the inlet to the outlet perpendicular to a direction of the flow of fluid desiccant, wherein the U-shaped cross section defines an open portion exposed to the first airflow, and the open portion of each first cavity is covered by a first vapor permeable membrane;
a second mass exchange device configured to be positioned in a second airflow downstream from the condenser and upstream from an exterior space, the second mass exchange device including at least one second cavity configured to permit a flow of the liquid desiccant from an inlet of the second mass exchange device to an outlet of the second mass exchange device, wherein each second cavity of the second mass exchange device has a U-shaped cross section from the inlet to the outlet perpendicular to a direction of the flow of fluid desiccant, wherein the U-shaped cross section defines an open portion exposed to the second airflow, and the open portion of each second cavity is covered by a second vapor permeable membrane; and
a liquid desiccant heat exchanger coupled in fluid communication with the first mass exchange device and the second mass exchange device, the liquid desiccant heat exchanger including a first path for providing liquid desiccant in a first direction from the first mass exchange device to the second mass exchange device, and a second path adjacent the first path for providing liquid desiccant in a second direction from the second mass exchange device to the first mass exchange device, wherein the first path is thermally coupled to the second path.
11 . The humidity control system of claim 10 , wherein the first mass exchange device includes an inlet and an outlet, the second mass exchange device includes an inlet and an outlet, the first path is in fluid communication with the outlet of the first mass exchange device and the inlet of the second mass exchange device, and the second path is in fluid communication with the outlet of the second mass exchange device and the inlet of the first mass exchange device.
12 . The humidity control system of claim 10 , further comprising a first liquid desiccant tank configured for holding liquid desiccant, and a second liquid desiccant tank configured for holding liquid desiccant, wherein the first liquid desiccant tank is in fluid communication with the first mass exchange device and the second liquid desiccant tank is in fluid communication with the second mass exchange device.
13 . The humidity control system of claim 12 , wherein the first liquid desiccant tank is integral with the first mass exchange device and the second liquid desiccant tank is integral with the second mass exchange device.
14 . The humidity control system of claim 12 , wherein the first liquid desiccant tank is located between the liquid desiccant heat exchanger and the first mass exchange device to receive liquid desiccant from the liquid desiccant heat exchanger and provide liquid desiccant to the first mass exchange device, and the second liquid desiccant tank is located between the liquid desiccant heat exchanger and the second mass exchange device to receive liquid desiccant from the liquid desiccant heat exchanger and provide liquid desiccant to the second mass exchange device.
15 . The humidity control system of claim 10 , further comprising at least one pump configured to circulate liquid desiccant between the first mass exchange device, the liquid desiccant heat exchanger, and the second mass exchange device.
16 . The humidity control system of claim 10 , wherein the first direction and the second direction are opposite parallel directions.
17 . The humidity control system of claim 10 , wherein the humidity control system does not include a connection to receive water from an external water source.
18 . The humidity control system of claim 10 , further comprising a controller, the controller programmed to operate the humidity control system in conjunction with the vapor compression system to control a humidity in the conditioned interior space to a humidity setpoint.
19 . The conditioning system of claim 1 , wherein the system is configured such that liquid desiccant in each first cavity of the first mass exchange device flows in a direction opposite to a direction of the first airflow, and liquid desiccant in each second cavity of the second mass exchange device flows in a direction parallel to a direction of the second airflow.
20 . The humidity control system of claim 10 , wherein the system is configured such that liquid desiccant in each first cavity of the first mass exchange device flows in a direction opposite to a direction of the first airflow, and liquid desiccant in each second cavity of the second mass exchange device flows in a direction parallel to a direction of the second airflow.