Frost control for space conditioning
AssigneeInstitute of Gas Technology
InventorsRobert A. Macriss, Jaroslav Wurm, Vincent M. Huang
Life of this patent
Estimating the term…
Abstract
An apparatus and process for frost control for the ambient air heat exchanger of a space conditioning apparatus. The ambient air heat exchanger is immersed in a fluidized bed enhancing the heat transfer and physically reducing frost formation. In a preferred embodiment, the fluidized bed is supported by a support bed of non-fluidized solid particles. In one of the embodiments the particulate beds may be desiccant materials. The space conditioning apparatus and method of frost control of this invention permits smaller ambient air heat exchangers and accommodates greater transient conditions due to the enhanced heat transfer and physical prevention of ice formation resulting from the fluidized bed.
Claims37
In a freezer apparatus of the type having a refrigerant condenser exchanger to the exterior of the freezer closed space and a refrigerant evaporator exchanger inside the freezer closed space, the freezer operating at ambient air temperatures below about 0.degree. C. in the vicinity of said refrigerant evaporator exchanger of said freezer, the improvement comprising:
- substantially vertical duct means defining a confined passage for said ambient air;
- support means extending substantially across said passage;
- a plurality of fluidizable solid particles sufficient to form a shallow fluidizable bed supported on top of said support means within said confined passage;
- blower means capable of blowing said ambient air through said fluidizable bed at a fluidizing velocity thereby forming a shallow fluidized bed of said solid particles, said shallow fluidized bed having a fluidized depth of about 0.25 to about 2 inches;
- and
- said refrigerant evaporator with extended surface heat exchange means immersed in said shallow fluidizable bed and connected to said freezer refrigerant system to provide passage of said refrigerant of said freezer therethrough.
A method of frost control on a refrigerant evaporator exchanger inside a freezer closed space operating at ambient air temperatures below about 0.degree. C. comprising:
- passing said refrigerant of said freezer apparatus through said refrigerant evaporator exchanger having extended surface heat exchange means immersed in a shallow fluidizable bed supported by support means extending substantially across a substantially vertical duct;
- and
- passing said ambient air through said substantially vertical duct in thermal exchange relation to said refrigerant evaporator heat exchange means at sufficient velocity to fluidize said shallow bed to a fluidized depth of about 0.25 to about 2 inches thereby enhancing heat exchange between said refrigerant and said ambient air and reducing tendency of frost formation by physical vibration and abrasive action.
In a freezer apparatus of the type having a refrigerant condenser exchanger to the exterior of the freezer closed space and a refrigerant evaporator exchanger inside the freezer closed space, the freezer operating at ambient air temperatures below about 0.degree. C. in the vicinity of said refrigerant evaporator exchanger of said freezer, the improvement comprising:
- substantially vertical duct means defining a confined passage for said ambient air;
- support means extending substantially across said passage;
- a plurality of fluidizable solid dessicant particles comprising a fluidizable bed supported on top of said support means within said confined passage;
- blower means capable of blowing said ambient air through said fluidizable bed at a fluidizing velocity thereby forming a fluidized bed of said solid particles;
- and
- said refrigerant evaporator with extended surface heat exchange means immersed in said fluidizable bed and connected to said freezer refrigerant system to provide passage of said refrigerant of said freezer therethrough.
A method of frost control on a refrigerant evaporator exchanger inside a freezer closed space operating at ambient air temperatures below about 0.degree. C. comprising:
- passing said refrigerant of said freezer apparatus through said refrigerant evaportor exchanger having extended surface heat exchange means immersed in a fluidized bed of desiccant particles;
- and
- passing said ambient air in thermal exchange relation to said refrigerant evaporator heat exchange means at sufficient velocity to fluidize said bed thereby enhancing heat exchange between said refrigerant and said ambient air and reducing tendency of frost formation by physical vibration and abrasive action.
Dependencies are inferred from the claim text.