An air-temperature conditioning system includes a frost resistant heat exchanger that has an exterior heat transfer surface covered by a hydrophobic coating. An anti-frost device of the air-temperature conditioning system is constructed and arranged to mitigate frost accumulation on the heat exchanger by leveraging characteristics of the hydrophobic coating.

The present invention relates to a pump (15) for pumping a coolant (9) within a Dewar vessel (1) and to a corresponding Dewar vessel (1) for storing samples in a coolant (9). The Dewar vessel (1) comprises a thermally insulated reservoir (3) for the coolant (9) and a sample vessel (11) provided separately and arranged in the thermally insulated reservoir (3). The reservoir (3) is connected to the sample vessel (11) in such a way that the level of coolant (9) is constant in the sample vessel (11). Pump (15) may help in keeping the level of coolant (9) in the sample vessel (11) constant. For this purpose the pump (15) comprises a chamber (17) with an inlet (19) and an outlet (21), a closing element (23) and a pressure increasing device (25). Therein, the inlet (19) is connectable to the reservoir (3) and the outlet (21) is connectable to a sample vessel (11) of the Dewar vessel (1). The chamber (17) is adapted to fill with coolant (9) through the inlet (19) by gravity and the closing element (23) is adapted to automatically close the chamber (17) when it is full of coolant (9). The pressure increasing device (25) is adapted to increase the pressure within the chamber (17), after the chamber (17) is closed, until the coolant (9) is released through the outlet (21).

This disclosure provides a heat exchanger that can more efficiently remove the frost attached to the heat exchanger. A configuration of a heat exchanger according to the present invention includes a heat transfer member (e.g., a fin) that performs heat exchange with air, wherein the heat transfer member (e.g., the fin) includes, in a vicinity of an upstream-side edge in an air traveling direction, a plurality of linear protruding portions that are formed in parallel to the edge.

A method of reducing a temperature of at least one item including: transporting the at least one item on a moving substrate within an enclosure, the enclosure including at least one impingement apparatus; providing a coolant to at least one of a high pressure zone or a low pressure zone of the enclosure; circulating the coolant through the high and low pressure zones using a variable-speed gas circulation device of the impingement apparatus; directing impingement jets through openings in at least one impinger of the impingement apparatus toward the moving substrate disposed within the low pressure zone; and intermittently performing an operation on the at least one impingement apparatus during said transporting including: (i) reducing a speed of the variable-speed gas circulation device; (ii) vibrating the at least one impinger; and (iii) increasing the speed of the variable-speed gas circulation device.

An impingement apparatus associated with a conveyor includes: (a) a shell supporting an impinger; and (b) a coolant delivery apparatus enclosed by the shell, the coolant delivery apparatus including a gas circulation device for directing a coolant to the impinger; the impinger including: (i) an impingement plate including openings for directing impingement jets toward the conveyor; (ii) at least one non-circular cam in mechanical communication with the at least one conveyor and rotatable when the conveyor is in motion; and (iii) at least one connector in mechanical communication with the at least one cam and the impingement plate, the connector displaceable during rotation of the at least one cam to elevate and lower the impingement plate.

A vapor compression heat transfer system includes an evaporator assembly, an ice-prone surface, and an ultrasonic energy source. The ultrasonic energy source when energized vibrating the ice-prone surface at a frequency of from 30 kHz to 60 kHz. The ultrasonic energy source can be a piezoelectric transducer. The piezoelectric transducer can be operated in an ice sensing mode and a deicing mode and can also verify the removal of ice. A method of conducting one of heating, ventilation, air conditioning and refrigeration (HVACR) is also disclosed.

A refrigerating device used to reduce a temperature of drinks is provided and a higher refrigerating efficiency can be obtained through a control method and a control system thereof. The refrigerating device includes a pre-refrigeration unit used to pre-refrigerate a raw material; a main-refrigeration unit in communication with the pre-refrigeration unit and used to accommodate the pre-refrigerated raw material and refrigerate the raw material further; a dispenser in communication with the main-refrigeration unit and used to dispense the frozen drink in the main-refrigeration unit; and a refrigeration system providing a refrigerating capacity to the pre-refrigeration unit and the main-refrigeration unit.

The present disclosure discloses a defrosting device, including a heating unit provided at a lower side of an evaporator, and configured to heat working fluid therein; and a plurality of heat pipes, both end portions of which are connected to an inlet and an outlet of the heating unit, respectively, and at least part of which are disposed adjacent to a cooling tube of the evaporator to emit heat to the cooling tube due to high temperature working fluid heated and transferred by the heating unit, wherein the plurality of heat pipes are configured with a first heat pipe and a second heat pipe disposed to form two rows on a front portion and a rear portion of the evaporator, respectively, and the first heat pipe and the second heat pipe are formed in different lengths.