Patent Application
20190195518
The object of the invention is a device for manufacturing and storing ice, used in the cooling systems of industrial equipment, in room air conditioning, in food processing. Ice made from water using a compressor heat pump—in particular at the cost of cheaper electricity at night—it is stored in the device and then during the hours of using the cooling energy used in solid form or in the form of chilled water at a temperature of approximately 6° C., for example in a room air conditioning system.
The device for manufacturing and storing ice known and presented in a Japanese patent specification JPH 08261918 comprises a closed storage tank with thermally insulated walls, with embedded water reservoir having a plurality of separated inner chambers. The chambers are separated by heat exchange units with tubular exchangers, which are mounted horizontally and at intervals above each other. The exchangers of all heat exchange units are made of one tubular flow channel of low-boiling thermodynamic medium, bent in a meandering way at the level of each unit and the ends connected by vertically bent ends with plate heat exchange units adjacent above and below. At the level of each unit, straight sections of the flow channel are connected by a radiator plate. The flow channel of the heat exchange unit is included in the thermodynamic medium circuit of the compressor heat pump which comprises a compressor, a condenser, an expansion valve, an evaporator and the set of valves controlling the change of the flow direction of the thermodynamic medium. When setting the valves directing the flow of the medium to the device working in the thermodynamic circuit as an evaporator, the heat drawn from the water lowers its temperature below the freezing temperature and the water freezes on both sides of the flow channels and radiators of individual units, changing the physical state. After reaching the appropriate thickness of ice forming both on the upper and lower surface of the heat exchange units—by changing the electromagnetic valves built into the heat pump circuit—the flow direction of the thermodynamic medium changes. Compressed medium in the form of a gas at a temperature above 0° C. flows through the tubular channels of the device, with the effect of melting the ice on the surfaces of adhesion to the heat exchange units. Detached ice layers float upwards in the individual chambers, successively filling the chambers. In this device ice detachment is supported by the flow of water through the orifices in the radiator plate, located in parallel and in the immediate vicinity of the flow channels. The first layers of ice after detachment and floating upwards remain in the adhesion position to the lower surfaces of the radiator and flow channels—which causes a loss of energy for freezing and detaching the same layer of ice in subsequent cycles. Moreover, the thermodynamic transformation in the long flow channel of serially connected heat exchange units is locally inhomogeneous with the effect of diversification over the length of the channel. Additionally, the ice plates detaching from the bottom of the radiator remain at the place of detachment, which causes them to bond with each other during subsequent freezing cycles forming a block of ice, reducing or even preventing the efficient collection of the accumulated cooling energy.
In the device presented in the patent specification EP 0987502 tubular heat exchange units are immersed in the water reservoir in the inner chambers separated with vertical walls. Each unit has a flow channel shaped like a streamer in the vertical plane and is connected in parallel via the inlet collector and outlet collector to the thermodynamic medium circuit of the heat pump. The streamer of the flow channel in each unit is heat-welded through the vertical plate of the radiator, while the collectors are installed above the water reservoir. During the ice manufacturing phase, when the device is turned on in the evaporator function, icing in the form of ice plates occurs on both sides of the vertical surfaces of the heat exchange units, which cyclically, after reaching a certain thickness are detached by the heat of the medium, after changing the direction of the heat pump's circuit into the operation of the device in the condenser function. Ice plates after de-icing of the units flow up to reach a common level, where they contact the bulges accumulated at the flow channels—reducing the degree of ice filling of the usable capacity of the water reservoir. In addition, this way of arranging the ice plates makes the arrangement accidental. The detached ice plates under the influence of buoyancy tend to be able to bevel in the space between the evaporators, which reduces the degree of filling the tank with ice. Due to the irregular arrangement of the ice plates, the subsequent peel-off plates wedge with the previously detached ones and push out the evaporators which may lead to damage to the device at the next cycle.
In the devices for manufacturing and storing ice, the geometric similarity of the ice plates manufactured in all heat exchange units is important, which after detachment lifted off in the water bath adhere to each other with surfaces. The homogeneity of temperature conditions over the entire icing surface in all heat exchange units is crucial. In the solution of the harp exchanger as described of the specification US 20120292004—in order to ensure an even flow of the medium through all flow channels perpendicularly connected to the inlet collector and occurrence of phase transitions of similar intensity therein, affecting the local temperature of the flow channel—a tubular nozzle distributor was installed along the inlet collector. The distributor has nozzle orifices directed coaxially to the flow channels along the side. There is a gap between the nozzle orifices and the orifices of the flow channels in the wall of the inlet collector, in which the swirls of the streams are suppressed. It is important especially for the nozzles in the initial section. The nozzle orifices in the wall of the tubular nozzle distributor have diameters increasing successively from the supply end of the thermodynamic medium. In harp exchangers the phase transition of the thermodynamic medium starts at the inlet collector, passes through the flow channels and ends at the outlet collector-resulting in the temperature differential along the length of the flow channels.
The object of the present invention is to develop a device in which the manufacturing of ice and its storage will be carried out with the lowest possible amount of electric energy and the highest degree of ice filling of the geometric capacity of the water reservoir.
The device according to the invention partially uses the features of known solutions using a heat-insulated storage tank with a water reservoir embedded inside, wherein a plurality of inner chambers are separated by horizontally mounted and spaced apart units with tubular heat exchangers. The heat exchange units are incorporated in parallel in the thermodynamic medium circuit of the heat pump through the inlet collector and the outlet collector, in parallel position and connected through the perpendicular tubular flow channels and which are heat-welded together by the plate of the radiator. The tubular nozzle distributor is inserted longitudinally to the inside of the inlet collector. The device is incorporated in the heat pump circuit comprising the valve assembly controlling the flow direction of the thermodynamic medium.
The invention is distinguished by the particular design of the heat exchange unit. Each heat exchange unit consists of two identical heat exchangers incorporated in parallel in the heat pump circuit of the exchangers. The exchangers have the final sections of the flow channel connections to the outlet collector bent off the radiator plane, which determine straight sections of the flow channels coming out from the inlet collector. The deflection has a dimension greater than half the sum of the outside diameters of the inlet and outlet collectors, the heat exchangers being superimposed so that the straight long sections of their flow channels are alternating with each other in the plane of the radiator. The inlet collectors in both heat exchangers are located above the outlet collectors. The tubular nozzle distributor, having many nozzle orifices on the side, directed coaxially to the flow channels, and whose diameters increase successively from the end of the thermodynamic medium supply is inserted longitudinally to the inside of each inlet collectors
It is preferred when each heat exchange unit has an inter-collector insulating strip inserted between the vertically adjacent inlet collector and the outlet collector in both exchangers and above that when the surface between the outlet collectors in both heat exchangers is covered from the bottom by a counter-plate made of waterproof material with a low thermal conductivity coefficient. The counter-plate adheres to the entire surface of the flow channels and the radiator plate.
It is also expedient to realize a device in which—in both exchangers of each heat exchange unit—areas of vertically adjacent inlet collector and outlet collector pairs are covered by longitudinally waterproof, edge thermal insulation.
In the device according to the invention, each of the inner chambers is separated by horizontally arranged heat exchange units with a structure ensuring a homogeneous temperature distribution over the entire heat exchange surface. The preferred temperature effect results from the superimposition of two same tubular heat exchangers with a harp system, with opposite directed flows of the medium in alternately adjacent flow channels of both heat exchangers connected in parallel with the heat pump's thermodynamic medium circuit and which in one plane are connected by the common plate of the radiator covered with a thermal insulation counter-plate from the bottom. Local compensation of the amount of heat transmitted unidirectionally to the upper surface of the radiator by adjacent, counter-current, quantitatively equal streams of the media—being in the phases of physical transition with a constant parameter difference—is essential for the production efficiency of flat ice plates and storage capacity. De-icing phase as a result of unidirectional heat directed upwards is shortened only until the thin ice sheet is melted, which then flows upward under the insulated counter-plate of the heat exchange unit of the upper inner chamber. One can also point out to the oil drip effect preferred for the operation of the device through the final sections of the flow channels bent towards the outlet collectors, oil introduced by the compressor to the thermodynamic medium. This arrangement of the heat exchange units results in the homogeneous arrangement of the detached ice plates in the spaces between the units which, after floating up, do not freeze to the heat exchange unit located above. Counter-current system of the exchangers in the units causes that the ice plates have an even thickness over the entire surface, which facilitates their regular flow and laying in the spaces between the heat exchange units. The design of the heat exchange unit with a surface radiator and pipes arranged in one-sided radiator extrusions causes the ice plate to have a one-sidedly wavy shape, which substantially increases the efficiency of discharging the chiller because it allows free flow of water between the ice plates.
The solution of the device according to the invention is approximated by a description of an exemplary embodiment shown in the drawing, the individual figures of which show:
The device for manufacturing and storing ice according to the invention, for example, can be used as a source of chilled water at a temperature of approximately 6° C., safe for the environment in the event of a leak. Ice made from water at night at the cost of cheaper electricity is stored in the device and then the cooling energy contained therein used during operating hours of the air conditioning installation. The device is embedded in the thermodynamic medium circuit of the heat pump composed of interconnected compressor “S”, the heat exchanger “Wc”, the expansion valve “Zr” and the device according to the invention. Depending on the direction of flow of the thermodynamic medium determined by the valve unit “Z4”, the device works in the phase of ice manufacturing as an evaporator and during de-icing in the condenser function. The device comprises a closed, a heat-insulated storage tank “A” with a water reservoir “W” embedded inside having a plurality of inner chambers “K”, separated by heat exchange units 1 horizontally mounted and at intervals above each other. Each heat exchange unit 1 consists of two tubular heat exchangers: first 2 and second 3, incorporated in parallel in the thermodynamic medium circuit. The exchangers 2 and 3 have parallel inlet collectors 7.1 and 7.2 and outlet collectors 8.1 and 8.2 and are connected through the perpendicular tubular flow channels 5.1 and 5.2. The outlet collectors 8.1 and 8.2 are located below the axis level of the inlet collectors 7.1 and 7.2 by a dimension “e” greater than half the sum of the outside diameters “d1” and “d2” of the inlet 7.1, 7.2 and outlet 8.1, 8.2 collector. With such arrangement the final sections 10.1 and 10.2 of the flow channel connections 5.1 and 5.2 to the outlet collector 8.1 and 8.2 are deflected from the straight long sections of the flow channels 5.1 and 5.2 coming out from the inlet collector 7.1, 7.2. The heat exchangers 2 and 3 are superimposed so that their straight long sections of the flow channels 5.1 and 5.2 are alternating with each other in one plane 9-9 and are heat-bonded to one common plate of the radiator 4. Inlet collectors 7.1 and 7.2 in both heat exchangers 2 and 3 are arranged above the outlet collectors 8.1 and 8.2 and the inter-collector insulating strips 14, eliminating the possibility of heat exchange are introduced into the gaps in-between them. The tubular nozzle distributor 11, having many nozzle orifices 12 on the side, directed coaxially to the flow channels 5 is inserted longitudinally to the inside of the inlet collectors 7.1 and 7.2. The diameters d3 of the nozzle orifices 12 increase successively from the end of the thermodynamic medium supply. The surface between the outlet collectors 8.1 and 8.2 of both exchangers 2 and 3 is covered from the bottom by a counter-plate 6 made of waterproof material, with a low thermal conductivity coefficient. Grooves for the flow channels 5.1 and 5.2 are performed in the counter-plate 6, which allows the counter-board 6 to adhere to the entire surface of the flow channels 5.1 and 5.2 and to the plate of the radiator 4. In each heat exchange unit 1 the areas of vertically adjacent pairs of the inlet collector 7.1 and 7.2 and outlet collector 8.2 and 8.2 are longitudinally covered by the waterproof, edge thermal insulation 15.
The operation of the device depends on the flow direction of the thermodynamic medium in the heat pump circuit, the direction which determines the position of the four-way valve “Z4”. In the ice manufacturing phase, the device works as an evaporator with the flow direction of the medium indicated in the diagram of
As the ice thickness increases, the rate of ice layers build-up on the radiator 4 decreases—which is accompanied by the pressure drop in the suction line of the compressor “Sp”. The change of the operating phases of the device is made by the control system not shown in the diagram of
| Number | Date | Country | Kind |
|---|---|---|---|
| P.421393 | Apr 2017 | PL | national |
| P.425098 | Mar 2018 | PL | national |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/PL2018/000039 | Apr 2018 | US |
| Child | 16280957 | US |
