Method and apparatus for controlling ice bubble type

Abstract

The application discloses a method and device for controlling the type of bubbles in ice, and the method comprises the following steps: determining the type of bubbles in ice to be prepared; determining the required freezing rate according to the type of bubbles; starting a cold source to obtain the actual freezing rate at the freezing front; and judging whether the actual freezing rate is within the freezing rate range, and keeping the cold source parameters unchanged when the actual freezing rate is within the freezing rate range. The above control method associates the type of bubbles in ice with the freezing rate, and only needs to control the actual freezing rate at the freezing front by controlling the cold source parameters to obtain different types of bubble ice, so that the operation is convenient and simple, the cost is low, the energy consumption is low, the efficiency is high, different types of bubble ice can be prepared, and the problems that the prior art cannot prepare different types of bubble ice, consumes more energy in the ice-making process, has poor temperature control regulation accuracy, and has slow regulation freezing rate response are solved.

Description

Technical Field

[0001] This invention relates to the field of ice-making technology, and more specifically to a method and apparatus for controlling the type of air bubbles inside ice. Background Technology

[0002] Ice is a substance used in daily life and industrial production, and it is also widely found in nature. Depending on its form and internal composition, ice comes in many varieties, such as freshwater ice, brine ice, block ice, spherical ice, bubble ice, and transparent ice. Each type of ice is used in different applications due to its unique properties. The catering industry needs freshwater ice, food refrigeration needs ice rich in bubbles, ice sculpture requires ice with different bubble contents and types, and the bar and beverage industry needs block ice, spherical ice, and transparent ice. Many industries have a strong demand for ice, but each industry has different requirements for ice types. The properties and types of ice determine its applicable fields. However, traditional ice-making methods do not consider the differences in ice types, and the ice produced often cannot directly meet the personalized needs of different industries. In actual production and daily life, there is a strong practical demand for ice containing different types of bubbles.

[0003] Focus on ice often centers on the presence or absence of air bubbles, neglecting the type of bubbles. This results in ice that fails to meet individual needs. Chinese patent document CN 115164463A, "A Method for Controlling the Generation of Air Bubbles in Ice," proposes a method and apparatus for preparing transparent ice by controlling the generation of air bubbles within the ice. This method controls the presence or absence of air bubbles by controlling a low freezing rate, but it does not address the type of air bubbles. Chinese patent document CN 215983392U, "A Novel Transparent Ice Making Machine," discloses a device for producing bubble-free ice. This device works by continuously raising and lowering the liquid level in the freezing compartment, reducing the gas concentration in the water and thus suppressing the generation of air bubbles within the ice. Furthermore, another Chinese patent document, CN212778077U, "A Transparent Ice Making Device," discloses a device for producing bubble-free ice. This device uses stirring to agitate the water in the ice-making chamber, achieving the goal of freezing bubble-free ice. The above-mentioned freezing methods mainly consider the preparation of bubble ice and transparent ice without bubbles, and do not explore the preparation methods of ice containing different types of bubbles.

[0004] Existing technologies mainly focus on the presence or absence of bubbles in ice, that is, using various methods to prevent bubbles from appearing in ice, but cannot control the type of bubbles in ice. Furthermore, existing ice-making methods also have the following problems: (1) In the method of preparing transparent ice by controlling the concentration of gas molecules in front of the ice-water interface, it is impossible to accurately measure the concentration of gas molecules in practical applications, which makes it difficult to prepare transparent ice quickly; (2) In the method of preparing transparent ice by controlling the liquid level and stirring, not only is the work efficiency low and the energy consumption high, but it also generates a lot of noise.

[0005] Therefore, there is a need to develop a method and apparatus for preparing ice containing different types of bubbles. Summary of the Invention

[0006] This invention provides a method and apparatus for controlling the type of air bubbles in ice. The control method is convenient, simple, low-cost, low-energy, and highly efficient, and can prepare ice with different types of air bubbles. It solves the problems of existing technologies that cannot prepare ice with different types of air bubbles, consume a lot of energy during the ice-making process, have poor temperature control accuracy, and slow response to freezing rate adjustment.

[0007] The present invention adopts the following specific technical solution:

[0008] This invention provides a method for controlling the type of air bubbles in ice, the method comprising the following steps:

[0009] The first step is to determine the type of air bubbles in the ice to be prepared;

[0010] The second step is to determine the required freezing rate based on the type of bubble.

[0011] The third step is to turn on the cold source and obtain the actual freezing rate at the freezing front.

[0012] The fourth step is to determine whether the actual freezing rate is within the freezing rate range. If the actual freezing rate is within the freezing rate range, keep the cold source parameters unchanged.

[0013] Furthermore, in the fourth step, when the actual freezing rate is outside the freezing rate range, the cold source parameters are adjusted.

[0014] Furthermore, the cold source parameters include cooling power and cooling temperature.

[0015] Furthermore, the specific process of adjusting the cold source parameters includes:

[0016] When the actual freezing rate is lower than the freezing rate, increase the cooling power or decrease the cooling temperature until the actual freezing rate is within the freezing rate range.

[0017] When the actual freezing rate is higher than the freezing rate, reduce the cooling power or increase the cooling temperature until the actual freezing rate is within the freezing rate range.

[0018] Furthermore, the formula for calculating the actual freezing rate is:

[0019]

[0020] In the above formula, V is the actual freezing rate, k is the thermal conductivity of ice, and T is the thermal conductivity of ice. m Let ρ be the freezing phase transition temperature of water, T be the cold source temperature, ρ be the density of ice, t be the freezing time, and L be the latent heat of freezing phase transition of water.

[0021] Furthermore, the bubble types include egg-shaped bubbles and needle-shaped bubbles.

[0022] Furthermore, the freezing rate for preparing egg-shaped bubble ice is greater than or equal to 20 μm / s;

[0023] The freezing rate for preparing egg-shaped and needle-shaped bubble ice was 10 μm / s to 20 μm / s;

[0024] The freezing rate for preparing needle-like bubble ice is 3 μm / s to 10 μm / s;

[0025] The freezing rate for preparing bubble-free ice ranges from 0 μm / s to 3 μm / s.

[0026] In addition, the present invention also provides an ice control device used in the above control method, the ice control device including a heat dissipation unit, a cooling chip, a heat transfer medium, a heat insulation material, a transparent shell and a control unit;

[0027] The heat dissipation unit is attached to the hot end of the cooling chip to achieve heat dissipation of the cooling chip;

[0028] The cold end of the cooling element is in contact with the heat transfer medium;

[0029] The heat transfer medium is located at the bottom of the transparent shell and is used to conduct the cold energy generated by the cooling chip to the water inside the transparent shell, causing it to freeze into ice.

[0030] The thermal insulation material is wrapped around the outer periphery of the heat transfer medium;

[0031] The control unit is connected to the cooling chip via a signal and is used to control the cooling chip.

[0032] Furthermore, the heat dissipation unit includes a low-temperature thermostatic bath and a heat exchanger;

[0033] A refrigerant circulates between the low-temperature thermostatic bath and the heat exchanger.

[0034] Furthermore, the cooling element is an electric cooling element;

[0035] The control unit is a digital thermostat used to control the temperature of the cooling element;

[0036] The heat exchanger is a microchannel heat exchanger;

[0037] The heat transfer medium is a copper plate;

[0038] The insulation material is insulation cotton.

[0039] Beneficial effects:

[0040] This invention provides a method for controlling the type of bubbles in ice. This method correlates the type of bubbles in ice with the freezing rate. By controlling the actual freezing rate at the freezing front by controlling the cold source parameters, different types of bubble ice can be obtained. Thus, the type and presence of bubbles in ice can be changed simply by controlling the cold source parameters. The method is simple, convenient, time-saving, and energy-efficient. Therefore, this control method can not only control the presence of bubbles in ice, but also control the type of bubbles in ice, allowing egg-shaped bubbles, egg-shaped and needle-shaped bubbles, needle-shaped bubbles, and no bubbles to appear in ice. This avoids unnecessary energy consumption and noise, has high control precision, and a short preparation time. Attached Figure Description

[0041] Figure 1 This is a flowchart of the method for controlling the type of air bubbles in ice according to the present invention;

[0042] Figure 2 This is a schematic diagram of the ice control device of the present invention;

[0043] Figure 3 A schematic diagram illustrating the relationship between the type of air bubbles in ice and the freezing rate;

[0044] Figure 4 This is a schematic diagram of the experimental structure of an ice control device according to the present invention;

[0045] Figure 5 The graph shows the relationship between the cold source temperature and the freezing rate when egg-shaped and needle-shaped bubbles appear in ice.

[0046] Figure 6 The images show actual ice samples containing egg-shaped and needle-shaped bubbles.

[0047] Figure 7 The graph shows the relationship between the cold source temperature and the freezing rate when transparent ice, egg-shaped bubbles, and needle-shaped bubbles appear in ice.

[0048] Figure 8 These are photographs of ice containing transparent ice, egg-shaped bubbles, and needle-shaped bubbles.

[0049] Among them, 1-low temperature constant temperature bath, 2-water, 3-ice, 4-control unit, 5-power supply, 601-first transparent acrylic plate, 602-second transparent acrylic plate, 7-heat exchanger, 8-cooling plate, 9-copper plate, 10-insulation cotton. Detailed Implementation

[0050] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] Example 1

[0052] This embodiment provides a method for controlling the type of air bubbles inside ice, such as... Figure 1 As shown, this control method correlates the presence and type of air bubbles in ice with parameters such as freezing rate, cold source temperature, and power. It adjusts parameters such as the cold source temperature based on the relative magnitude of the actual freezing rate and the expected freezing rate, ultimately controlling the appearance of the desired air bubble type in the ice. The cold source parameters include refrigeration power and refrigeration temperature. In this embodiment, the cold source temperature is used as an example for illustration. The control method includes the following steps:

[0053] The first step is to determine the type of bubbles in the ice to be prepared; bubble types include egg-shaped bubbles and needle-shaped bubbles.

[0054] The second step is to determine the required freezing rate V based on the bubble type. i ~V i+1 ;like Figure 3 As shown, the freezing rate for preparing egg-shaped bubble ice is greater than or equal to 20 μm / s; the freezing rate for preparing egg-shaped and needle-shaped bubble ice is 10 μm / s to 20 μm / s; the freezing rate for preparing needle-shaped bubble ice is 3 μm / s to 10 μm / s; and the freezing rate for preparing bubble-free ice is 0 μm / s to 3 μm / s.

[0055] The third step is to turn on the cold source and obtain the actual freezing rate V at the freezing front; the formula for calculating the actual freezing rate V is:

[0056]

[0057] In the above formula, V is the actual freezing rate, k is the thermal conductivity of ice, and T is the thermal conductivity of ice. m Let T be the freezing phase transition temperature of water, ρ be the density of ice, t be the freezing time, and L be the latent heat of freezing phase transition of water.

[0058] The height h of the frozen front can be calculated using the following formula:

[0059]

[0060] The fourth step is to determine whether the actual freezing rate V is within the freezing rate range V. i ~V i+1 Within the freezing rate range, maintain the cold source temperature constant; when the actual freezing rate is outside the freezing rate range, adjust the cold source temperature T; the specific process of adjusting the cold source temperature includes:

[0061] When the actual freezing rate is lower than the freezing rate, the cooling temperature is reduced until the actual freezing rate is within the freezing rate range.

[0062] When the actual freezing rate is higher than the freezing rate, the cooling temperature is increased until the actual freezing rate is within the freezing rate range.

[0063] The above-described method for controlling the type of bubbles in ice correlates the type of bubbles in ice with the freezing rate. By controlling the actual freezing rate at the freezing front simply by controlling the cold source parameters, different types of bubble ice can be obtained. This allows for changing the type and presence of bubbles in ice simply by controlling the cold source parameters. The method is simple, convenient, time-saving, and energy-efficient. Therefore, this control method can not only control the presence or absence of bubbles in ice, but also control the type of bubbles in ice, allowing egg-shaped bubbles, egg-shaped and needle-shaped bubbles, needle-shaped bubbles, and no bubbles to appear in the ice. This avoids ineffective energy consumption and noise, and offers high control precision and short preparation time.

[0064] Example 2

[0065] This embodiment provides an ice control device used in the above-described method for controlling the type of air bubbles within ice, such as... Figure 2 and Figure 4As shown, the ice control device includes a heat dissipation unit, a cooling chip 8, a heat transfer medium, insulation material, a transparent shell, and a control unit 4. The heat dissipation unit is attached to the hot end of the cooling chip 8 to dissipate heat and ensure the cooling chip 8 can work normally. The heat dissipation unit includes a low-temperature constant temperature bath 1 and a heat exchanger 7. A refrigerant circulates between the low-temperature constant temperature bath 1 and the heat exchanger 7. The heat exchanger 7 is a microchannel heat exchanger with dimensions of 40mm × 40mm × 20mm. The cold end of the cooling chip 8 is attached to the heat transfer medium. The cooling chip 8 is an electric cooling chip and is connected to a power supply 5. The structure of the cooling chip 8 can be a rectangular parallelepiped with dimensions of 40mm × 40mm × 10mm. The heat transfer medium is located in the transparent shell. At the bottom, the cooling energy generated by the cooling element 8 is conducted to the water 2 inside the transparent shell, causing it to freeze into ice 3. The heat transfer medium can be a copper plate 9 with dimensions of 40mm × 50mm × 0.5mm. The transparent shell can be composed of a first transparent acrylic plate 601 and a second transparent acrylic plate 602 with a thickness of 5mm, forming a cavity with a 0.5mm gap between the first transparent acrylic plate 601 and the second transparent acrylic plate 602. The water 2 is placed inside the transparent shell and gradually freezes into ice 3 at the low temperature of the heat transfer medium. The freezing phase change temperature of the water 2 is 0℃, and the latent heat of freezing phase change is 334kJ / kg. The thermal conductivity of the ice 3 is 2.2W / (m·K), and the density is 917kg / m³. 3 The insulation material, specifically insulation cotton 10, is wrapped around the outer periphery of the heat transfer medium to minimize the loss of cold energy from the heat transfer medium. The control unit 4 is connected to the cooling element 8 via a signal connection and is used to control the cooling element 8. The control unit 4 can be a digital thermostat used to control the cooling temperature of the cooling element 8. The control unit 4 is connected to the power supply 5 via a wire. The power supply 5 uses AC power to supply power to the control unit 4.

[0066] use Figure 4 The ice control device shown in the study revealed that egg-shaped bubbles appear in the ice when the freezing rate is greater than 10 μm / s; needle-shaped bubbles appear when the freezing rate is less than 20 μm / s; and no bubbles appear when the freezing rate is less than 3 μm / s. Therefore, based on the freezing rate thresholds for these two types of bubbles, adjusting the freezing rate value is sufficient to induce the appearance of specific bubble types in the ice. When egg-shaped bubbles are desired, the freezing rate cannot be less than 20 μm / s; when both egg-shaped and needle-shaped bubbles appear, the freezing rate is between 10 μm / s and 20 μm / s; when needle-shaped bubbles appear, the freezing rate is between 3 μm / s and 10 μm / s; and when bubbles are not desired, the freezing rate is less than 3 μm / s. Figure 5 and Figure 6 The temperature control curves and freezing rate curves, as well as the morphology of bubbles in ice 3, are shown when egg-shaped and needle-shaped bubbles appear in the ice, respectively, to control the cold source temperature and maintain the freezing rate between 10 μm / s and 20 μm / s.

[0067] When the temperature of the cold source is changed, the freezing rate also changes accordingly, and the type of air bubbles in the ice also changes. Therefore, by changing the temperature of the cold source to keep the freezing rate below 3 μm / s and between 10 μm / s and 20 μm / s, respectively, a structure of alternating transparent ice and air bubbles can be formed in the ice. Figure 7 and Figure 8 The corresponding temperature control curve, freezing rate change curve, and bubbles appearing in the ice are shown respectively.

[0068] Obviously, those skilled in the art can make various modifications and variations to the embodiments of the present invention without departing from the spirit and scope of the invention. Therefore, if these modifications and variations fall within the scope of the claims of the present invention and their equivalents, the present invention also intends to include these modifications and variations.

Claims

1. A method for controlling the type of air bubbles in ice, characterized in that, Includes the following steps: The first step is to determine the type of bubbles in the ice to be prepared; the bubble type includes egg-shaped bubbles and needle-shaped bubbles; the freezing rate for preparing egg-shaped bubble ice is greater than or equal to 20 μm / s; the freezing rate for preparing egg-shaped and needle-shaped bubble ice is 10 μm / s ~ 20 μm / s; the freezing rate for preparing needle-shaped bubble ice is 3 μm / s ~ 10 μm / s; and the freezing rate for preparing bubble-free ice is 0 μm / s ~ 3 μm / s. The second step is to determine the required freezing rate based on the type of bubble. The third step is to turn on the cold source and obtain the actual freezing rate at the freezing front. The fourth step is to determine whether the actual freezing rate is within the freezing rate range. If the actual freezing rate is within the freezing rate range, keep the cold source parameters unchanged; if the actual freezing rate is outside the freezing rate range, adjust the cold source parameters.

2. The method as described in claim 1, characterized in that, The parameters of the cold source include cooling power and cooling temperature.

3. The method as described in claim 2, characterized in that, The specific process of adjusting the cold source parameters includes: When the actual freezing rate is lower than the freezing rate, increase the cooling power or decrease the cooling temperature until the actual freezing rate is within the freezing rate range. When the actual freezing rate is higher than the freezing rate, reduce the cooling power or increase the cooling temperature until the actual freezing rate is within the freezing rate range.

4. The method according to any one of claims 1-3, characterized in that, The formula for calculating the actual freezing rate is: ； In the above formula, V This represents the actual freezing rate. k Let be the thermal conductivity of ice. T m The freezing phase transition temperature of water. T The temperature of the cold source. ρ The density of ice, t For the freeze time, L It is the latent heat of the solidification phase transition of water.

5. An ice-controlling device used in the control method according to any one of claims 1-4, characterized in that, It includes a heat dissipation unit, a cooling chip, a heat transfer medium, insulation material, a transparent housing, and a control unit; The heat dissipation unit is attached to the hot end of the cooling chip to achieve heat dissipation of the cooling chip; The cold end of the cooling element is in contact with the heat transfer medium; The heat transfer medium is located at the bottom of the transparent shell and is used to conduct the cold energy generated by the cooling chip to the water inside the transparent shell, causing it to freeze into ice. The thermal insulation material is wrapped around the outer periphery of the heat transfer medium; The control unit is connected to the cooling chip via a signal and is used to control the cooling chip.

6. The ice control device as described in claim 5, characterized in that, The heat dissipation unit includes a low-temperature thermostatic bath and a heat exchanger; A refrigerant circulates between the low-temperature thermostatic bath and the heat exchanger.

7. The ice control device as described in claim 5, characterized in that, The cooling element is an electro-cooling element; The control unit is a digital thermostat used to control the temperature of the cooling element; The heat exchanger is a microchannel heat exchanger; The heat transfer medium is a copper plate; The insulation material is insulation cotton.

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