A control method and device of a vehicle-mounted refrigerator and the vehicle-mounted refrigerator

Abstract

This invention discloses a control method, device, and vehicle-mounted refrigerator for a vehicle-mounted refrigerator, relating to the field of refrigeration equipment technology. The method includes: controlling the refrigerator door to open for heat exchange based on the initial internal temperature difference between the refrigerator and the ambient temperature being greater than a preset temperature difference threshold; determining the real-time heat exchange capacity of the refrigerator based on the real-time internal temperature and the ambient temperature; and controlling the door to close based on the real-time heat exchange capacity being less than a preset heat exchange threshold. Controlling the refrigerator door to open for heat exchange based on the initial internal temperature difference between the refrigerator and the ambient temperature being greater than the preset temperature difference threshold improves the efficiency of opening the door for heat exchange, reduces time consumption, and lowers the energy consumption required for heat exchange. Controlling the door to close based on the real-time heat exchange capacity being less than the preset heat exchange threshold avoids reduced heat exchange efficiency due to low real-time heat exchange capacity and also reduces time consumption.

Description

Technical Field

[0001] This invention relates to the field of refrigeration equipment, and more specifically to a control method, device, and vehicle-mounted refrigerator for a vehicle-mounted refrigerator. Background Technology

[0002] Existing car refrigerators have heating and cooling modes. Typically, heating wires are wrapped around the inner liner to generate heat, achieving the heating mode. The target temperature in heating mode is usually between 25 and 50°C. Using heating wires to raise the internal temperature from a low temperature to the target high temperature is time-consuming and energy-intensive. For cooling mode, the target temperature is usually between 0 and 12°C or lower. In cooling mode, lowering the internal temperature from a high temperature to the target low temperature is also time-consuming and energy-intensive. Summary of the Invention

[0003] This invention provides a control method, device, and vehicle-mounted refrigerator. By controlling the refrigerator door to open for heat exchange when the initial internal temperature difference between the internal temperature and the ambient temperature exceeds a preset temperature difference threshold, heat exchange is performed, thereby reducing time and energy consumption. When the real-time heat exchange is less than or equal to the preset heat exchange threshold, the door is closed to prevent reduced heat exchange efficiency due to low real-time heat exchange, further reducing time consumption.

[0004] To achieve the above objectives, the embodiments of this application provide the following technical solutions:

[0005] According to a first aspect of the embodiments of this application, a control method for a vehicle-mounted refrigerator is provided, the method comprising:

[0006] If the temperature difference between the initial internal temperature of the refrigerator and the ambient temperature is greater than a preset temperature difference threshold, the refrigerator door is controlled to open for heat exchange.

[0007] The real-time heat exchange of the refrigerator is determined based on the real-time internal temperature of the refrigerator and the ambient temperature.

[0008] The door is controlled to close when the real-time heat exchange is less than a preset heat exchange threshold.

[0009] Optionally, controlling the refrigerator door to open for heat exchange based on the initial internal temperature difference between the refrigerator and the ambient temperature being greater than a preset temperature difference threshold includes:

[0010] Based on the fact that the ambient temperature is between the initial internal temperature and the target temperature, and the temperature difference between the initial internal temperature and the ambient temperature is greater than a preset temperature difference threshold, the refrigerator door is controlled to open for heat exchange.

[0011] Optionally, determining the real-time heat exchange capacity of the refrigerator based on its real-time internal temperature and the ambient temperature includes:

[0012] The Prandtl number and Grashof number are determined based on the real-time internal temperature, the ambient temperature, and the air properties.

[0013] The real-time heat exchange is determined based on the Prandtl number, the Grashof number, and the surface area of ​​the refrigerator liner.

[0014] Optionally, determining the Prandtl number and Grashof number based on the real-time internal temperature, the ambient temperature, and air properties includes:

[0015] The Prandtl number is determined based on the dynamic viscosity coefficient, thermal conductivity coefficient, and specific heat capacity at constant pressure among the air physical properties.

[0016] The Grashof number is determined based on the real-time internal temperature, the ambient temperature, gravitational acceleration, and the coefficient of thermal expansion, heat transfer length, and kinematic viscosity of the air physical properties.

[0017] Optionally, determining the real-time heat exchange based on the Prandtl number, the Grashof number, and the surface area of ​​the refrigerator liner includes:

[0018] The real-time heat exchange is determined based on the Prandtl number, the Grashof number, the thermal conductivity, the real-time internal temperature, the ambient temperature, and the surface area of ​​the refrigerator liner.

[0019] Optionally, it also includes:

[0020] While controlling the door to open, the fan inside the refrigerator is also turned on for heat exchange.

[0021] Optionally, determining the real-time heat exchange capacity of the refrigerator based on its real-time internal temperature and the ambient temperature includes:

[0022] The Prandtl number and Reynolds number are determined based on the real-time internal temperature, the ambient temperature, and the air physical properties.

[0023] The real-time heat exchange is determined based on the Prandtl number, the Reynolds number, and the surface area of ​​the refrigerator liner.

[0024] Optionally, determining the Prandtl number and Reynolds number based on the real-time internal temperature, the ambient temperature, and air physical properties includes:

[0025] The Prandtl number is determined based on the dynamic viscosity coefficient, thermal conductivity coefficient, and specific heat capacity at constant pressure among the air physical properties.

[0026] The Reynolds number is determined based on the fluid density, fluid velocity, heat transfer length, and dynamic viscosity coefficient in the air physical properties.

[0027] Optionally, determining the real-time heat exchange based on the Prandtl number, the Reynolds number, and the surface area of ​​the refrigerator liner includes:

[0028] The current heat exchange is determined based on the Prandtl number, the Reynolds number, the thermal conductivity, the real-time internal temperature, the ambient temperature, and the surface area of ​​the refrigerator liner.

[0029] Optionally, before controlling the refrigerator door to open for heat exchange based on the initial internal temperature difference between the refrigerator and the ambient temperature being greater than a preset temperature difference threshold, the method further includes:

[0030] Confirm that the refrigerator's operating mode has switched from a first mode to a second mode; wherein the first mode includes one of a cooling mode and a heating mode, and the second mode includes the other.

[0031] According to a second aspect of the embodiments of this application, a control device for a vehicle-mounted refrigerator is provided, the device comprising:

[0032] The first control module is used to control the refrigerator door to open for heat exchange when the temperature difference between the initial internal temperature of the refrigerator and the ambient temperature is greater than a preset temperature difference threshold.

[0033] The heat exchange determination module is used to determine the real-time heat exchange of the refrigerator based on the real-time internal temperature of the refrigerator and the ambient temperature.

[0034] The second control module is used to control the door to close when the real-time heat exchange is less than a preset heat exchange threshold.

[0035] According to a third aspect of the embodiments of this application, a vehicle refrigerator is provided, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the control method described in the first aspect above.

[0036] In summary, this application provides a control method, device, and vehicle-mounted refrigerator for a vehicle-mounted refrigerator. By controlling the refrigerator door to open for heat exchange based on the initial internal temperature difference between the refrigerator and the ambient temperature being greater than a preset temperature difference threshold, the efficiency of opening the door for heat exchange is improved, reducing time consumption and energy consumption required for heat exchange is reduced. The real-time heat exchange capacity of the refrigerator is determined based on the real-time internal temperature and the ambient temperature. If the real-time heat exchange capacity is less than a preset heat exchange capacity threshold, the door is controlled to close. This avoids reduced heat exchange efficiency due to low real-time heat exchange capacity and reduces time consumption. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0038] The structures, proportions, sizes, etc. illustrated in this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0039] Figure 1 This application provides a schematic diagram of the flow of a control method for a vehicle-mounted refrigerator;

[0040] Figure 2 A schematic diagram of the structure of a vehicle-mounted refrigerator provided in an embodiment of this application for controlling a vehicle-mounted refrigerator;

[0041] Figure 3 A schematic diagram of a control device for a vehicle-mounted refrigerator provided in an embodiment of this application;

[0042] Figure 4 A schematic diagram of the structure of a vehicle-mounted refrigerator provided in an embodiment of this application is shown.

[0043] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0044] 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 a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0045] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0046] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0047] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0048] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0049] Figure 1 This application illustrates a control method for a vehicle-mounted refrigerator, which includes steps S101 to S103.

[0050] In step S101: If the temperature difference between the initial internal temperature of the refrigerator and the ambient temperature is greater than a preset temperature difference threshold, the refrigerator door is opened for heat exchange.

[0051] The initial internal temperature can be the temperature inside the refrigerator when this control method is enabled. The ambient temperature can be the temperature of the environment outside the refrigerator. The temperature difference between the initial internal temperature and the ambient temperature can be understood as the difference between the initial internal temperature and the ambient temperature. The preset temperature difference threshold can be set as needed.

[0052] Whether in cooling or heating mode, a refrigerator needs to reach the target temperature. When the initial internal temperature difference between the refrigerator and the ambient temperature is greater than the preset temperature difference threshold, it indicates that the initial internal temperature difference between the two is relatively large. In this case, the refrigerator door can be opened to allow natural convection heat exchange between the refrigerator interior and the environment, thereby reducing the temperature difference between the refrigerator interior and the target temperature.

[0053] In step S102: Determine the real-time heat exchange of the refrigerator based on the real-time internal temperature of the refrigerator and the ambient temperature.

[0054] Real-time internal temperature can be understood as the temperature inside the refrigerator obtained through real-time monitoring. When the refrigerator door is opened, heat exchange occurs between the refrigerator and the environment, causing the internal temperature to change in real time. Therefore, the real-time internal temperature of the refrigerator is variable. Based on the real-time internal temperature and the ambient temperature, the real-time heat exchange between the refrigerator and the environment can be obtained.

[0055] In step S103: If the real-time heat exchange is less than the preset heat exchange threshold, control the door to close.

[0056] The preset heat exchange threshold can be set as needed. When the real-time heat exchange is less than the preset heat exchange threshold, it indicates that the refrigerator can no longer obtain enough energy from the external environment. At this time, the door needs to be closed, and the refrigerator's heating or cooling mode should be used to reach the target temperature.

[0057] The technical solution of this disclosure embodiment involves opening the refrigerator door when the initial internal temperature difference between the refrigerator and the ambient temperature exceeds a preset temperature difference threshold. This allows energy exchange between the refrigerator's interior and the external environment, reducing the difference between the initial internal temperature and the target temperature. During this heat exchange process, the real-time heat exchange is determined based on the refrigerator's real-time internal temperature and the ambient temperature. When the real-time heat exchange is less than the preset heat exchange threshold, the door is closed. This process first uses heat exchange between the external environment and the refrigerator's interior to reduce the temperature difference between the refrigerator's interior and the target temperature. Then, a heating or cooling mode is used to bring the refrigerator's interior temperature to the target temperature. This reduces the energy consumption of the heating or cooling mode and shortens the time it takes for the refrigerator to reach the target temperature from the initial internal temperature.

[0058] In one possible implementation, before step S101, before controlling the refrigerator door to open for heat exchange based on the temperature difference between the initial internal temperature of the refrigerator and the ambient temperature being greater than a preset temperature difference threshold, the method further includes: confirming that the refrigerator's operating mode has switched from a first mode to a second mode; wherein the first mode includes one of a cooling mode and a heating mode, and the second mode includes the other.

[0059] Because the target temperatures in a refrigerator's cooling and heating modes differ significantly, when switching from cooling to heating mode, or vice versa, opening the refrigerator door allows energy exchange between the interior and the external environment. This quickly brings the initial internal temperature closer to ambient temperature, reducing the difference between the initial and target temperatures. Then, switching to heating or cooling mode allows the refrigerator to reach the target temperature, thus reducing energy consumption and shortening the time required for the temperature to rise from the initial internal temperature to the target temperature.

[0060] In one possible implementation, in step S101, controlling the refrigerator door to open for heat exchange based on the temperature difference between the initial internal temperature and the ambient temperature being greater than a preset temperature difference threshold includes: controlling the refrigerator door to open for heat exchange based on the ambient temperature being between the initial internal temperature and the target temperature, and the temperature difference between the initial internal temperature and the ambient temperature being greater than a preset temperature difference threshold.

[0061] The preset temperature difference threshold includes 20 degrees Celsius. The initial internal temperature can be the internal temperature of the refrigerator before it starts heating or cooling.

[0062] Taking a refrigerator with an initial internal temperature of high and a target temperature of low as an example, let's consider the process of reducing the refrigerator's internal temperature t1 to the target temperature t2. First, the temperature difference |t1-t| is determined based on the initial internal temperature and the ambient temperature t. If the temperature difference |t1-t| is greater than a preset temperature difference threshold, the natural convection temperature difference is considered sufficient, and the refrigerator door is automatically opened for heat exchange. If the vehicle's air conditioning is on when the temperature difference is greater than the preset threshold, the natural convection temperature difference will be even better.

[0063] By setting a preset temperature difference threshold, the refrigerator door will only be opened for heat exchange when the temperature difference between the initial internal temperature and the ambient temperature is greater than the preset temperature difference threshold and the ambient temperature is between the initial internal temperature and the target temperature. This can improve the efficiency of heat exchange by opening the door, reduce heat exchange time, and also reduce heat exchange energy consumption.

[0064] In one possible implementation, in step S102, the real-time heat exchange of the refrigerator is determined based on the real-time internal temperature and ambient temperature, including: determining the Prandtl number (Pr) and Grashof number (Gr) based on the real-time internal temperature, ambient temperature and air physical properties; and determining the real-time heat exchange based on the Prandtl number, Grashof number and the surface area of ​​the refrigerator liner.

[0065] like Figure 2 As shown, 1 is the fan inside the car refrigerator, and 2 is the refrigerator liner. Because the car refrigerator door is on its top (… Figure 2 The refrigerator door is not shown in the image (it is located at the top of the inner liner 2). Therefore, when the door is open and heat is exchanged through self-heating convection, there are very few external forces affecting natural convection. The real-time heat exchange can be determined based on the Grashof number, which reflects the ratio of buoyancy to viscous force under natural convection conditions, the Prandtl number, which describes the relative rate of momentum transfer to heat transfer in a fluid, and the surface area of ​​the inner liner of the refrigerator.

[0066] In one possible implementation, the Prandtl number and Grashof number are determined based on real-time internal temperature, ambient temperature, and air properties, including: determining the Prandtl number based on the dynamic viscosity coefficient, thermal conductivity coefficient, and isobaric specific heat capacity among the air properties; and determining the Grashof number based on real-time internal temperature, ambient temperature, gravitational acceleration, and the thermal expansion coefficient, heat transfer length, and kinematic viscosity among the air properties.

[0067] Taking the real-time internal temperature detected from inside the refrigerator, such as the refrigerator liner, as ti, and the ambient temperature as te, as an example, the determination of Prandtl number and Grashof number will be further explained.

[0068] First, it's necessary to determine whether the current airflow is laminar or turbulent. Since heat exchange is only controlled by opening the refrigerator door, the influence of external forces during the entire heat exchange process is relatively small. Therefore, it is usually laminar flow, meaning the fluid flows along parallel planes with small velocity differences, relatively ordered relative motion between fluid particles, and the velocity and direction of the flow remain almost constant at all locations. The flow is uniform, streamlines are parallel, and there is no significant mixing or exchange between fluid particles. Therefore, the Nusselt number can be determined based on the Prandtl number and the Grashof number.

[0069] Secondly, the Prandtl number Pr is determined as follows:

[0070]

[0071] Where Pr represents the Prandtl number, c p This represents the specific heat capacity at constant pressure, which in this formula is the specific heat capacity of air, obtained through... The unit is joules per kilogram per degree Celsius (J / (kg*K)); μ represents the dynamic viscosity coefficient, which is in Newtons per second (Pa*s); λ represents the thermal conductivity coefficient, which is the thermal conductivity coefficient of air used in this formula, and its unit is watts per meter per Kelvin (W / (m*K)).

[0072] Finally, the Grashof number Gr is determined as follows:

[0073]

[0074] Where Gr represents the Grashof number, which characterizes the buoyancy and viscous forces in natural fluid convective heat transfer; g represents gravitational acceleration; α represents the thermal expansion coefficient; Δt represents the temperature difference; l represents the characteristic length, also known as the heat transfer length; and v represents the kinematic viscosity coefficient, with units of square meters per second (m²). 2 / s). The temperature difference Δt is determined based on the real-time internal temperature ti and the ambient temperature te, and the temperature difference Δt = ti - te. When the refrigerator door is open for heat exchange, according to natural convection heat exchange through the walls, the average temperature tm = (te + ti) / 2. The kinematic viscosity coefficient v is determined based on its ratio to the fluid density ρ, i.e., kinematic viscosity coefficient v = μ / ρ. The fluid density ρ is the air density, and its unit is kilograms per cubic meter (kg / m³). 3 ).

[0075] In one possible implementation, determining the real-time heat exchange based on Prandtl number, Grashof number, and the surface area of ​​the refrigerator liner includes: determining the real-time heat exchange based on Prandtl number, Grashof number, thermal conductivity, real-time internal temperature, ambient temperature, and the surface area of ​​the refrigerator liner.

[0076] First, in the case of laminar flow, the Nusselt number Nu is determined as follows:

[0077]

[0078] Secondly, the convective heat transfer coefficient h is determined based on the Nusselt number Nu, the thermal conductivity λ, and the characteristic length l; this is the convective heat transfer coefficient with air. The convective heat transfer coefficient h is determined as follows:

[0079]

[0080] Finally, the real-time heat exchange rate φ is determined based on the refrigerator's inner liner surface area S, the heat transfer coefficient h, and the temperature difference Δt. The real-time heat exchange rate φ is determined as follows:

[0081] Φ=S*h*(ti-te)=S*h*Δt

[0082] The surface area S of the refrigerator's inner liner can be approximated as a cuboid. The calculated real-time heat exchange rate φ is compared with a preset heat exchange rate threshold. If the real-time heat exchange rate φ is greater than or equal to the preset threshold, the real-time internal temperature is continuously acquired, and the real-time heat exchange rate φ is determined based on the real-time internal temperature. If the real-time heat exchange rate φ is less than the preset threshold, heat exchange is considered slow, and the refrigerator door is closed, and the refrigerator's compressor is used for cooling, or heating wires are used for heating.

[0083] In one possible implementation, the control method further includes: controlling the fan inside the refrigerator to turn on for heat exchange while controlling the door to open.

[0084] By controlling the refrigerator door to open and simultaneously turning on the internal fan for heat exchange, the natural convection between the refrigerator's interior and the external environment can be accelerated. This reduces power consumption while speeding up the refrigerator's cooling or heating process, thereby improving the heat exchange efficiency between the refrigerator's interior and the external environment.

[0085] In one possible implementation, in step S102, the real-time heat exchange of the refrigerator is determined based on the real-time internal temperature and ambient temperature, including: determining the Prandtl number and Reynolds number (Re) based on the real-time internal temperature, ambient temperature and air physical properties; and determining the real-time heat exchange based on the Prandtl number, Reynolds number and the surface area of ​​the refrigerator liner.

[0086] In one possible implementation, the Prandtl number and Reynolds number are determined based on real-time internal temperature, ambient temperature, and air physical properties, including: determining the Prandtl number based on the dynamic viscosity coefficient, thermal conductivity coefficient, and specific heat capacity at constant pressure in the air physical properties; and determining the Reynolds number based on the fluid density, fluid velocity, heat transfer length, and dynamic viscosity coefficient in the air physical properties.

[0087] Taking the forced convection of heat exchange by controlling the fan inside the refrigerator to turn on, with the initial internal temperature of the refrigerator as high and the target temperature as low, and the refrigerator dropping from the initial internal temperature t1 to the target temperature t2 as an example, the method of obtaining the Reynolds number is further explained.

[0088] The temperature difference is determined as |t1-t| based on the initial internal temperature and ambient temperature t. If the temperature difference |t1-t| is greater than the preset temperature difference threshold, the natural convection temperature difference is considered sufficient. The refrigerator door is then automatically opened, and the internal fan is activated to blow air for heat exchange. If the vehicle's air conditioning is on when the temperature difference exceeds the preset threshold, the natural convection temperature difference will be even better.

[0089] First, it's necessary to determine whether the current airflow is laminar or turbulent. Since the refrigerator's fan turns on for heat exchange simultaneously with the door opening, the current airflow is turbulent heat transfer. Therefore, the Nusselt number can be determined using the Prandtl number and the Reynolds number. The Reynolds number Re is determined as follows:

[0090] Re=ρvL / μ

[0091] Where Re represents the Reynolds number, μ represents the dynamic viscosity coefficient, with units of Newton-seconds (Pa·s), and v represents the kinematic viscosity coefficient, with units of square meters per second (m²). 2 / s); l represents the characteristic length; ρ represents the fluid density, usually air density, with units of kilograms per cubic meter (kg / m³). 3 The method for determining the Prandtl number based on the dynamic viscosity coefficient, thermal conductivity coefficient, and specific heat capacity at constant pressure in air physical properties is the same and will not be repeated here.

[0092] When controlling the refrigerator door to open for heat exchange, calculating the Reynolds number used to determine the real-time heat exchange can make the subsequent real-time heat exchange more accurate.

[0093] In one possible implementation, the real-time heat exchange is determined based on Prandtl number, Reynolds number, and the surface area of ​​the refrigerator liner, including: determining the current heat exchange based on Prandtl number, Reynolds number, thermal conductivity, real-time internal temperature, ambient temperature, and the surface area of ​​the refrigerator liner.

[0094] Among these, the Nusselt number is determined under turbulent conditions. The Dietus-Belt formula can be used to determine the Nusselt number (Nu) in cases of turbulent flow generated during heat exchange in a fan. f Nusselt f Determined according to the following method

[0095]

[0096] Among them, Re f Represents the Reynolds number Re under heat exchange conditions in a fan; Pr f This represents the Prandtl number Pr under fan heat exchange conditions. 0.8 is the exponent of the Reynolds number Ref under fan heat exchange conditions, and n is the Prandtl number Pr under fan heat exchange conditions. f The index. When the fan inside the refrigerator is turned on for heat exchange, causing the refrigerator to heat up, n = 0.4; when the fan inside the refrigerator is turned on for heat exchange, causing the refrigerator to cool down, n = 0.3.

[0097] Then, the convective heat transfer coefficient h is determined based on the Nusselt number Nu, the thermal conductivity λ, and the characteristic length l, and the Nusselt number Nu under the fan heat transfer condition is then calculated. f The Nusselt number is represented by Nu. Finally, the real-time heat transfer rate φ is determined based on the refrigerator's inner liner surface area S, the convective heat transfer coefficient h, and the temperature difference Δt. The determination methods for the convective heat transfer coefficient h and the real-time heat transfer rate φ are the same and will not be repeated here.

[0098] When controlling the refrigerator door to open for heat exchange, determining the real-time heat exchange using the Dittus-Belt formula can make the obtained real-time heat exchange more accurate.

[0099] By comparing the calculated real-time heat exchange φ with the preset heat exchange threshold, if the real-time heat exchange φ is greater than or equal to the preset heat exchange threshold, the real-time internal temperature is continuously acquired, and the real-time heat exchange φ is determined based on the real-time internal temperature; if the real-time heat exchange φ is less than the preset heat exchange threshold, it is considered that the heat exchange is slow, and at this time the door is controlled to close, and the compressor inside the refrigerator is used for cooling, or the heating wire is used for heating.

[0100] When controlling the refrigerator's internal fan for heat exchange, the fan rotates in different directions depending on whether the refrigerator needs to heat up or cool down. If the refrigerator needs to cool down due to high internal temperature, the fan rotates forward to dissipate heat; conversely, if the refrigerator needs to heat up due to low internal temperature, the fan rotates in reverse to absorb heat.

[0101] In summary, this application provides a control method for an in-vehicle refrigerator. By controlling the refrigerator door to open for heat exchange when the temperature difference is greater than a preset temperature difference threshold, the efficiency of heat exchange through door opening can be improved, reducing time consumption and energy consumption required for heat exchange. Real-time calculation of the refrigerator's heat exchange capacity, and controlling the door to close when the real-time heat exchange capacity is less than a preset heat exchange capacity threshold, avoids reduced heat exchange efficiency due to low real-time heat exchange capacity and reduces time consumption. By controlling the refrigerator's internal fan to start simultaneously with door opening for heat exchange, the cooling or heating rate of the refrigerator can be accelerated while reducing power consumption, thereby improving the refrigerator's heat exchange efficiency. When controlling the refrigerator door to open for heat exchange, calculating the Reynolds number used to determine the real-time heat exchange capacity and determining the real-time heat exchange capacity using the Dittus-Belt formula makes the obtained real-time heat exchange capacity more accurate. In the implementation of this application, if the initial internal temperature and ambient temperature difference is large during heating, exceeding a preset temperature difference threshold (e.g., from a high temperature of 50°C to a low temperature of -12°C, the temperature difference is greater than 30°C), and the ambient temperature is detected to be relatively low (e.g., more than 20°C below the initial internal temperature), and in the cooling mode, if the temperature needs to be raised from the lowest temperature of -12°C to the highest temperature of 50°C, and the ambient temperature is detected to be relatively high (e.g., more than 20°C above the initial internal temperature), the refrigerator door is opened for heat exchange, allowing the internal temperature to rise or fall rapidly. Then, if the real-time heat exchange is less than a preset heat exchange threshold, the door is closed, and the refrigerator's heating element is used for heating or its compressor for cooling, thereby achieving rapid temperature balance and saving power.

[0102] Based on the same technical concept, embodiments of this application also provide a control device for a vehicle-mounted refrigerator, such as... Figure 3 As shown, the device includes:

[0103] The first control module 101 is used to control the refrigerator door to open for heat exchange when the temperature difference between the initial internal temperature of the refrigerator and the ambient temperature is greater than a preset temperature difference threshold.

[0104] The heat exchange determination module 102 is used to determine the real-time heat exchange of the refrigerator based on the real-time internal temperature and ambient temperature of the refrigerator.

[0105] The second control module 103 is used to control the door to close when the real-time heat exchange is less than the preset heat exchange threshold.

[0106] This application also provides a vehicle-mounted refrigerator corresponding to the method provided in the foregoing embodiments. Please refer to... Figure 4 The diagram illustrates a vehicle refrigerator according to some embodiments of this application. The vehicle refrigerator 20 may include: a processor 200, a memory 201, a bus 202, and a communication interface 203. The processor 200, communication interface 203, and memory 201 are connected via the bus 202. The memory 201 stores a computer program that can run on the processor 200. When the processor 200 runs the computer program, it executes the control method provided in any of the foregoing embodiments of this application.

[0107] The memory 201 may include high-speed random access memory (RAM) or non-volatile memory, such as at least one disk storage device. Communication between this system network element and at least one other network element is achieved through at least one physical port (which can be wired or wireless), such as the Internet, wide area network, local area network, or metropolitan area network.

[0108] Bus 202 can be an ISA bus, PCI bus, or EISA bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. The memory 201 is used to store programs. After receiving an execution instruction, the processor 200 executes the program. The method disclosed in any of the foregoing embodiments of this application can be applied to the processor 200, or implemented by the processor 200.

[0109] The processor 200 may be an integrated circuit chip with signal processing capabilities. In implementation, each step of the above method can be completed by the integrated logic circuitry in the hardware of the processor 200 or by instructions in software form. The processor 200 may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), an off-the-shelf programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this application can be directly embodied in the execution of a hardware decoding processor, or executed by a combination of hardware and software modules in the decoding processor. The software modules may reside in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. The storage medium is located in memory 201. The processor 200 reads the information in memory 201 and, in conjunction with its hardware, completes the steps of the above method.

[0110] The vehicle refrigerator provided in this application embodiment and the method provided in this application embodiment are based on the same inventive concept and have the same beneficial effects as the methods used, operated or implemented.

[0111] It should be noted that the above embodiments are illustrative of this application and not restrictive, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. This application can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

[0112] The above description is merely a preferred embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0113] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made under the concept of the present invention using the contents of the present invention specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A control method for a vehicle-mounted refrigerator, characterized in that, The method includes: If the temperature difference between the initial internal temperature of the refrigerator and the ambient temperature is greater than a preset temperature difference threshold, the refrigerator door is controlled to open for heat exchange. The real-time heat exchange of the refrigerator is determined based on the real-time internal temperature of the refrigerator and the ambient temperature. The door is controlled to close when the real-time heat exchange is less than a preset heat exchange threshold.

2. The control method as described in claim 1, characterized in that, The step of controlling the refrigerator door to open for heat exchange based on the initial internal temperature difference between the refrigerator and the ambient temperature being greater than a preset temperature difference threshold includes: Based on the fact that the ambient temperature is between the initial internal temperature and the target temperature, and the temperature difference between the initial internal temperature and the ambient temperature is greater than a preset temperature difference threshold, the refrigerator door is controlled to open for heat exchange.

3. The control method as described in claim 1, characterized in that, The step of determining the real-time heat exchange capacity of the refrigerator based on its real-time internal temperature and the ambient temperature includes: The Prandtl number and Grashof number are determined based on the real-time internal temperature, the ambient temperature, and the air properties. The real-time heat exchange is determined based on the Prandtl number, the Grashof number, and the surface area of ​​the refrigerator liner.

4. The control method as described in claim 3, characterized in that, The determination of Prandtl number and Grashof number based on the real-time internal temperature, the ambient temperature, and air physical properties includes: The Prandtl number is determined based on the dynamic viscosity coefficient, thermal conductivity coefficient, and specific heat capacity at constant pressure among the air physical properties. The Grashof number is determined based on the real-time internal temperature, the ambient temperature, gravitational acceleration, and the coefficient of thermal expansion, heat transfer length, and kinematic viscosity of the air physical properties.

5. The control method as described in claim 3, characterized in that, The step of determining the real-time heat exchange based on the Prandtl number, the Grashof number, and the surface area of ​​the refrigerator liner includes: The real-time heat exchange is determined based on the Prandtl number, the Grashof number, the thermal conductivity, the real-time internal temperature, the ambient temperature, and the surface area of ​​the refrigerator liner.

6. The control method as described in claim 1, characterized in that, Also includes: While controlling the door to open, the fan inside the refrigerator is also turned on for heat exchange.

7. The control method as described in claim 6, characterized in that, The step of determining the real-time heat exchange capacity of the refrigerator based on its real-time internal temperature and the ambient temperature includes: The Prandtl number and Reynolds number are determined based on the real-time internal temperature, the ambient temperature, and the air physical properties. The real-time heat exchange is determined based on the Prandtl number, the Reynolds number, and the surface area of ​​the refrigerator liner.

8. The control method as described in claim 7, characterized in that, The determination of Prandtl number and Reynolds number based on the real-time internal temperature, the ambient temperature, and air physical properties includes: The Prandtl number is determined based on the dynamic viscosity coefficient, thermal conductivity coefficient, and specific heat capacity at constant pressure among the air physical properties. The Reynolds number is determined based on the fluid density, fluid velocity, heat transfer length, and dynamic viscosity coefficient in the air physical properties.

9. The control method as described in claim 8, characterized in that, The determination of the real-time heat exchange based on the Prandtl number, the Reynolds number, and the surface area of ​​the refrigerator liner includes: The current heat exchange is determined based on the Prandtl number, the Reynolds number, the thermal conductivity, the real-time internal temperature, the ambient temperature, and the surface area of ​​the refrigerator liner.

10. The control method as described in claim 1, characterized in that, Before controlling the refrigerator door to open for heat exchange based on the initial internal temperature difference between the refrigerator and the ambient temperature being greater than a preset temperature difference threshold, the method further includes: Confirm that the refrigerator's operating mode has switched from a first mode to a second mode; wherein the first mode includes one of a cooling mode and a heating mode, and the second mode includes the other.

11. A control device for a vehicle-mounted refrigerator, characterized in that, The device includes: The first control module is used to control the refrigerator door to open for heat exchange when the temperature difference between the initial internal temperature of the refrigerator and the ambient temperature is greater than a preset temperature difference threshold. The heat exchange determination module is used to determine the real-time heat exchange of the refrigerator based on the real-time internal temperature of the refrigerator and the ambient temperature. The second control module is used to control the door to close when the real-time heat exchange is less than a preset heat exchange threshold.

12. A vehicle-mounted refrigerator, comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, when the processor runs the computer program, it performs an action to implement the control method as described in any one of claims 1-10.

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