The refrigeration function of the cake cabinet is based on the thermodynamic refrigeration principle, and a low temperature environment is achieved through a mechanical refrigeration system. Good refrigeration function is the key to ensuring food health. Temperature can be precisely controlled in the display cabinets of cake cabinets, food stores, and dessert shops.
Core technologies can be divided into the following five levels:
First, the refrigeration cycle system (core principle)
A refrigeration cycle system is a system used to achieve cooling effect. It transfers heat from one place to another through a series of physical processes, thereby reducing the temperature of a specific area.
compression process
The compressor compresses the refrigerant (e.g. R404A or R134a) into a high-temperature and high-pressure gas, converting electrical energy into heat, and the temperature at this stage can reach 80-100 degrees Celsius.
Condensation heat dissipation
The high-temperature gas is exchanged with the outside air through the condenser (fin heat exchanger), and the heat is released and liquefied. At this stage, the pressure is about 1.2-1 MPa, and the temperature is reduced to 30-40 ° C.
expansion depressurization
The liquid refrigerant is throttled by the expansion valve, the pressure drops sharply to 0.15-0 MPa, and the liquid part flashes into a gaseous state, absorbing a lot of latent heat.
Endothermic evaporation
The low-temperature and low-pressure refrigerant boils and vaporizes in the evaporator (coil or fin) to absorb the heat of the cabinet (2-8 ° C) to achieve the cooling effect.
Ⅱ.Temperature control technology
Temperature control technology is a method and means for regulating and maintaining a specific temperature range. It can monitor, adjust and control temperature through various devices and systems, such as thermostats, cooling systems, heating systems, etc
PID temperature control system
The temperature in the cabinet is monitored in real time by a high-precision temperature sensor (with an accuracy of ± 0.5 ° C), and the compressor start-stop frequency is dynamically adjusted by a proportional integration and differentiation algorithm to ensure that the temperature fluctuation is less than or equal to ± 1 ° C.
Intelligent defrosting technology
When the frost thickness of the evaporator reaches 1.5-2 mm, it is automatically defrosted through an electric heating wire or a hot gas bypass valve to maintain the heat exchange efficiency.
III. Airflow organization design
Airflow organization design refers to the planning and design of the direction, velocity, and distribution of air flow in a certain space.
Air-cooled circulation system
The centrifugal fan is used to force the circulation of cold air, and the wind speed is controlled at 2-3m/s to ensure temperature uniformity (temperature difference ≤ 2 ° C). The typical model has 30-50 air changes per hour.
Direct cooling moisturizing system
The evaporator directly contacts the cabinet and is cooled by natural convection, maintaining a humidity of 60-70% RH, suitable for moisturizing cream cakes.
IV. Thermal insulation structure optimization
"Thermal insulation structure optimization" refers to the improvement and improvement of the structure that plays a role in thermal insulation. This may include the selection of thermal insulation materials, the adjustment of the thickness of the thermal insulation layer, and the design improvement of the thermal insulation structure to improve the thermal insulation effect, reduce energy consumption, and enhance the stability and durability of the structure.
Polyurethane foam layer
The cabinet is made of high-density polyurethane with a thickness of ≥ 50mm (thermal conductivity 0.022W/m · K), and with a vacuum insulation panel (VIP), the thermal resistance can reach 4.0 (m ² · K)/W.
Low Emission Glass Door
Three-layer hollow Low-E glass (shading coefficient ≤ 0.25), combined with electric heating wire to prevent condensation, reduce external heat radiation.
V. Additional functional modules
"Additional function module" usually refers to a set of functions provided in a system or software in addition to the basic functions.
Humidity compensation system
Linkage through ultrasonic humidifier or humidity sensor to maintain stable humidity in the cabinet and prevent the cake from drying and cracking.
UV sterilization module
Built-in UV-C lamp with a wavelength of 254nm, the air treatment capacity per cubic meter is ≥ 0.5m ³/h, and microorganisms such as mold are killed.
Through the combination of the above technologies, modern cake cabinets can achieve the triple goals of accurate temperature control, high efficiency and energy conservation, and food preservation. When purchasing, it is recommended to pay attention to core indicators such as cooling capacity (unit kW/m ³), noise value (≤ 55dB) and intelligence (such as remote monitoring interface).
