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CN-121977319-A - Ultrasonic-electric heating coupling defrosting method for cold storage air cooler

CN121977319ACN 121977319 ACN121977319 ACN 121977319ACN-121977319-A

Abstract

The invention discloses an ultrasonic-electric heating coupling defrosting method of a cold storage air cooler, which is characterized in that an ultrasonic defrosting can quickly crush a frost layer structure at the initial stage of defrosting and reduce the subsequent melting heat requirement, and electric heating defrosting provides stable and controllable melting heat to ensure different action mechanisms of complete defrosting of the frost layer to carry out advantage complementation and coupling, and precise on-demand control is applied, namely, the time sequence and power distribution of ultrasonic waves and electric heating are accurately perceived through information fusion of multiple sensors, so that the refined defrosting control aiming at minimum energy consumption and minimum heat interference is finally realized, thereby not only effectively inhibiting the growth of the frost layer, prolonging the defrosting period and reducing the defrosting energy consumption, but also obviously reducing the fluctuation peak value of the heat of the frost layer in the defrosting process, and obviously reducing the residual moisture on the surface of fins and improving the defrosting completeness.

Inventors

  • HUA KAITAI

Assignees

  • 湖南现代物流职业技术学院

Dates

Publication Date
20260505
Application Date
20260317

Claims (10)

  1. 1. The ultrasonic-electric heating coupling defrosting method for the cold storage air cooler comprises an ultrasonic defrosting system, an electric heating defrosting system, a first temperature sensor, a temperature and humidity sensor, a pressure difference sensor and a control system which are arranged on the air cooler, wherein the pressure difference sensor is assembled on an air flow passage of an evaporator of the air cooler, and the method is characterized by comprising the following steps of: S1, in a refrigeration mode, monitoring the fin temperature Tfin of the evaporator through a first temperature sensor, and collecting the temperature and relative humidity data of inlet air of the evaporator through a temperature and humidity sensor when the Tfin is smaller than 0 ℃ so as to calculate the dew point temperature Td of the inlet air of the evaporator; s2, if Tfin is lower than Td, judging that the fin surface of the evaporator enters a soaking and thin frost growing initial stage, starting an ultrasonic defrosting system at the moment, and performing frost suppression by adopting an intermittent working mode; S3, if the difference between delta P and delta P0 exceeds a threshold value, stopping the operation of the ultrasonic defrosting system, starting the electric heating defrosting system to quickly melt the fin frost layer of the evaporator, and starting the ultrasonic defrosting system again after delaying for 2 minutes to accelerate separation of the fin frost layer of the evaporator and ice water, wherein delta P is the instantaneous pressure difference between the front and the rear of the air flowing through the fin array of the evaporator monitored by the pressure difference sensor, and delta P0 is the initial pressure difference or the reference value between the front and the rear of the air flowing through the fin array of the evaporator monitored by the pressure difference sensor when the evaporator is in a clean frostless state; S4, when Tfin is higher than 7 ℃, judging that the fin frost layer of the evaporator is completely melted, and at the same time, stopping the operation of the electric heating defrosting system by the control system; and S5, the ultrasonic defrosting system is operated for 1 minute to remove water drop residues on the fin surfaces of the evaporator.
  2. 2. The method for defrosting a refrigerator cooler by ultrasonic-electric heating coupling according to claim 1, wherein the threshold is 55+ -5 Pa.
  3. 3. The method for defrosting a refrigerator cooler by ultrasonic-electric heating coupling according to claim 1, wherein the intermittent operation mode is at least 2 seconds before at least 1 second.
  4. 4. The method for defrosting a refrigerator cooler by ultrasonic-electric heating coupling according to any one of claims 1-3, wherein the first temperature sensor is a PT100 thermal resistance type temperature sensor and is attached to the fin array of the evaporator.
  5. 5. The method of claim 4, wherein the cooling fan is further provided with a plurality of second temperature sensors, the second temperature sensors are thermocouple type temperature sensors, and the plurality of second temperature sensors are arranged at least at intervals along the length direction of the evaporator at the air inlet of the cooling fan.
  6. 6. The method for defrosting a refrigerator cooler according to claim 5, wherein the plurality of second temperature sensors are disposed at equal intervals from each other.
  7. 7. The method for defrosting a cold air blower of a refrigerator by ultrasonic-electric heating coupling according to any one of claims 1 to 3, wherein the ultrasonic defrosting system comprises an ultrasonic generator and a plurality of ultrasonic transducers matched with the ultrasonic generator, and the ultrasonic transducers are arranged in an array along the air flow direction and are assembled on a copper pipe fixing base positioned in the middle of the cold air blower.
  8. 8. The method for defrosting a refrigerator cooler by ultrasonic-electric heating coupling of claim 7, wherein the ultrasonic transducer is assembled on the vibration plate by screwing and glue bonding, and the vibration plate is assembled on the copper pipe fixing base by screwing and glue bonding.
  9. 9. The ultrasonic-electric heating coupling defrosting method for the cold air blower of the refrigeration house according to any one of claims 1-3 is characterized in that the electric heating defrosting system comprises a first electric heating pipe and a second electric heating pipe, wherein the first electric heating pipe is nested in a fin of the cold air blower, and the second electric heating pipe is assembled on a water receiving disc of the cold air blower.
  10. 10. The method for defrosting a refrigerator cooler according to claim 9, wherein the heating power of the first electric heating pipe is 8.9 kilowatts, and the heating power of the second electric heating pipe is 4.4 kilowatts.

Description

Ultrasonic-electric heating coupling defrosting method for cold storage air cooler Technical Field The invention relates to the technical field of defrosting of air coolers, in particular to an ultrasonic-electric heating coupling defrosting method of a refrigeration house air cooler. Background With the rapid development of the cold chain logistics industry, a cold storage is used as a core infrastructure of the cold chain logistics, and an air cooler with a fin tube evaporator as a core is often adopted to realize heat exchange. In the operation process of the air cooler, a single mode is mostly adopted for defrosting, such as electric heating defrosting or ultrasonic defrosting, but when the air cooler is operated in a low-temperature high-humidity environment, the frosting on the surface of the evaporator of the air cooler can lead to the problems of heat transfer deterioration, wind resistance rapid increase, temperature runaway and the like, which can cause the energy efficiency reduction of a refrigerating system, so the current single defrosting mode cannot effectively defrost, and has the following defects: 1. The energy consumption of electric heating defrosting is high, and a large amount of heat is absorbed by the evaporator body, so that the fluctuation of the warehouse temperature is severe. 2. The ultrasonic defrosting utilizes high-frequency mechanical vibration energy to effectively shake and strip frost crystals, has obvious effect on loose frost layers, has extremely low energy consumption and almost generates no extra heat, but has insufficient capability of removing frost layers clung to a substrate or melted residual water drops, namely a defrosting dead zone exists. Disclosure of Invention Therefore, the invention aims to solve the problems, and provides the ultrasonic-electric heating coupling defrosting method for the cold air cooler of the refrigerator, which not only can effectively inhibit the growth of a frost layer, prolong the defrosting period and reduce the defrosting energy consumption, but also can obviously reduce the peak value of the fluctuation of the temperature of the refrigerator in the defrosting process, and simultaneously obviously reduce the residual moisture on the surface of the fins and improve the defrosting completeness. In order to achieve the above purpose, the technical scheme provided by the invention is as follows: The invention provides an ultrasonic-electric heating coupling defrosting method of a cold storage air cooler, which comprises an ultrasonic defrosting system, an electric heating defrosting system, a first temperature sensor, a temperature and humidity sensor, a pressure difference sensor and a control system which are arranged on the air cooler, wherein the pressure difference sensor is assembled on an air flow passage of an evaporator of the air cooler, and comprises the following steps of: s1, the method comprises the steps of (1), in the cooling mode, the fin temperature Tfin of the evaporator is monitored by the first temperature sensor, and when Tfin is less than 0 degrees celsius, acquiring temperature and relative humidity data of inlet air of the evaporator through a temperature and humidity sensor so as to calculate dew point temperature Td of the inlet air of the evaporator; s2, if Tmin is lower than Td, the fin surface of the evaporator is judged to enter the initial stage of soaking and frost growth, at this time, an ultrasonic defrosting system is started, and adopting an intermittent working mode to inhibit frost; s3, if the difference between the delta P and the delta P0 exceeds the threshold value, the control system stops the ultrasonic defrosting system to continue to operate and starts the electric heating defrosting system to quickly melt the fin frost layer of the evaporator; and after the delay time is 2 minutes, the ultrasonic defrosting system is started again, to accelerate the separation of the fin frost layer and ice water of the evaporator; wherein ΔP is the instantaneous pressure difference of the air before and after flowing through the fin array of the evaporator monitored by the pressure difference sensor; Δp0 is the initial pressure difference or baseline value before and after the pressure difference sensor monitors the air flow across the fin array of the evaporator during a clean frostless condition; s4, when Tmin is higher than 7 ℃, judging that the fin frost layer of the evaporator is completely melted, and at the same time, stopping the operation of the electric heating defrosting system by the control system; and S5, the ultrasonic defrosting system is operated for 1 minute to remove water drop residues on the fin surfaces of the evaporator. Further, the threshold is 55.+ -.5 Pa. Further, the intermittent operation mode is to operate for at least 2 seconds before intermittent operation for at least 1 second. Further, the first temperature sensor is a PT100 thermal resistance type temperature sensor a