Method for testing droplet nucleus purification capacity of refrigeration appliance

Abstract

The invention discloses a method for testing the droplet nucleus purification capacity of a refrigeration appliance, and belongs to the field of microbial safety. By recording the concentration of droplet nucleuses in a closed compartment of the refrigeration appliance, tedious collection and culture of air biological specimens are not needed, and by analyzing and calculating the droplet nucleus concentration change recorded by testing, the droplet nucleus purification capacity of the refrigeration appliance is determined. The method can be used for evaluating the droplet nucleus removal efficiency of the refrigeration appliance, can be used for evaluating the droplet nucleus removal efficiency of the refrigeration appliance provided with the health assembly with the droplet nucleus purification and removal capability, such as the droplet nucleus purification and removal efficiency of a commercial refrigerator, and has the characteristics of simplicity and rapidness in operation; the device can be used for efficiently testing the droplet nucleus purification and removal efficiency of the refrigeration appliance, and has practical application significance in preventing respiratory tract infection viruses, particularly diseases infected by droplet nucleus, from diffusing through a cold chain.

Description

Technical Field

[0001] The invention belongs to the field of microbial safety, and in particular relates to a method for testing the droplet nucleus purification capability of a refrigeration appliance. Background Art

[0002] Droplet nuclei refer to relatively stable particles formed by proteins, inorganic salts and microorganisms (bacteria, viruses) remaining after droplets produced by people talking, coughing and sneezing migrate in the air and the water on their surface evaporates. Studies have shown that the particle size of droplet nuclei with high virus concentration and strong infectivity is distributed in 1-3μm (the infectivity is related to the amount of virus carried and the depth of entry into the respiratory tract). Such droplet nuclei can spread the virus through direct inhalation and indirect contact. For example, patients carrying the new coronavirus may produce droplets through breathing, talking, coughing, sneezing, etc., and spread the virus to the inside of the refrigeration equipment when operating the refrigeration equipment. The new coronavirus can survive on the surface of plastic, stainless steel and paper in the refrigeration environment for dozens of days and remain infectious. In a frozen environment, the virus can even survive for several months, which will cause the next user of the refrigeration equipment to be infected with the virus through respiratory exposure or contact. Therefore, it is of great significance to control the concentration of droplet nuclei in the refrigeration room.

[0003] In the prior art, a healthy component capable of removing droplet nuclei is generally installed in the closed compartment of the refrigerator to control the concentration of droplet nuclei. The healthy component is a device installed in the refrigerator, which is driven by the air circulation of the air-cooled refrigeration appliance or its own air circulation drive, and can quickly remove droplet nuclei from the closed refrigeration appliance compartment. But on the other hand, in the prior art, the technology for testing the purification ability of equipment used to purify droplet nuclei is very complicated. Conventional purification ability testing methods generally use planktonic bacteria purification ability testing methods. When detecting the removal efficiency of droplet nuclei in the closed refrigeration appliance compartment, it is often necessary to verify the removal efficiency of the healthy component installed in the closed refrigeration appliance compartment through cumbersome air biological specimen cultivation and collection. This testing method leads to low efficiency in testing the removal efficiency of the healthy component, and at the same time will increase the error caused by uncontrollable factors during the test process. Summary of the invention

[0004] In order to solve the problem of low efficiency in testing the removal efficiency of refrigeration appliances using the floating bacteria purification capability test method mentioned above, the purpose of the present invention is to propose a test method for the droplet nucleus purification capability of refrigeration appliances.

[0005] In order to solve the above problems, the present invention is implemented according to the following technical solutions:

[0006] The present invention provides a method for testing the droplet nucleus purification capability of a refrigeration appliance, wherein the refrigeration appliance comprises a closed compartment and a health component connected to the closed compartment, comprising the following steps:

[0007] S1: preparing a saliva simulation liquid, and placing the saliva simulation liquid in an aerosol atomizer; the aerosol atomizer is located in a closed room of the refrigeration appliance;

[0008] S2: starting an aerosol atomizer, which atomizes the saliva simulation liquid into droplet particles, and the droplet particles are evaporated in the closed room of the refrigeration appliance to form droplet core particles;

[0009] S3: using a particle analyzer to continuously sample and detect the droplet nucleus particles in the closed chamber at a first predetermined time to obtain a sampling result, wherein the sampling result is a particle concentration: the particle analyzer has a sampling tube connected to the closed chamber;

[0010] S4: Calculate the removal efficiency of droplet nucleus particles within the second predetermined time according to the sampling result of the particle analyzer.

[0011] Preferably, the saliva simulation solution in step S1 is obtained by dissolving 6 g of trypsin powder in 100 ml of distilled water and letting the solution stand for 1 hour.

[0012] Preferably, the aerosol atomizer generator is a single-nozzle Collison atomizer. In step S2, the atomization parameters of the Collison atomizer are a gas pressure of 0.15-0.3 MPa and an atomization flow rate of 2-3 L / min.

[0013] Preferably, the atomized particle size of the droplet particles is 2-2.5 μm, and the particle size of the droplet core particles is 1-1.5 μm;

[0014] Among them, step S2 is used to form a concentration of 10-15 mg / m 3 of droplet nuclei.

[0015] Preferably, the particle analyzer in step S4 is a gravimetric particle analyzer, the cutting particle size of the particle analyzer is 1.0 μm, and the sampling interval of the sampling tube is 60 seconds;

[0016] Wherein, the first predetermined time is 12 minutes.

[0017] Preferably, according to the sampling result of the particle analyzer, the removal efficiency of the droplet nucleus particles within the second predetermined time is calculated, specifically including:

[0018] From the sampling results, 10 consecutive sampling values ​​are obtained; the 10 consecutive sampling values ​​are particle concentration values ​​sampled every 60 seconds at the end of 10 minutes within the first predetermined time; the 10 sampling values ​​include a time parameter, and the time parameters of the 10 sampling values ​​are from the 1st minute to the 10th minute in sequence;

[0019] According to the particle attenuation equation: Calculate the particle attenuation constant ke;

[0020] Where:

[0021] C t represents the particle concentration value at time t, where time t is the time parameter;

[0022] C0 represents the particle concentration value at the initial moment, the initial moment is the 1st minute, and C0 is the sampling value of the 1st minute;

[0023] ke is the decay constant of particles, which reflects the rate at which the concentration of particles decreases over time. In this patent, its unit is 1 / min, which is determined by curve fitting or linearization of experimental data.

[0024] t is the time from the start of decay to the measurement of C t The time that has passed.

[0025] Preferably, the actual removal efficiency is calculated based on the actual measured particle concentration: P = 1-C 10 / C0 value;

[0026] Based on the ke value and particle attenuation equation Calculate the particle fitting concentrations C1 and C2 when t = 1min and t = 10min. 10 , calculate the fitting removal efficiency P = 1-C for removing droplet nuclei within the second predetermined time 10 / The value of C1;

[0027] Based on the calculated actual removal efficiency and fitted removal efficiency, the purification capacity of the refrigeration appliances in removing droplet nuclei is evaluated and summarized.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] A method for testing the droplet nucleus purification capability of a refrigerating appliance of the present invention, wherein the refrigerating appliance comprises a closed compartment and a health component connected to the closed compartment, comprising the following steps:

[0030] S1: preparing saliva simulation liquid, and placing the saliva simulation liquid in an aerosol atomizer; the aerosol atomizer generator is located in a closed room of the refrigeration appliance; a sampling tube is arranged in the room of the refrigeration appliance, and the sampling tube is connected to a particle analyzer;

[0031] S2: starting an aerosol atomizer, which atomizes the saliva simulation liquid into droplet particles, and the droplet particles are evaporated in the closed room of the refrigeration appliance to form droplet core particles;

[0032] S3: using a particle analyzer to continuously sample and detect the droplet nucleus particles in the closed chamber at a first predetermined time to obtain a sampling result, wherein the sampling result is a particle concentration: the particle analyzer has a sampling tube connected to the closed chamber;

[0033] S4: Calculate the removal efficiency of droplet nucleus particles within the second predetermined time according to the sampling result of the particle analyzer.

[0034] The testing method of the present invention records the concentration of droplet nuclei in the room of a closed refrigeration appliance, and there is no need to carry out tedious collection and cultivation of air biological specimens. It can be used to evaluate the droplet nucleus removal efficiency of refrigeration appliances equipped with healthy components capable of purifying and removing droplet nuclei, such as the droplet nucleus purification and removal efficiency of commercial refrigerators. It has the characteristics of simple and rapid operation, and has practical application significance for preventing the spread of respiratory infectious viruses, especially diseases transmitted through droplet nuclei, through the cold chain.

[0035] The present invention prepares saliva simulation liquid to replace human saliva, thereby ensuring a stable supply of raw materials for generating droplet particles; by arranging a sampling tube connected to a particle analyzer in a compartment of a refrigeration appliance, the particle analyzer can analyze and detect the particle concentration in real time, so that the sampling result is direct, true and reliable; by using an aerosol atomization generator to atomize the saliva simulation liquid into droplet particles, it is ensured that the generated droplet particles are stable and that the subsequent droplet particles are stable after evaporation to form droplet core particles; by using the particle analyzer to continuously sample and detect the droplet core particles in the closed compartment at a first predetermined time, it is ensured that the droplet core particle concentration at the corresponding sampling time node is obtained in real time, and continuous particle concentration data is obtained, which is convenient for subsequent steps to analyze the sampling results; by calculating the removal efficiency of the droplet core particles within the second predetermined time, the ability of the refrigeration appliance equipped with a healthy component to purify the droplet core can be correspondingly analyzed, and the above method can simplify the process standard, avoid the influence of uncontrollable factors on the test, and ultimately improve the test efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The specific embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings, wherein:

[0037] Figure 1 A set of sampling result analysis tables of the present invention;

[0038] Figure 2 The present invention and Figure 1 A set of droplet nucleus concentration decay curves over time corresponding to the tabular data;

[0039] Figure 3 The present invention and Figure 1 Analysis chart of attenuation constant ke corresponding to the table data;

[0040] Figure 4 This is a schematic diagram of an air-cooled freezer used for testing in Example 1 of the present invention;

[0041] Figure 5 is a flow chart of the method of the present invention. DETAILED DESCRIPTION

[0042] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention. The accompanying drawings are only for reference and illustration purposes and do not constitute a limitation on the scope of patent protection of the present invention, because many changes can be made to the present invention without departing from the spirit and scope of the present invention.

[0043] In order to solve the problem of low efficiency in the test of the efficiency of refrigeration appliances in removing droplet nuclei in the prior art test methods for the purification ability of planktonic bacteria, the present invention proposes a test method for the droplet nuclei purification ability of refrigeration appliances. The core of the test method is to record the droplet nuclei concentration in the closed chamber of the refrigeration appliance without the need for tedious air biological specimen collection and cultivation, and the test method can be used to evaluate the droplet nuclei removal efficiency of the refrigeration appliance.

[0044] like Figure 5 A method for testing the droplet nucleus purification capability of a refrigeration appliance is provided, wherein the refrigeration appliance comprises a closed compartment and a healthy component connected to the closed compartment, comprising the following steps:

[0045] S1: prepare saliva simulating liquid, and place the saliva simulating liquid in an aerosol atomizer; the aerosol atomizer is located in a closed room of a refrigeration device;

[0046] S2: Start the aerosol atomizer, which atomizes the saliva simulation liquid into droplet particles. The droplet particles evaporate in the closed room of the refrigeration device to form droplet core particles;

[0047] S3: using a particle analyzer to continuously sample and detect the droplet nucleus particles in the closed chamber at a first predetermined time to obtain a sampling result, which is a particle concentration: the particle analyzer has a sampling tube connected to the closed chamber;

[0048] S4: Calculate the removal efficiency of droplet nucleus particles within the second predetermined time according to the sampling result of the particle analyzer.

[0049] The method of the present invention mainly tests and studies the efficiency of purifying droplet nucleus particles of a refrigeration appliance equipped with a health component. The droplet nucleus particles mainly exist in the air in the form of aerosols. When studying the efficiency of purifying droplet nucleus particles, the droplet nucleus particles can be directly purified without tedious microbial culture. The present invention prepares saliva simulation liquid instead of human saliva to ensure a stable supply of raw materials for producing droplet particles; by arranging a sampling tube connected to a particle analyzer in the room of the refrigeration appliance, the particle analyzer can analyze and detect the particle concentration in real time, so that the sampling result is direct, true and reliable; by using an aerosol atomizer to atomize the saliva simulation liquid into droplet particles, ensuring the stability of generated droplet particles and the stability of droplet nucleus particles formed by subsequent droplet particles after evaporation; by using a particle analyzer to continuously sample and detect the droplet nucleus particles in the closed chamber according to a first predetermined time, it is possible to ensure that the droplet nucleus particle concentration at the corresponding sampling time node is obtained in real time, and continuous particle concentration data is obtained, which is convenient for subsequent steps to analyze the sampling results; by calculating the removal efficiency of droplet nucleus particles within a second predetermined time, the ability of the refrigeration appliance equipped with a healthy component to purify droplet nuclei can be correspondingly analyzed. The above method can simplify the process standards, avoid the influence of uncontrollable factors on the test, and ultimately improve the test efficiency.

[0050] Preferably, the saliva simulation solution in step S1 is obtained by dissolving 6 g of trypsin powder in 100 ml of distilled water and letting the solution stand for 1 hour.

[0051] In this embodiment, trypsin is a commonly used component of microbial culture medium, which is a powdered substance obtained by enzymatic hydrolysis, acidification and drying of animal protein. The saliva simulation liquid prepared in step S1 needs to contain water, protein and inorganic salt components and needs to ensure that its properties such as component ratio, specific gravity, viscosity, surface tension, etc. are similar to those of human saliva. Saliva simulation liquid with properties similar to those of human saliva can be quickly prepared by adding trypsin powder to distilled water. It can be understood that standing for 1 hour is to allow the trypsin powder to fully dissolve in distilled water, and the saliva simulation liquid can be refrigerated for 7 days after synthesis, and can be used when restored to room temperature, which can reduce the consumables of the test and reduce the preparation steps of the test.

[0052] Preferably, the aerosol atomizer generator is a single-nozzle Collison atomizer. In step S2, the atomization parameters of the Collison atomizer are a gas pressure of 0.15-0.3 MPa and an atomization flow rate of 2-3 L / min.

[0053] In this embodiment, for the refrigeration appliance equipped with a health component that needs to be studied, out of the need to simulate the generation of droplets by the human body, a Collison nebulizer that can adjust the airflow and atomization flow rate is selected to control the concentration and particle size distribution of the generated aerosol. It can be understood that the single nozzle design ensures the consistency and repeatability of the atomization process, making the size and distribution of the droplet particles generated by atomization more uniform; out of the need to simulate the exhaled air pressure in situations such as human breathing and sneezing, the gas pressure is maintained at 0.15-0.3MPa to cover the air pressure range of droplets exhaled by the human body under normal circumstances; because the airflow of the nebulizer nozzle needs to produce an aerosol equivalent to the normal amount of droplets exhaled by the human body, the atomization flow rate is set to 2-3L / min to complete the simulation of such situations.

[0054] Preferably, the atomized particle size of the droplet particles is 2-2.5 μm, and the particle size of the droplet core particles is 1-1.5 μm; wherein step S2 is used to form a concentration of 10-15 mg / m 3 of droplet nuclei.

[0055] It is known that when the particle size is less than 1μm, a small number of particles will diffuse to the tracheal wall or alveolar deposition, and most will be exhaled. Droplet nuclei with a particle size distribution of 1-3μm are more likely to spread the virus through direct inhalation and indirect contact. For example, the droplet nuclei exhaled by patients with the new coronavirus often carry high concentrations of the virus and are highly infectious.

[0056] In this embodiment, the atomized particle size of the droplet particles generated by atomization is 2-2.5 μm, and the particle size of the droplet nucleus particles formed by evaporation is 1-1.5 μm, which can simulate the droplet nucleus particles with a higher possibility of virus transmission. The test of the refrigeration appliance under this condition can ensure that the simulated droplet nucleus particles of the droplet nucleus that transmit the virus have a higher probability of virus transmission as much as possible, make the test conditions uniform, and avoid the influence of the droplet nucleus particle size being too large or too small and the particle size span being too large or too small, so that the test results are more objective; it can be understood that the concentration of the droplet nucleus particles in the closed refrigeration appliance room after the atomization operation is completed is 10-15 mg / m 3 It is real scene data simulating the closed compartment of refrigeration equipment.

[0057] Preferably, the particle analyzer in step S4 is a gravimetric particle analyzer, the cutting particle size of the particle analyzer is 1.0 μm, and the sampling interval of the sampling tube is 60 seconds; wherein the first predetermined time is 12 minutes.

[0058] It can be known that the principle of the gravimetric particle analyzer is mainly based on the membrane weighing method. The principle of the membrane weighing method is to sample at a specified flow rate, capture the particles in the air on a high-performance filter membrane, and then weigh the mass of the filter membrane before and after sampling. The mass of the captured dust is obtained by calculating the mass difference. The ratio of this mass to the sampled air volume is the mass concentration of the dust. In this embodiment, the sampling tube is connected to the gravimetric particle analyzer, and the cutting particle size is related to the collection efficiency of the particles. The gravimetric particle analyzer sets the cutting particle size to 1.0 μm. The sampling tube captures the droplet nucleus particles corresponding to the cutting particle size by impact sampling, so that the particle analyzer responds fastest to the particles with a cutting particle size of 1.0 μm, ensuring the representativeness of the collected samples; it can be understood that the sampling interval of the sampling tube is 60s, and the sampling interval of 60s ensures that the particle analyzer has sufficient time resolution to capture short-term changes in the droplet nucleus concentration; continuous sampling for 12 minutes helps to obtain a stable value of the droplet nucleus concentration and reduce accidental errors.

[0059] Preferably, according to the sampling result of the particle analyzer, the removal efficiency of the droplet nucleus particles within the second predetermined time is calculated, specifically including:

[0060] From the sampling results, 10 consecutive sampling values ​​are obtained; the 10 consecutive sampling values ​​are the particle concentration values ​​sampled every 60 seconds at the end of the first predetermined time and 10 minutes; the 10 sampling values ​​include time parameters, and the time parameters of the 10 sampling values ​​are from the 1st minute to the 10th minute in sequence; according to the particle attenuation equation: Calculate the particle attenuation constant ke;

[0061] Where:

[0062] C t represents the particle concentration at time t, which in this patent is the droplet nucleus particle concentration at the time point corresponding to the 1st to 10th consecutive sampling values ​​within the second predetermined time;

[0063] C0 represents the particle concentration at the initial moment, which in this patent is the particle concentration at the time point corresponding to the first sampling value within the second predetermined time;

[0064] ke is the decay constant of particles, which reflects the rate at which the concentration of particles decreases over time. In this patent, its unit is 1 / min, which is determined by curve fitting or linearization of experimental data.

[0065] t is the time from the start of decay to the measurement of C t The time that has passed.

[0066] In this embodiment, continuous sampling is performed for 12 minutes. Using the data of the last 10 minutes of continuous sampling can reduce the impact of possible measurement errors or instantaneous fluctuations at the initial moment on the results, improve the accuracy of the calculation of the attenuation constant ke, and the terminal data can better reflect the attenuation trend of the system in a stable state, which is helpful to obtain a more accurate and reliable attenuation constant ke. In some cases, the particle concentration at the initial moment may be affected by the starting shock, and the terminal data can avoid this influence. On the other hand, after the saliva simulation liquid is atomized into droplets by an aerosol nebulizer, the droplets need time to evaporate into droplet core particles. Taking the last 10 data is equivalent to providing sufficient time for the droplet particles to evaporate and form droplet core particles, so that the test conditions are closer to the real scene and the test results are more reliable.

[0067] Preferably, the actual removal efficiency is calculated based on the actual measured particle concentration: P = 1-C 10 / C0 value;

[0068] Based on the ke value and particle attenuation equation Calculate the particle fitting concentrations C1 and C2 when t = 1min and t = 10min. 10 , calculate the fitting removal efficiency P = 1-C for removing droplet nuclei within the second predetermined time 10 / The value of C1;

[0069] Based on the calculated actual removal efficiency and fitted removal efficiency, the purification capacity of the refrigeration appliances in removing droplet nuclei is evaluated and summarized.

[0070] It is understandable that the purpose of using data fitting calculation to estimate the purification capacity at a specific time point is to avoid data consistency ambiguity caused by direct sampling operation errors and uneven concentration distribution. By comparing the first sampling value obtained at t=1min and the particle concentration at the end of t=10min, the removal efficiency of the healthy component in purifying droplet nuclei under the same test conditions can be more accurately evaluated.

[0071] The working principle of the test method for the droplet nucleus purification ability of a refrigeration appliance of the present invention is as follows:

[0072] The testing method of the present invention records the concentration of droplet nuclei in the closed room of the refrigeration appliance without the need for tedious collection and cultivation of air biological specimens. By analyzing and calculating the changes in the droplet nucleus concentration recorded in the test, the removal efficiency of the refrigeration appliance in purifying droplet nuclei can be evaluated. Furthermore, it can be used to evaluate the droplet nucleus removal efficiency of refrigeration appliances equipped with healthy components capable of purifying and removing droplet nuclei, such as the droplet nucleus purification and removal efficiency of commercial refrigerators. It has the characteristics of simple and rapid operation, and has practical application significance for preventing the spread of respiratory infectious viruses, especially diseases transmitted through droplet nuclei, through the cold chain.

[0073] The present invention prepares saliva simulation liquid to replace human saliva, thereby ensuring a stable supply of raw materials for generating droplet particles; by arranging a sampling tube connected to a particle analyzer in a compartment of a refrigerating appliance, the particle analyzer can analyze and detect the particle concentration in real time, so that the sampling result is direct, true and reliable; by using an aerosol atomization generator to atomize the saliva simulation liquid into droplet particles, the droplets generated by human breathing, coughing and sneezing can be simulated, ensuring the stability of the generated droplet particles and the stability of the droplet core particles formed by subsequent droplet particles after evaporation; by using the particle analyzer to continuously sample and detect the droplet core particles in the closed compartment at a first predetermined time, it can ensure that the droplet core particle concentration at the corresponding sampling time node is obtained in real time, and continuous particle concentration data is obtained, which is convenient for subsequent steps to analyze the sampling results; by calculating the removal efficiency of the droplet core particles within the second predetermined time, the ability of the refrigerating appliance equipped with a healthy component to purify the droplet core can be correspondingly analyzed, and the above method can simplify the process standard, avoid the influence of uncontrollable factors on the test, and ultimately improve the test efficiency.

[0074] Embodiment 1

[0075] This embodiment is a test of the ability of a commercial refrigerator with a small volume compartment space and a large circulating air volume to purify droplet nuclei. The air in the commercial refrigerator is circulated internally, and the hourly air volume of the internal circulation / the volume of the closed compartment of the refrigerator is greater than 50.

[0076] Preparation stage:

[0077] like Figure 4 As shown, a sampling tube 4 and an aerosol generator 1 are arranged in a commercial refrigerator, the sampling tube 4 is connected to a particle analyzer 5, the aerosol generator 1 is connected to a flow meter 2, and the flow meter 2 is connected to a pressure regulator 3; 6 g of trypsin peptone powder is dissolved in 100 ml of distilled water, and the saliva simulation liquid is obtained after standing for 1 hour.

[0078] Atomization stage:

[0079] The atomization parameters of the Collison nebulizer were set to gas pressure of 0.15-0.3 MPa and atomization flow rate of 2-3 L / min, so that the particle size of the droplet particles produced by atomization was 2-2.5 μm and the particle size of the droplet core particles was 1-1.5 μm. The Collison nebulizer was started to atomize the saliva simulation liquid to form a concentration of 10-15 mg / m in the closed room. 3 of droplet nuclei.

[0080] Sampling phase:

[0081] The cutting particle size of the particle analyzer is set to 1.0 μm, the sampling interval of the sampling tube is set to 60 s, and continuous sampling is performed for 12 minutes according to the first preset time to obtain the particle concentration data corresponding to the sampling time point.

[0082] Computational analysis phase:

[0083] According to the sampling results of the particle analyzer, the removal efficiency of the droplet nucleus particles within the second predetermined time is calculated, specifically including:

[0084] From the sampling results, 10 consecutive sampling values ​​are obtained; the 10 consecutive sampling values ​​are the particle concentration values ​​per minute at the end of the first preset time, as follows: Figure 1 Table shows;

[0085] According to the particle attenuation equation like Figure 2-3 It is shown that through linear regression analysis, the attenuation constant is ke = 0.3093;

[0086] The linear regression model was checked for goodness of fit, and its coefficient of determination was R2 = 0.9856, indicating that the fitted estimate of particle concentration was reliable;

[0087] When t = 10min, the removal efficiency of the healthy components installed in the commercial air-cooled refrigerator for removing droplet nuclei is:

[0088] The actual removal efficiency P1 = 94.30%, which can be calculated, and the fitted removal efficiency P2 = 95.46%;

[0089] Conclusion: In the test, the actual efficiency of removing droplet nuclei of this commercial refrigerator was 94.30%, and the fitting efficiency was 95.46%.

[0090] For other structures of the method for testing the droplet nucleus purification capability of a closed refrigeration appliance chamber in this embodiment, refer to the prior art.

[0091] The above are only preferred embodiments of the present invention and are not intended to limit the present invention in any form. Therefore, any modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A method for testing the droplet nucleus purification capability of a refrigeration appliance, wherein the refrigeration appliance comprises a closed compartment and a health component connected to the closed compartment, characterized in that: The following steps are involved: S1: preparing a saliva simulation liquid, and placing the saliva simulation liquid in an aerosol atomizer; the aerosol atomizer is located in a closed room of the refrigeration appliance; S2: starting an aerosol atomizer, which atomizes the saliva simulation liquid into droplet particles, and the droplet particles are evaporated in the closed room of the refrigeration appliance to form droplet core particles; S3: using a particle analyzer to continuously sample and detect the droplet nucleus particles in the closed chamber at a first predetermined time to obtain a sampling result, wherein the sampling result is a particle concentration: the particle analyzer has a sampling tube connected to the closed chamber; S4: Calculate the removal efficiency of droplet nucleus particles within the second predetermined time according to the sampling result of the particle analyzer.

2. The method for testing the droplet nucleus purification capability of a refrigeration appliance according to claim 1, characterized in that: The saliva simulation solution in step S1 is obtained by dissolving 6 g of trypsin powder in 100 ml of distilled water and letting it stand for 1 hour.

3. The method for testing the droplet nucleus purification capability of a refrigeration appliance according to claim 1, characterized in that: The aerosol atomization generator is a single-nozzle Collison atomizer. In step S2, the atomization parameters of the Collison atomizer are a gas pressure of 0.15-0.3 MPa and an atomization flow rate of 2-3 L / min.

4. The method for testing the droplet nucleus purification capability of a refrigeration appliance according to any one of claims 1 to 3, characterized in that: The atomized particle size of the droplet particles is 2-2.5 μm, and the particle size of the droplet core particles is 1-1.5 μm; Wherein, step S2 is used to form droplet nucleus particles with a concentration of 10-15 mg / m3 in a closed room.

5. The method for testing the droplet nucleus purification capability of a refrigeration appliance according to claim 1, characterized in that: The particle analyzer in step S4 is a gravimetric particle analyzer, the cutting particle size of the particle analyzer is 1.0 μm, and the sampling interval of the sampling tube is 60 seconds; Wherein, the first predetermined time is 12 minutes.

6. The method for testing the droplet nucleus purification capability of a refrigeration appliance according to claim 1, characterized in that: According to the sampling results of the particle analyzer, the removal efficiency of the droplet nucleus particles within the second predetermined time is calculated, specifically including: From the sampling results, 10 consecutive sampling values ​​are obtained; the 10 consecutive sampling values ​​are particle concentration values ​​sampled every 60 seconds at the end of 10 minutes within the first predetermined time; the 10 sampling values ​​include a time parameter, and the time parameters of the 10 sampling values ​​are from the 1st minute to the 10th minute in sequence; According to the particle attenuation equation: Calculate the particle attenuation constant ke; Where: C t represents the particle concentration value at time t, where time t is the time parameter; C0 represents the particle concentration value at the initial moment, the initial moment is the 1st minute, and C0 is the sampling value of the 1st minute; ke is the decay constant of particles, which reflects the rate at which the concentration of particles decreases over time. In this patent, its unit is 1 / min, which is determined by curve fitting or linearization of experimental data. t is the time from the start of decay to the measurement of C t The time that has passed.

7. The method for testing the droplet nucleus purification capability of a refrigeration appliance according to claim 6, characterized in that: According to the actual measured particle concentration, calculate the actual removal efficiency P = 1-C 10 / C0 value; Based on the ke value and the particle attenuation equation Calculate the particle fitting concentrations C1 and C2 when t = 1min and t = 10min. 10 , calculate the fitting removal efficiency P = 1-C for removing droplet nuclei within the second predetermined time 10 / The value of C1; Based on the calculated actual removal efficiency and fitted removal efficiency, the purification capacity of the refrigeration appliances in removing droplet nuclei is evaluated and summarized.

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