Automatic shell-making wire environment simulation system

Abstract

The invention discloses an automatic shell-making wire environment simulation system. The system comprises an environmental parameter testing unit, a heat and mass transfer model establishing unit and an optimization processing unit. The environmental parameter testing unit is used for testing environmental parameters influencing the drying process of the shell-making drying cabin through testing equipment, evaluating the uniformity of airflow in the drying cabin and the change condition of the environmental parameters, and sending testing and evaluating results to the heat and mass transfer model establishing unit; the environmental parameters at least comprise wind speed. And the heat and mass transfer model building unit is used for building a shell drying heat transfer model and a shell drying mass transfer model, evaluating the shell drying heat transfer model and the shell drying mass transfer model based on the model expression indexes after building is completed, and analyzing the influence of the environmental parameters on shell heat transfer and mass transfer based on the information transmitted by the environmental parameter testing unit. And the optimization processing unit is used for introducing the influence of load, airflow in the drying cabin and air into the established shell drying heat transfer model and shell drying mass transfer model for simulation and optimization.

Description

Technical Field

[0001] This application relates to the field of environmental simulation technology, and in particular to an automated shell-making line environmental simulation system. Background Technology

[0002] Investment casting, as a special casting method, can cast complex parts with special shapes and materials while ensuring high precision. In aerospace manufacturing, engines, as key equipment, rely heavily on investment casting for components such as casings and blades. With the development of my country's aerospace industry and the acceleration of industrialization, various investment casting processes have developed rapidly, especially the aerospace and energy power industries, which have driven the expansion of high-value-added investment casting production. The precision casting process generally includes investment pattern making, shell making, baking, melting, pouring, and cleaning. The coating shell making process involves applying a suitable coating to a wax pattern and then sprinkling sand to form the shell. To ensure sufficient strength, the coating layer (referred to as coating) is usually required to be 4 to 7 layers. The most important step in the coating shell making process is shell drying, and the drying rate has a significant impact on the yield. Furthermore, since the moisture dissipation rate during the shell drying process depends not only on the properties of the coating itself but also on the ambient air temperature, relative humidity, and wind speed, the environmental parameters inside the drying chamber have a significant impact on the coating shell making process. Therefore, in order to ensure the strength and quality of the shell, the coating drying process needs to be controlled within a suitable temperature and humidity range.

[0003] In China, investment casting plants commonly use air conditioning and dehumidifiers to control indoor temperature and humidity. However, experiments have shown that wind speed and air humidity within the drying chamber affect the evaporation rate of moisture in the silica sol, thus impacting the shell drying efficiency. Furthermore, properly arranging fans to ensure sufficient and uniform airflow within the coating shell drying chamber is crucial for improving the drying quality and speed of silica sol shells.

[0004] However, in traditional drying models, wind speed is usually simplified to a fixed constant, or wind speed variation is not considered. This causes the simulation effect of the drying process to deviate significantly in environments with unstable or highly variable wind speeds, resulting in unsatisfactory drying effects in actual operation. Summary of the Invention

[0005] To address the aforementioned issues, this application provides an automated shell-making line environment simulation system. The aim is to improve the simulation effect of the drying process and avoid significant deviations in the simulation effect of the drying process under conditions of unstable or highly variable wind speeds, which could lead to unsatisfactory drying results in actual operation.

[0006] The embodiments of this application disclose the following technical solutions:

[0007] This application provides an automated shell-making line environment simulation system, the system comprising: an environmental parameter testing unit, a heat and mass transfer model establishment unit, and an optimization processing unit; the environmental parameter testing unit and the optimization processing unit are both connected to the heat and mass transfer model establishment unit.

[0008] The environmental parameter testing unit is used to test the environmental parameters affecting the drying process of the shell-making drying chamber using testing equipment, and to evaluate the uniformity of airflow in the drying chamber and the changes in the environmental parameters. The test and evaluation results are then sent to the heat and mass transfer model establishment unit. The environmental parameters include at least wind speed.

[0009] The heat and mass transfer model establishment unit is used to establish a shell drying heat transfer model and a shell drying mass transfer model. After the model is established, the shell drying heat transfer model and the shell drying mass transfer model are evaluated based on the model performance index, and the influence of environmental parameters on shell heat transfer and mass transfer is analyzed based on the information transmitted by the environmental parameter testing unit.

[0010] The optimization processing unit is used to simulate and optimize the effects of load, airflow in the drying chamber, and air in the established shell drying heat transfer model and shell drying mass transfer model.

[0011] In an optional implementation, the heat and mass transfer model establishment unit is further used to optimize the established model by introducing the influence factors of environmental heat transfer and the non-uniformity of the coating layer during the process of establishing the shell drying heat transfer model and the shell drying mass transfer model.

[0012] In an optional implementation, the optimization processing unit specifically includes: an air handling module, a load calculation module, and an airflow analysis module;

[0013] The air treatment module is used to simulate and optimize the interaction between air and the shell during the drying process, and to treat the air before it enters the drying chamber.

[0014] The load calculation module is used to monitor real-time data during the drying process, dynamically adjust the parameters of the air conditioning system, and thus obtain the required cooling load and humidity load.

[0015] The airflow analysis module is used to simulate and optimize the distribution of airflow on and around the surface of the shell, and to analyze the impact of airflow on heat transfer and mass transfer during the drying process.

[0016] In an optional implementation, the air handling module processes the air before it enters the drying chamber, specifically including: return air diversion and pretreatment, air cooling and dehumidification, air mixing and treatment in the mixing box, humidification and heating, and adjustment of air volume and speed.

[0017] In an optional implementation, the cooling load obtained by the load calculation unit includes: external wall cooling load, equipment cooling load, outdoor wind intrusion cooling load, shell latent heat cooling load, and shell sensible heat cooling load;

[0018] The wet load obtained by the load calculation unit includes: shell moisture dissipation and outdoor intrusion wet load.

[0019] In an optional implementation, the formula for calculating the external wall cooling load is:

[0020] ;

[0021] in, The external wall cooling load; Calculate the area of ​​the building envelope; The dry-bulb temperature of the air inside the factory building; This refers to the dry bulb temperature inside the drying chamber. The heat transfer coefficient of the building envelope is calculated using the following formula:

[0022] ;

[0023] in, The thickness of each layer of material; The thermal conductivity of each layer of material;

[0024] The formula for calculating the cooling load of the equipment is as follows:

[0025] ;

[0026] in, The cooling load generated by the heat generated by the equipment; The number of fans inside the drying chamber; The fan opening degree inside the drying chamber; The operating power of a single fan; This is the power factor of the fan;

[0027] The formula for calculating the outdoor wind intrusion cooling load is as follows:

[0028] ;

[0029] in, This is due to the intrusion of outdoor wind into the cooling load. This refers to the air intake volume of the automatic door. The enthalpy value of the air outside the drying chamber; This refers to the enthalpy value inside the drying chamber;

[0030] The formula for calculating the latent heat cooling load of the shell is:

[0031] ;

[0032] in, The latent heat cooling load is generated by moisture dissipation from the shell. It is the heat of condensation; This refers to the quality loss rate;

[0033] The formula for calculating the sensible heat cooling load of the shell is as follows:

[0034] ;

[0035] in, The sensible heat and cold load of the shell; The heat capacity of the coating; This is the weight of the paint; This is the temperature difference between the paint and the indoor temperature.

[0036] The formula for calculating the moisture dissipation of the shell is as follows:

[0037] ;

[0038] in, This refers to the moisture dissipation of the shell. The number of fully loaded shells inside the dry chamber; This is the weight of the shell before drying; This is the weight of the shell after drying; Drying time;

[0039] The formula for calculating the outdoor intrusive moisture load is as follows:

[0040] ;

[0041] in, Outdoor intrusion moisture load; The amount of air that enters when the outer door is opened; This refers to the moisture content of the air outside the drying chamber. This refers to the humidity content of the air inside the drying chamber.

[0042] In an optional implementation, the expression for the shell drying heat transfer model is:

[0043] ;

[0044] in, Heat transfer per unit time; The latent heat of vaporization of water is taken as 2448.6 kJ / kg; The heat capacity of the coating; This is the weight of the paint; This is the temperature difference between the paint and the indoor temperature. For the mass loss rate, the calculation relationship is shown in the expression of the shell drying mass transfer model described below:

[0045] ;

[0046] in, For moisture content; The mass transfer factor is related to wind speed; To maintain the coating temperature The saturated vapor pressure below; The ambient vapor pressure; This refers to the amount of sand applied. The density of the coating; The thickness of the coating; the expression for the amount of sand applied (m) is:

[0047] ;

[0048] in, Let be the surface area of ​​the shell.

[0049] In an optional implementation, the heat and mass transfer model building unit optimizes the established model by incorporating the influence of ambient heat transfer and the non-uniformity of the coating layer. The expression for the optimized shell drying heat transfer model is as follows:

[0050] ;

[0051] Among them, among them, Heat transfer per unit time; The latent heat of vaporization of water is taken as 2448.6 kJ / kg; The heat capacity of the coating; This is the weight of the paint; This is the temperature difference between the paint and the indoor temperature. This refers to the quality loss rate; Additional heat transfer caused by environmental factors;

[0052] The optimized formula for the shell drying mass transfer model is expressed as follows:

[0053] ;

[0054] in, For moisture content; The mass transfer factor is related to wind speed; To maintain the coating temperature The saturated vapor pressure below; The ambient vapor pressure; This refers to the amount of sand applied. The density of the coating; The thickness of the coating; This is a correction factor; The surface area of ​​the shell; This refers to wind speed.

[0055] In an optional implementation, the environmental parameter testing unit is specifically used to evaluate the uniformity of airflow within the drying chamber and the variation of the environmental parameters through standard deviation and coefficient of variation; wherein, the formula for calculating the standard deviation is:

[0056] ;

[0057] in, The standard deviation; For the first The measured wind speed at each sampling data point; The average wind speed across all sampled data points; This represents the total number of wind speed sampling data points; ;

[0058] ;

[0059] in, is the coefficient of variation.

[0060] In an optional implementation, the model performance index includes one or more of the following: coefficient of determination, mean square error, and root mean square error.

[0061] Compared with the prior art, this application has the following beneficial effects:

[0062] The automated shell-making line environmental simulation system provided in this application includes an environmental parameter testing unit, a heat and mass transfer model establishment unit, and an optimization processing unit. The environmental parameter testing unit tests and evaluates environmental parameters, including wind speed, and feeds this data back to the heat and mass transfer model establishment unit. This helps the heat and mass transfer model establishment unit to build a dual model that fully considers wind speed variations: a shell drying heat transfer model and a shell drying mass transfer model. The shell drying heat transfer model characterizes the heat transferred through the shell during the drying process, while the shell drying mass transfer model describes the process of moisture evaporating from the coating through the surface into the air. Both models are related to environmental parameters such as wind speed and take into account wind speed variations. Therefore, in environments with unstable or highly variable wind speeds, the simulation effect is more realistic than existing drying simulation schemes, avoiding significant deviations and thus contributing to achieving more ideal drying results in actual operation. Furthermore, in the automated shell-making line environmental simulation system, the optimization processing unit further incorporates the effects of load, airflow within the drying chamber, and air into the established shell drying heat transfer and mass transfer models to simulate and optimize these two models. This makes the simulation results more realistic and accurate, thus helping to guide the control of the shell drying process under suitable temperature, humidity, and wind speed. Attached Figure Description

[0063] To more clearly illustrate the technical solutions in the embodiments of this application 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 this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0064] Figure 1 This is a schematic diagram of the structure of an automated shell-making line environment simulation system provided in an embodiment of this application;

[0065] Figure 2 A schematic diagram of the structure of an optimization processing unit in an automated shell-making line environment simulation system provided in this application embodiment;

[0066] Figure 3 This is a schematic diagram illustrating the data flow between components in an automated shell-making line environment simulation system provided in an embodiment of this application. Detailed Implementation

[0067] In the shell-making process of investment casting, a coating shell-making process is required to apply coating to the wax model to form the shell. The drying step in this process places high demands on the environmental parameters. While drying models can simulate the drying process, existing models often fail to account for wind speed, typically simplifying it to a constant or ignoring it altogether. This results in inaccurate simulations under conditions of unstable or highly variable wind speeds. Consequently, the parameters used in the simulation are not ideal when applied to controlling the actual drying process.

[0068] After research, the inventors proposed an automated shell-making line environment simulation system, such as... Figure 1 The structure of the automated shell-making line environmental simulation system shown is configured with an environmental parameter testing unit 10, a heat and mass transfer model establishment unit 20, and an optimization processing unit 30. The environmental parameter testing unit 10 considers changes in environmental parameters such as wind speed and feeds this information back to the heat and mass transfer model establishment unit 20, enabling the latter to fully analyze and study the impact of environmental parameters and their changes on the constructed shell drying heat and mass transfer models. The optimization processing unit 30 introduces the effects of load, airflow within the drying chamber, and air into the two constructed models, allowing the optimized shell drying heat and mass transfer models to achieve more realistic and accurate simulation results by considering more influencing factors. This, in turn, guides the shell drying process to be completed under suitable humidity, temperature, and wind speed.

[0069] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0070] Combination Figure 1 The automated shell-making line environmental simulation system includes an environmental parameter testing unit, a heat and mass transfer model establishment unit, and an optimization unit. Both the environmental parameter testing unit and the optimization unit are connected to the heat and mass transfer model establishment unit.

[0071] The environmental parameter testing unit is used to test the environmental parameters that affect the drying process of the shell-making drying chamber through testing equipment, and to evaluate the uniformity of airflow and the changes in environmental parameters in the drying chamber. The test and evaluation results are sent to the heat and mass transfer model building unit. The environmental parameters include at least wind speed.

[0072] The heat and mass transfer model establishment unit is used to establish the shell drying heat transfer model and the shell drying mass transfer model. After the model is established, the shell drying heat transfer model and the shell drying mass transfer model are evaluated based on the model performance index. The influence of environmental parameters on shell heat transfer and mass transfer is analyzed based on the information transmitted by the environmental parameter testing unit.

[0073] The optimization processing unit is used to simulate and optimize the effects of load, airflow in the drying chamber, and air in the established shell drying heat transfer model and shell drying mass transfer model.

[0074] The environmental parameter testing unit uses testing equipment to test environmental parameters, primarily temperature, humidity, and wind speed. For example, the testing equipment includes an anemometer and a temperature and humidity meter.

[0075] The following two anemometers can be selected:

[0076] Anemometer: MHZ-H30J, measuring range 0.00~30m / s, accuracy ±3% of reading value, resolution 0.01m / s, can simultaneously measure temperature and relative humidity.

[0077] Anemometer: Kestrel NK5500, measuring range 0.6~40m / s, accuracy ±3% of reading, resolution 0.1m / s.

[0078] The two anemometers have different measurement ranges. The MHZ-H30J has a lower lower limit and the Kestrel NK5500 has a higher upper limit, thus enabling a wider range of wind speed testing capabilities.

[0079] The temperature and humidity tester that can be selected is: HOBO UX100-011A, with a range of 1~90%RH, -20~70℃, and an accuracy of ±2%RH, ±0.21℃.

[0080] When assessing the distribution of temperature, humidity, and air velocity within a drying chamber, the effects of different airflow organization designs can be compared by calculating the average temperature and humidity, air velocity, standard deviation (SD), and coefficient of variation (CV). Statistical measurements such as SD and CV can be used to evaluate the uniformity of indoor airflow. CV describes the distribution of a dataset relative to its mean. A lower CV value indicates less variation and better uniformity; a higher CV value indicates greater variation and lower uniformity. Therefore, lower values ​​are considered desirable.

[0081] The formula for calculating the standard deviation (SD) is:

[0082] ;

[0083] in, For the first The measured wind speed at each sampling data point; The average wind speed across all sampled data points; This represents the total number of wind speed sampling data points; .

[0084] The formula for calculating the coefficient of variation (CV) is:

[0085] .

[0086] Furthermore, when assessing the changes in environmental parameters such as temperature, humidity, and wind speed within the drying chamber over time, statistical measurement methods such as standard deviation (SD) and coefficient of variation (CV) can be used for evaluation. A lower CV value indicates less variation and better environmental maintenance within the drying chamber; a higher CV value indicates greater variation and poorer environmental maintenance. Therefore, a lower CV value is considered desirable. Additionally, the percentage of data points where environmental parameters within the drying chamber fall within the design range over a specific time period can be statistically analyzed to evaluate the quality of the environmental control system design.

[0087] The environmental parameter testing unit assesses the uniformity of airflow and the variation of environmental parameters within the drying chamber using standard deviation and coefficient of variation. The assessment results can be further fed back to the heat and mass transfer model building unit, allowing the heat and mass transfer model building unit to better analyze the correlation between environmental parameters, including wind speed, and the model, and to analyze the impact of environmental parameters on shell heat and mass transfer.

[0088] In this embodiment, the heat and mass transfer model building unit constructs a shell drying heat transfer model and a shell drying mass transfer model. The expressions for the two models are described below.

[0089] The expression for the shell drying heat transfer model is:

[0090] ;

[0091] in, This refers to the heat transfer per unit time, representing the heat passing through the mold shell during the drying process. It is generated by the heat transfer process and can be understood as the heating process. The latent heat of vaporization of water is taken as 2448.6 kJ / kg; The heat capacity of the coating; This is the weight of the paint; This is the temperature difference between the paint and the indoor temperature. This refers to the quality loss rate.

[0092] In the expression for the heat transfer model of the above-mentioned shell drying process, it is shown that there are two sources of heat during the drying process: first, the evaporation of water carries away heat, resulting in a mass loss of moisture inside the shell; second, the relationship between the coating temperature change (temperature increase) and its specific heat capacity, representing the heat change during the heating process. As a mass loss rate, it also exists in the shell drying mass transfer model, as shown in the calculation relationship illustrated in the expression of the shell drying mass transfer model below:

[0093] ;

[0094] in, For moisture content; The surface area of ​​the shell; The mass transfer factor is related to wind speed; To maintain the coating temperature The saturated vapor pressure below; This refers to the ambient vapor pressure.

[0095] The expression for the shell drying mass transfer model described above describes the process of moisture evaporating from the coating through the surface into the air. The evaporation rate is proportional to the shell surface area, the mass transfer coefficient related to wind speed, and the difference between the saturated vapor pressure at temperature and the ambient vapor pressure.

[0096] The expression for the amount of sand applied, m, is:

[0097] ;

[0098] The density of the coating; Let be the thickness of the coating. Substituting the shell surface area into the expression for the shell drying mass transfer model introduced above, the expression can be integrated as follows:

[0099] ;

[0100] This formula combines the weight, density, and thickness of the coating with the mass transfer process, further describing the evaporation rate of moisture during the shell drying process. By combining these parameters, the changes in the drying process under different conditions (such as the properties of the coating, environmental parameters such as wind speed, temperature, etc.) can be simulated, thereby optimizing and adjusting the drying process.

[0101] In practical applications, the expression of the shell drying mass transfer model can be substituted into the expression of the shell drying heat transfer model for calculation, thus establishing the relationship between the relevant parameters in the shell drying mass transfer model and the relevant parameters in the shell drying heat transfer model.

[0102] In the optional implementation, the heat and mass transfer model building unit optimizes the established models by introducing the influence factors of ambient heat transfer and coating layer non-uniformity during the establishment of the shell drying heat transfer model and shell drying mass transfer model. Specifically, ambient heat transfer is used to optimize the shell drying heat transfer model, and the influence factor of coating layer non-uniformity is used to optimize the shell drying mass transfer model.

[0103] The heat and mass transfer model building unit optimizes the shell drying heat transfer model, and the expression of the optimized shell drying heat transfer model is as follows:

[0104] ;

[0105] Among them, among them, Heat transfer per unit time; The latent heat of vaporization of water is taken as 2448.6 kJ / kg; The heat capacity of the coating; This is the weight of the paint; This is the temperature difference between the paint and the indoor temperature. This refers to the quality loss rate.

[0106] Additional heat transfer caused by environmental factors can include the influence of external factors such as temperature and humidity on the heat transfer process. In real-world environments, the drying process is affected not only by internal heat sources but also by external temperature and humidity. Therefore, an environmental heat transfer term is introduced. This makes the drying process more closely resemble reality. Actual ambient temperature and humidity often significantly impact the drying process, especially when the drying chamber temperature is not constant or is affected by external climate. By considering these environmental factors, the model can more accurately predict heat changes during the drying process, providing a more precise basis for adjustments, improving drying efficiency, and reducing energy consumption.

[0107] The heat and mass transfer model building unit optimizes the shell drying mass transfer model, and the expression of the optimized shell drying mass transfer model is as follows:

[0108] ;

[0109] in, For moisture content; The mass transfer factor is related to wind speed; To maintain the coating temperature The saturated vapor pressure below; The ambient vapor pressure; This refers to the amount of sand applied. The density of the coating; The thickness of the coating; The surface area of ​​the shell; This refers to wind speed. This is a correction factor used to adjust the effect of wind speed on the evaporation rate, taking into account the non-uniformity of airflow.

[0110] The non-uniformity of the coating and the non-uniformity of the airflow are complementaryly expressed in the model through parameter input and explicit correction, respectively. The non-uniformity of the coating is discretized into parameter space input ( Model optimization is achieved through the physical coupling of H) and the correction coefficient β. H) solves structural non-uniformity and compensates for coating-airflow interaction effect.

[0111] The optimized shell drying mass transfer model considers the impact of wind speed variations on the mass transfer rate. Higher wind speeds increase the moisture evaporation rate and improve the drying effect, while lower wind speeds may lead to insufficient evaporation and prolong the drying time. This is achieved by introducing... This correction allows the model to take into account airflow variations in actual dry environments and dynamically adjust the moisture evaporation rate, thus providing more accurate predictions of the drying process. This is especially true in environments with unstable or highly variable wind speeds, where it effectively improves simulation accuracy.

[0112] In an optional implementation, the heat and mass transfer model building unit in the automated shell-forming line environment simulation system provided in this application embodiment can evaluate the model based on the model performance index after the two models are built. The model performance index can be selected according to actual needs. For example, the model performance index may include one or more of the following: coefficient of determination, mean square error, and root mean square error.

[0113] The coefficient of determination (COD) is a metric that measures the goodness of fit of a regression model. It represents the correlation between the model's predicted values ​​and the actual observed values. The COD ranges from 0 to 1, with values ​​closer to 1 indicating a better model fit.

[0114] Mean squared error is the average squared value that measures the difference between the predicted value and the actual value. The smaller the value, the smaller the error in the model prediction.

[0115] The root mean square error (RMSE) is the square root of the mean square error, and it retains the same units as the original data. RMSE directly reflects the model's prediction error; the smaller the RMSE, the more accurate the model.

[0116] In summary, the above model performance indices can reflect the prediction bias of the models. Therefore, based on the respective model performance indices of the shell drying heat transfer model and the shell drying mass transfer model, we can analyze and determine whether the current corresponding models have achieved the expected prediction results and whether further adjustments and optimizations are needed.

[0117] The shell drying heat transfer model and shell drying mass transfer model constructed in the embodiments of this application can analyze the influence of different environmental parameters (such as temperature, humidity, wind speed, etc.) on the drying efficiency during the drying process, thereby optimizing the shell drying process and ensuring better drying quality and drying efficiency.

[0118] The following section analyzes and introduces the effects of environmental parameters such as temperature, humidity, and wind speed on the heat transfer and mass transfer processes.

[0119] For the heat transfer process:

[0120] Temperature is the primary driver of heat transfer. As the temperature inside the environmental chamber rises, the temperature difference between the shell surface and the surrounding air increases, leading to a corresponding increase in the heat transfer rate. This means the heat exchange rate of the shell accelerates. Air humidity has a relatively indirect effect on heat transfer. While increased humidity slightly improves the thermal conductivity of the air, its overall impact on the heat transfer rate is small. Increased wind speed enhances convective heat transfer, thereby increasing the heat transfer rate on the shell surface. At high wind speeds, the temperature gradient between the shell and the air increases, significantly improving heat transfer efficiency.

[0121] For mass transfer processes:

[0122] Temperature also affects the diffusion rate of matter. As temperature increases, molecular motion intensifies, accelerating mass transfer between the inside and outside of the shell. For example, higher temperatures allow moisture inside the shell to diffuse more easily outwards. Humidity significantly affects the evaporation and absorption rates of moisture within the shell. When ambient humidity is low, moisture inside the shell evaporates more easily, thus enhancing the mass transfer process; conversely, when humidity is high, the evaporation rate of moisture on the shell surface decreases, slowing down the mass transfer rate. Wind speed also affects the evaporation rate. Higher wind speeds accelerate the removal of moisture, increasing the mass transfer rate; at low wind speeds, moisture remains on the shell surface, reducing the mass transfer rate.

[0123] It is evident that feeding back the environmental parameters obtained by the environmental parameter testing unit through testing equipment, along with the evaluated airflow uniformity and environmental parameter variations within the drying chamber, to the heat and mass transfer model building unit, and having the heat and mass transfer model building unit analyze the impact of environmental parameters on shell heat and mass transfer, plays a significant role in constructing and optimizing shell drying heat and mass transfer models. This allows the models to more accurately predict heat changes and material diffusion rates during the drying process. Consequently, the established models can provide a more accurate basis for adjusting environmental parameters and optimizing drying quality and efficiency, especially in environments with unstable or highly variable wind speeds, significantly improving the accuracy and effectiveness of environmental simulation.

[0124] Figure 2This is a schematic diagram of the structure of an optimization processing unit in an automated shell-making line environment simulation system provided in an embodiment of this application. (Combined with...) Figure 2 The specific structure of the optimized processing unit shown in this application is also provided. Figure 3 This diagram illustrates the data flow between components in an automated shell-making line environment simulation system. Here, "components" refers to the various units and modules mentioned in the technical solution of this application.

[0125] exist Figure 2 In the example, the optimization processing unit specifically includes: an air handling module 301, a load calculation module 302, and an airflow analysis module 303. Combined with... Figure 3 The air handling module 301, load calculation module 302, and airflow analysis module 303 are each connected to the heat and mass transfer model establishment unit 20 and can transmit data to the heat and mass transfer model establishment unit 20. In addition, the environmental parameter testing unit 10 can also transmit data to the heat and mass transfer model establishment unit 20.

[0126] In this embodiment of the application, the air treatment module 301 is used to simulate and optimize the interaction between air and the shell during the drying process, and to treat the air before it enters the drying chamber.

[0127] The load calculation module 302 is used to monitor real-time data during the drying process, dynamically adjust the parameters of the air conditioning system, and thus obtain the required cooling load and humidity load.

[0128] The airflow analysis module 303 is used to simulate and optimize the distribution of airflow on and around the shell, and to analyze the impact of airflow on heat transfer and mass transfer during the drying process.

[0129] The following describes the air handling work performed by the air handling module 301.

[0130] In an optional implementation, the air handling module 301 processes the air before it enters the drying chamber, specifically including: return air diversion and pretreatment, air cooling and dehumidification, air mixing and treatment in the mixing box, humidification and heating, and adjustment of air volume and speed.

[0131] The air handling module 301 performs return air diversion and pretreatment, including: at the large return air inlet, the return air entering the air conditioning unit is first divided into two parts: one part of the air enters the surface cooler for cooling and dehumidification; the other part of the air directly enters the mixing box, mixes with the air coming out of the surface cooler and dehumidifier, and is then further processed by the humidifier and heater.

[0132] The air handling module 301 performs air cooling and dehumidification, including: cooling and dehumidifying the return air entering the surface cooler, reducing the air temperature and removing some moisture; the treated air is then sent to the mixing box through the upper part of the air conditioning unit. The air enters the rotary dehumidifier through the dehumidifier's return air vent, where it undergoes isenthalpic dehumidification to reduce humidity. The dehumidified air is then sent to the mixing box to mix with the air exiting the surface cooler.

[0133] The air handling module 301 mixes and processes the air in the mixing box, including: in the mixing box, by mixing with the air from the surface cooler and dehumidifier outlet, the humidity and temperature of the air are further regulated. The mixed air then enters the humidifier and heater for further humidification and heating to achieve the set temperature and humidity requirements.

[0134] The air handling module 301 performs humidification and heating processes, including: the air after mixing is humidified by a humidifier to increase the humidity of the air; and the heater is responsible for raising the temperature of the air to ensure that the air reaches the required dry conditions.

[0135] The air handling module 301 regulates airflow and speed, including adjusting the fan speed based on signals output by a PID controller. These signals originate from the difference between the actual and set values ​​measured by indoor temperature and humidity sensors. The PID controller adjusts the airflow processed by each device by regulating the fan speed. It is important to note that the airflow from the outlet and the dehumidifier remains constant; only the airflow entering the surface cooler and mixing section changes.

[0136] The air handling module 301 delivers air to the drying chamber, including: the air that has been humidified, heated and mixed is finally delivered into the drying chamber to complete the drying process of the shell.

[0137] Next, the specific types of cooling and wet loads obtained by the load calculation module 302 will be described. In the optional implementation, the cooling loads obtained by the load calculation unit include: external wall cooling load, equipment cooling load, outdoor wind intrusion cooling load, shell latent heat cooling load, and shell sensible heat cooling load. Here, "external wall" refers to the external wall of the drying chamber. The wet loads obtained by the load calculation unit include: shell moisture dissipation and outdoor intrusion wet load.

[0138] In the optional implementation method, the formula for calculating the external wall cooling load is:

[0139] ;

[0140] in, This refers to the cooling load of the exterior walls. Calculate the area of ​​the enclosure structure of the dry chamber; The dry-bulb temperature of the air inside the factory building; This refers to the dry bulb temperature inside the drying chamber. The heat transfer coefficient of the building envelope is calculated using the following formula:

[0141] ;

[0142] in, The thickness of each layer of material; This represents the thermal conductivity of each layer of material. Here, "each layer of material" refers to each layer of coating.

[0143] The formula for calculating the equipment cooling load is:

[0144] ;

[0145] in, The cooling load generated by the heat generated by the equipment (i.e., equipment cooling load). The number of fans inside the drying chamber; The fan opening degree inside the drying chamber; The operating power of a single fan; This is the power factor of the fan.

[0146] The formula for calculating the outdoor wind intrusion cooling load is:

[0147] ;

[0148] in, This is due to the intrusion of outdoor wind into the cooling load. This refers to the air intake volume of the automatic door. The enthalpy value of the air outside the drying chamber; This is the enthalpy value inside the drying chamber.

[0149] The formula for calculating the latent heat cooling load of the shell is:

[0150] ;

[0151] in, The latent heat cooling load formed by moisture dissipation from the shell (i.e., the latent heat cooling load of the shell). It is the heat of condensation; This refers to the quality loss rate.

[0152] The formula for calculating the sensible heat cooling load of the shell is:

[0153] ;

[0154] in, The sensible heat and cold load of the shell; The heat capacity of the coating; This is the weight of the paint; This represents the temperature difference between the paint and the indoor temperature.

[0155] Based on the various cooling loads introduced above, the following table presents the total cooling load for each type, as well as the total cooling load of the air conditioning system calculated by combining the total cooling loads of each type.

[0156] Q1 = q1h;

[0157] Q2 = q2h;

[0158] Q3 = 0.2q3h;

[0159] Q4 = q4h;

[0160] Q5 = q5h;

[0161] Q z =Q5+Q1+Q2+Q3-Q4;

[0162] In the above formula, Q z Q1 is the total cooling load of the air conditioning system; Q2 is the total cooling load due to heat transfer from the external walls; Q3 is the total cooling load due to outdoor air intrusion, where 0.2 represents a dynamic correction coefficient; Q4 is the total latent heat cooling load of the casing; and Q5 is the total sensible heat cooling load of the casing. The term 'h' in the formula represents the duration of the load calculation. Q4 is essentially a cooling load offsetting term, representing the effective cooling capacity provided by the environment or equipment to the room. This cooling capacity directly reduces the cooling demand of the air conditioning system and therefore needs to be subtracted from the total cooling load calculation.

[0163] The moisture loss from the mold shell is the amount of water lost during the drying process. It can be calculated from the change in the shell's mass (i.e., the mass difference before and after drying) and the drying time. The moisture loss from the mold shell directly affects air humidity, therefore requiring systematic processing.

[0164] The formula for calculating the moisture dissipation of the shell is:

[0165] ;

[0166] in, This refers to the moisture dissipation of the shell. The number of fully loaded shells inside the dry chamber; This is the weight of the shell before drying; This is the weight of the shell after drying; This refers to the drying time.

[0167] Outdoor intrusion moisture load refers to the increase in humidity inside the drying chamber caused by the moisture brought in by outside air entering the chamber. In practical applications, the moisture load can be calculated based on the airflow through the outside door and the humidity difference between the inside and outside. The formula for calculating outdoor intrusion moisture load is:

[0168] ;

[0169] in, Outdoor intrusion moisture load; The amount of air that enters when the outer door is opened; This refers to the moisture content of the air outside the drying chamber. This refers to the humidity content of the air inside the drying chamber.

[0170] In the technical solution of this application, the load calculation module 302 can dynamically adjust the required cooling load and humidity load by monitoring real-time data (such as temperature and humidity, shell weight, etc.) during the drying process. For example, at different stages of drying, as the moisture in the shell evaporates, the latent heat cooling load and sensible heat cooling load of the shell will change, and the load calculation module 302 can automatically adjust the cooling and humidity control strategies of the air conditioning system according to these changes.

[0171] By accurately calculating cooling loads (such as exterior wall cooling load, equipment cooling load, and outdoor air intrusion cooling load), the energy consumption of air conditioning systems can be optimized. Dynamic adjustment of the cooling load avoids over-cooling or over-heating, thus effectively saving energy. Furthermore, the required cooling load can be dynamically allocated based on the actual drying process. For example, calculating the latent heat and sensible heat cooling load of the air conditioning unit helps adjust the cooling capacity at different stages, thereby improving energy efficiency. Through moisture load calculations (air conditioning unit moisture dissipation and outdoor moisture load), air humidity can be effectively controlled, preventing excessively high or low humidity from affecting the drying process and improving drying quality and efficiency to a certain extent.

[0172] Furthermore, by accurately calculating and simulating the heat transfer and mass transfer models for shell drying, it is possible to better predict temperature and humidity changes at each stage of the shell drying process, ensuring that temperature and humidity conditions remain within the optimal range throughout the drying process. This can significantly improve the drying effect and reduce uneven drying.

[0173] The airflow analysis module 303 is used to simulate and optimize the distribution of airflow on and around the shell surface, and to analyze the impact of airflow on heat transfer and mass transfer during the drying process.

[0174] The automated shell-making line environmental simulation system provided in this application includes an environmental parameter testing unit, a heat and mass transfer model establishment unit, and an optimization processing unit. The environmental parameter testing unit tests and evaluates environmental parameters, including wind speed, and feeds this data back to the heat and mass transfer model establishment unit. This helps the heat and mass transfer model establishment unit to build a dual model that fully considers wind speed variations: a shell drying heat transfer model and a shell drying mass transfer model. The shell drying heat transfer model characterizes the heat transferred through the shell during the drying process, while the shell drying mass transfer model describes the process of moisture evaporating from the coating through the surface into the air. Both models are related to environmental parameters such as wind speed and take into account wind speed variations. Therefore, in environments with unstable or highly variable wind speeds, the simulation effect is more realistic than existing drying simulation schemes, avoiding significant deviations and thus contributing to achieving more ideal drying results in actual operation. Furthermore, in the automated shell-making line environmental simulation system, the optimization processing unit further incorporates the effects of load, airflow within the drying chamber, and air into the established shell drying heat transfer and mass transfer models to simulate and optimize these two models. This makes the simulation more realistic and accurate, enabling more precise prediction of heat and mass changes during the drying process, and thus helping to guide the control of the shell drying process under suitable temperature, humidity, and wind speed.

[0175] It should be noted that the various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. The units, modules, etc., described as separate components in the system may or may not be physically separate. Some or all of the units or modules can be selected to achieve the purpose of the solution in this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0176] The above description is merely one specific 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.

Claims

1. An automated shell-making line environment simulation system, characterized in that, The system includes: an environmental parameter testing unit, a heat and mass transfer model establishment unit, and an optimization processing unit; the environmental parameter testing unit and the optimization processing unit are both connected to the heat and mass transfer model establishment unit. The environmental parameter testing unit is used to test the environmental parameters affecting the drying process of the shell-making drying chamber using testing equipment, and to evaluate the uniformity of airflow in the drying chamber and the changes in the environmental parameters. The test and evaluation results are then sent to the heat and mass transfer model establishment unit. The environmental parameters include at least wind speed. The heat and mass transfer model establishment unit is used to establish a shell drying heat transfer model and a shell drying mass transfer model. After the model is established, the shell drying heat transfer model and the shell drying mass transfer model are evaluated based on the model performance index, and the influence of environmental parameters on shell heat transfer and mass transfer is analyzed based on the information transmitted by the environmental parameter testing unit. The optimization processing unit is used to simulate and optimize the effects of load, airflow in the drying chamber, and air in the established shell drying heat transfer model and shell drying mass transfer model.

2. The system according to claim 1, characterized in that, The heat and mass transfer model establishment unit is also used to optimize the established model by introducing the influence factors of environmental heat transfer and the non-uniformity of the coating layer during the process of establishing the shell drying heat transfer model and the shell drying mass transfer model.

3. The system according to claim 1, characterized in that, The optimization processing unit specifically includes: an air handling module, a load calculation module, and an airflow analysis module; The air treatment module is used to simulate and optimize the interaction between air and the shell during the drying process, and to treat the air before it enters the drying chamber. The load calculation module is used to monitor real-time data during the drying process, dynamically adjust the parameters of the air conditioning system, and thus obtain the required cooling load and humidity load. The airflow analysis module is used to simulate and optimize the distribution of airflow on and around the surface of the shell, and to analyze the impact of airflow on heat transfer and mass transfer during the drying process.

4. The system according to claim 3, characterized in that, The air handling module processes the air before it enters the drying chamber, including: return air diversion and pretreatment, air cooling and dehumidification, air mixing and treatment in the mixing box, humidification and heating, and adjustment of air volume and speed.

5. The system according to claim 3, characterized in that, The cooling load obtained by the load calculation unit includes: external wall cooling load, equipment cooling load, outdoor wind intrusion cooling load, shell latent heat cooling load, and shell sensible heat cooling load; The wet load obtained by the load calculation unit includes: shell moisture dissipation and outdoor intrusion wet load.

6. The system according to claim 5, characterized in that, The formula for calculating the external wall cooling load is as follows: ； in, The external wall cooling load; Calculate the area of ​​the building envelope; The dry-bulb temperature of the air inside the factory building; This refers to the dry bulb temperature inside the drying chamber. The heat transfer coefficient of the building envelope is calculated using the following formula: ； in, The thickness of each layer of material; The thermal conductivity of each layer of material; The formula for calculating the cooling load of the equipment is as follows: ； in, The cooling load generated by the heat generated by the equipment; The number of fans inside the drying chamber; The fan opening degree inside the drying chamber; The operating power of a single fan; This is the power factor of the fan; The formula for calculating the outdoor wind intrusion cooling load is as follows: ； in, This is due to the intrusion of outdoor wind into the cooling load. This refers to the air intake volume of the automatic door. The enthalpy value of the air outside the drying chamber; This refers to the enthalpy value inside the drying chamber; The formula for calculating the latent heat cooling load of the shell is as follows: ； in, The latent heat cooling load is generated by moisture dissipation from the shell. It is the heat of condensation; This refers to the quality loss rate; The formula for calculating the sensible heat load of the shell is as follows: ； in, The sensible heat and cold load of the shell; The heat capacity of the coating; This is the weight of the paint; This is the temperature difference between the paint and the indoor temperature. The formula for calculating the moisture dissipation of the shell is as follows: ； in, This refers to the amount of moisture dissipated from the shell. The number of fully loaded shells inside the dry chamber; This is the weight of the shell before drying; This is the weight of the shell after drying; Drying time; The formula for calculating the outdoor intrusive moisture load is as follows: ； in, Outdoor intrusion moisture load; The amount of air that enters when the outer door is opened; This refers to the moisture content of the air outside the drying chamber. This refers to the humidity content of the air inside the drying chamber.

7. The system according to claim 1, characterized in that, The expression for the shell drying heat transfer model is as follows: ； in, Heat transfer per unit time; The latent heat of vaporization of water is taken as 2448.6 kJ / kg; The heat capacity of the coating; This is the weight of the paint; This is the temperature difference between the paint and the indoor temperature. For the mass loss rate, the calculation relationship is shown in the expression of the shell drying mass transfer model described below: ； in, For moisture content; The mass transfer factor is related to wind speed; To maintain the coating temperature The saturated vapor pressure below; The ambient vapor pressure; This refers to the amount of sand applied. The density of the coating; The thickness of the coating; the expression for the amount of sand applied (m) is: ； in, Let be the surface area of ​​the shell.

8. The system according to claim 2, characterized in that, The heat and mass transfer model building unit optimizes the established model by incorporating the influence of environmental heat transfer and the non-uniformity of the coating layer. The expression for the optimized shell drying heat transfer model is as follows: ； Among them, among them, Heat transfer per unit time; The latent heat of vaporization of water is taken as 2448.6 kJ / kg; The heat capacity of the coating; This is the weight of the paint; This is the temperature difference between the paint and the indoor temperature. For quality loss rate: Additional heat transfer caused by environmental factors; The optimized formula for the shell drying mass transfer model is expressed as follows: ； in, For moisture content; The mass transfer factor is related to wind speed; To maintain the coating temperature The saturated vapor pressure below; The ambient vapor pressure; This refers to the amount of sand applied. The density of the coating; The thickness of the coating; This is a correction factor; The surface area of ​​the shell; This refers to wind speed.

9. The system according to claim 1, characterized in that, The environmental parameter testing unit is specifically used to evaluate the uniformity of airflow within the drying chamber and the variation of the environmental parameters through standard deviation and coefficient of variation; wherein, the formula for calculating the standard deviation is: ； in, The standard deviation; For the first The measured wind speed at each sampling data point; The average wind speed across all sampled data points; This represents the total number of wind speed sampling data points; ; ； in, is the coefficient of variation.

10. The system according to claim 1, characterized in that, The model performance indices include one or more of the following: coefficient of determination, mean square error, and root mean square error.

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