Analog simulation calculation method, device, equipment and medium for temperature field of rotary cement kiln

Abstract

The invention provides a rotary cement kiln temperature field analog simulation calculation method, device and equipment and a medium. The rotary cement kiln temperature field analog simulation calculation is divided into a solid calculation domain and a fluid calculation domain based on equipment structure information and a production process of a rotary cement kiln; constructing a solid heat conduction control equation for the solid computational domain, and constructing a basic control equation for the fluid computational domain; solving the solid heat conduction control equation to obtain a solid computational domain temperature field simulation calculation result; the basic control equation is subjected to flow field simulation calculation, a fluid computational domain simulation calculation result is output, a dynamic temperature field in the rotary cement kiln is displayed through analogue simulation, a reliable basis is provided for real-time monitoring of conditions such as abrasion of refractory materials in the rotary cement kiln, and therefore equipment safety and stable production operation of the rotary cement kiln are guaranteed; only an energy conservation equation needs to be calculated for a solid material area, a velocity field and a pressure field do not need to be calculated, and the problems that the calculation amount is large and convergence cannot be achieved during simulation are effectively solved.

Description

Technical Field

[0001] The invention relates to the technical field of simulation calculation of the internal temperature field of a cement rotary kiln, and in particular to a method, device, equipment and storage medium for simulating and calculating the temperature field of a cement rotary kiln. Background Art

[0002] The rotary kiln is a key equipment for cement production. The working conditions inside the kiln change frequently, and complex physical and chemical reactions will occur during the clinker burning process. The monitoring of the temperature field of the rotary kiln is extremely important for production and safety. Since the rotary kiln is long and is still rotating, it is difficult to monitor its internal temperature field. The traditional monitoring of the internal temperature field of the rotary kiln is mainly divided into two parts: the fire-watching TV system at the kiln head and the cylinder infrared thermal imaging system. Because the cement process is to grind the raw materials and coal into powder and send them into the kiln by wind after drying, the solid particles in the kiln fly throughout the kiln space, resulting in large "dust", which affects the output effect of the fire-watching TV system at the kiln head. The cylinder infrared thermal imaging system only involves the measurement of the temperature field and some basic image enhancement functions, and cannot realize the dynamic prediction of the internal temperature field of the rotary kiln and the monitoring of refractory loss and crusting. Summary of the invention

[0003] The present invention provides a cement rotary kiln temperature field simulation calculation method, device, equipment and storage medium, which are used to solve the defects of the traditional cement rotary kiln temperature field simulation calculation method, that is, the simulation calculation results are inaccurate, and the monitoring of the internal temperature field of the rotary kiln and the monitoring of the refractory material loss and crusting cannot be realized.

[0004] The present invention provides a cement rotary kiln temperature field simulation calculation method, comprising: Based on the equipment structure information and production process of cement rotary kiln, the simulation calculation of rotary kiln temperature field is divided into solid calculation domain and fluid calculation domain; Constructing a solid heat conduction control equation for the solid computational domain, and constructing a basic control equation for the fluid computational domain; Solve the solid heat conduction control equation according to the law of conservation of energy to obtain the simulation calculation result of the temperature field in the solid calculation domain; Use fluid mechanics simulation software to perform flow field simulation calculations on the basic control equations, and output simulation calculation results for the fluid calculation domain.

[0005] According to the cement rotary kiln temperature field simulation calculation method provided by the present invention, the rotary kiln further includes a coupling calculation domain; In the coupling calculation domain, the raw material is regarded as a fluid, and the flow field simulation calculation of the basic control equation is performed using the partition fluid model of fluid mechanics simulation software, and the simulation calculation results of the coupling calculation domain are output.

[0006] According to the cement rotary kiln temperature field simulation calculation method provided by the present invention, the basic control equation includes a turbulence model, a pulverized coal combustion model, a radiation model and an energy equation source term; The turbulence model, the pulverized coal combustion model, the radiation model and the energy equation source term are coupled and solved, and the simulation calculation results of the fluid calculation domain and / or the simulation calculation results of the coupling calculation domain are output.

[0007] According to the cement rotary kiln temperature field simulation calculation method provided by the present invention, the fluid calculation domain simulation calculation results include static simulation calculation results and dynamic prediction results, and the dynamic prediction result calculation method includes: Calculate the initial flow field under steady-state flow process; The combustion process in the kiln is simulated. After the combustion process is stable, the fluid is frozen and the simulation calculation results of the fluid calculation domain are output. The simulation calculation results of the fluid calculation domain include one or more of the temperature, velocity, and concentration of each gas component of the gas and material inside the rotary kiln.

[0008] According to the cement rotary kiln temperature field simulation calculation method provided by the present invention, the simulation of the combustion process in the kiln includes: Boundary conditions are set according to the heat exchange amount in the cement rotary kiln, and the heat exchange amount includes at least one of heat transfer between the flue gas in the kiln and the kiln material through convection and radiation, heat transfer between the flue gas in the kiln and the kiln wall through convection and radiation, heat transfer through heat conduction of the kiln wall covered by the kiln material, heat exchange between the top surface of the kiln material and the uncovered kiln wall through thermal radiation, and heat exchange between the outer wall of the kiln wall and the environment through convection and radiation; The boundary conditions include: the speed and temperature of the primary and secondary air and the kiln head hood pressure are used as the inlet boundary conditions at the kiln head, the flue gas temperature and the smoke chamber pressure are used as the outlet boundary conditions at the kiln tail, the convection radiation mixed boundary conditions are set on the outer wall of the kiln wall, and the kiln wall convection heat transfer coefficient and radiation emission coefficient are estimated by empirical formulas. The coal powder boundary conditions are set through the incident port of the DPM model, and the coal powder boundary conditions include the incident velocity, temperature, mass flow rate, industrial analysis results and particle size distribution of the coal powder; The combustion process in the kiln is simulated based on the boundary conditions.

[0009] According to the cement rotary kiln temperature field simulation calculation method provided by the present invention, the simulation of the combustion process in the kiln includes: Estimate the length of the decomposition zone, transition zone, sintering zone and cooling zone in the cement rotary kiln, as well as the scope of the raw material area; According to the chemical reactions, components and heat absorption and release of the decomposition zone, transition zone, sintering zone and cooling zone, boundary parameters are estimated, wherein the boundary parameters include heat absorption and release power, thermal conductivity and specific heat of the chemical reactions in each zone; The combustion process in the kiln is simulated based on the boundary parameters.

[0010] The cement rotary kiln temperature field simulation calculation method provided by the present invention also includes: According to the temperature field simulation calculation results of the solid calculation domain and the temperature field simulation calculation results of the fluid calculation domain, the external temperature field simulation calculation results of the rotary kiln are calculated in combination with the refractory heat transfer calculation results of different calculation domains.

[0011] The present invention also provides a cement rotary kiln temperature field simulation calculation device, comprising: A partitioning module is used to divide the rotary kiln temperature field simulation calculation into a solid calculation domain and a fluid calculation domain based on the equipment structure information and production process of the cement rotary kiln; A construction module, used for constructing a solid heat conduction control equation for the solid calculation domain and a basic control equation for the fluid calculation domain; The first calculation module is used to solve the solid heat conduction control equation according to the law of conservation of energy to obtain the simulation calculation result of the temperature field in the solid calculation domain; The second calculation module is used to use fluid mechanics simulation software to perform flow field simulation calculation on the basic control equation and output the simulation calculation results of the fluid calculation domain.

[0012] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method for simulating and calculating the temperature field of a cement rotary kiln as described in any one of the above items is implemented.

[0013] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the method for simulating and calculating the temperature field of a cement rotary kiln described in any one of the above items is implemented.

[0014] The present invention provides a cement rotary kiln temperature field simulation calculation method, device, equipment and storage medium. Based on the equipment structure information and production process of the cement rotary kiln, the rotary kiln temperature field simulation calculation is divided into a solid calculation domain and a fluid calculation domain; a solid heat conduction control equation is constructed for the solid calculation domain, and a basic control equation is constructed for the fluid calculation domain; the solid heat conduction control equation is solved according to the law of conservation of energy to obtain a temperature field simulation calculation result of the solid calculation domain; a fluid mechanics simulation software is used to perform flow field simulation calculation on the basic control equation, and the simulation calculation result of the fluid calculation domain is output. The dynamic temperature field inside the rotary kiln is displayed through simulation, so as to provide a reliable basis for the real-time monitoring of refractory material wear and other conditions in the kiln, thereby ensuring the safety of the rotary kiln equipment and the stable operation of production. In addition, by adopting the method of dividing the calculation domain, only the energy conservation equation needs to be calculated for the solid material area, and there is no need to calculate useless velocity field and pressure field, which effectively solves the problem of large amount of calculation and failure to converge during simulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 It is a schematic diagram of a flow chart of a cement rotary kiln temperature field simulation calculation method provided by an embodiment of the present invention; Figure 2 It is a logical relationship framework diagram of the rotary kiln calculation domain provided by an embodiment of the present invention; Figure 3 is a diagram of the calculation result of the temperature field inside the rotary kiln provided by an embodiment of the present invention; Figure 4 is a diagram showing the calculation result of the gas concentration inside the rotary kiln provided by an embodiment of the present invention; Figure 5 is a diagram showing the calculation results of the external temperature field of a rotary kiln provided by an embodiment of the present invention; Figure 6 It is a functional structure diagram of a cement rotary kiln temperature field simulation and emulation calculation device provided by an embodiment of the present invention; Figure 7 It is a functional structure diagram of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] Figure 1 The flowchart of the cement rotary kiln temperature field simulation calculation method provided by the embodiment of the present invention is as follows: Figure 1 As shown, the cement rotary kiln temperature field simulation calculation method provided by the embodiment of the present invention includes: Step 101: dividing the rotary kiln temperature field simulation calculation into a solid calculation domain and a fluid calculation domain based on the equipment structure information and production process of the cement rotary kiln; The simulation of the temperature field in the cement rotary kiln involves calculation models such as flow, heat transfer, radiation, and combustion. The simulation model mainly includes three calculation domains: kiln wall, kiln material, and flue gas. The kiln wall is a solid calculation domain, which can be divided into different sub-calculation domains according to different physical properties. The kiln material and flue gas are fluid domains. Coal powder enters the calculation domain of flue gas as a discrete phase, and the combustion reaction of coal powder is considered.

[0019] In the embodiment of the present invention, the input data required for simulation is first determined according to the specific scenario of the cement rotary kiln, and the data collection, sorting and conversion are completed. The input data mainly includes but is not limited to the following parameters: Cement rotary kiln equipment structural model, inclination angle and rotation speed, mainly internal dimensions; inlet and outlet parameters: including primary and secondary air volume, inlet air temperature and inlet and outlet pressure, and the tangential wind speed of the corresponding swirl wind at the burner; kiln feed amount and coal feed amount; kiln material properties, including density, specific heat capacity, thermal conductivity, particle size distribution, etc.; coal powder properties, including calorific value, particle size distribution, density, thermal conductivity, volatile matter ratio, etc.; kiln wall properties, including density, specific heat capacity, thermal conductivity, etc.

[0020] Based on the input data, the calculation domain of the cement rotary kiln is determined, reasonable simplification is performed, the corresponding geometric model is established, and the geometric model is meshed. It should be noted that the mesh size can be determined according to the required calculation accuracy.

[0021] Step 102: constructing a solid heat conduction control equation for the solid calculation domain, and constructing a basic control equation for the fluid calculation domain; Step 103, solving the solid heat conduction control equation according to the law of conservation of energy to obtain a simulation calculation result of the temperature field in the solid calculation domain; Step 104: Use fluid mechanics simulation software to perform flow field simulation calculations on the basic control equations, and output simulation calculation results of the fluid calculation domain.

[0022] The traditional method of calculating the temperature field of the cement rotary kiln through the fire-viewing TV system at the kiln head and the infrared thermal imaging system of the cylinder is that the cement process is to grind the raw materials and coal into powder, dry them, and then send them into the kiln by wind. The solid particles in the kiln fly throughout the space inside the kiln, causing a large amount of "dust", which affects the output effect of the fire-viewing TV system at the kiln head. The infrared thermal imaging system of the cylinder only involves the measurement of the temperature field and some basic image enhancement functions, and cannot realize the dynamic prediction of the temperature field inside the rotary kiln and the monitoring of refractory loss and crusting.

[0023] The cement rotary kiln temperature field simulation calculation method provided in the embodiment of the present invention divides the rotary kiln temperature field simulation calculation into a solid calculation domain and a fluid calculation domain based on the equipment structure information and production process of the cement rotary kiln; constructs a solid heat conduction control equation for the solid calculation domain, and constructs a basic control equation for the fluid calculation domain; solves the solid heat conduction control equation according to the law of conservation of energy to obtain the temperature field simulation calculation result of the solid calculation domain; uses fluid mechanics simulation software to perform flow field simulation calculation on the basic control equation, outputs the simulation calculation result of the fluid calculation domain, and presents the dynamic temperature field inside the rotary kiln through simulation, thereby providing a reliable basis for real-time monitoring of refractory material wear and other conditions in the kiln, thereby ensuring the safety of the rotary kiln equipment and stable production operation. In addition, by adopting the method of dividing the calculation domain, only the energy conservation equation needs to be calculated for the solid material area, and there is no need to calculate useless velocity field and pressure field, which effectively solves the problem of large amount of calculation and failure to converge during simulation.

[0024] Based on any of the above embodiments, the embodiment of the present invention provides a cement rotary kiln temperature field simulation calculation method, wherein the rotary kiln further includes a coupling calculation domain; In the coupling calculation domain, the raw material is regarded as a fluid, and the flow field simulation calculation of the basic control equation is performed using the partition fluid model of fluid mechanics simulation software, and the simulation calculation results of the coupling calculation domain are output.

[0025] Based on any of the above embodiments, the basic control equations include a turbulence model, a pulverized coal combustion model, a radiation model and an energy equation source term; The turbulence model, the pulverized coal combustion model, the radiation model and the energy equation source term are coupled and solved, and the simulation calculation results of the fluid calculation domain and / or the simulation calculation results of the coupling calculation domain are output.

[0026] like Figure 2As shown, the temperature field and velocity field of the flow area in the kiln are obtained by solving the basic control equations of multi-component flow. In this process, it is necessary to couple and solve the turbulence model, pulverized coal combustion model, and radiation model to consider the influence of turbulent flow, pulverized coal combustion, and radiation on the flow field and temperature field of the fluid domain; the temperature field of the solid area is calculated by solving the heat conduction control equation of the solid area; the fluid area and the solid area are coupled through the interface to solve the heat transfer and radiation through the fluid-solid interface.

[0027] The flue gas flow in the cement rotary kiln is obtained by solving the steady-state NS equations and turbulence equations; the temperature field is obtained by solving the energy equation; the radiation heat transfer uses the DO radiation model, considering the radiation heat transfer between the kiln wall, kiln material and flue gas, and is coupled with the temperature field through the energy equation source term; the pulverized coal movement is simulated by the DPM model, and the heat release of combustion is obtained through the pulverized coal combustion model, which is coupled with the temperature field through the energy equation source term; the kiln charge reaction is judged according to the kiln charge temperature and position, and is divided into decomposition zone, transition zone, firing zone and cooling zone, and the endothermic heat (or exothermic heat) is calculated according to the reaction type, and is coupled with the temperature field through the energy equation source term.

[0028] In an embodiment of the present invention, the fluid computing domain simulation calculation results include static simulation calculation results and dynamic prediction results, and the dynamic prediction result calculation method includes: Calculate the initial flow field under steady-state flow process; The combustion process in the kiln is simulated. After the combustion process is stable, the fluid is frozen and the simulation calculation results of the fluid calculation domain are output. The simulation calculation results of the fluid calculation domain include one or more of the temperature, velocity, and concentration of each gas component of the gas and material inside the rotary kiln.

[0029] The model is debugged for different working conditions to obtain converged and stable results. According to the degree of influence on the calculation results, the model is simplified as much as possible to reduce the calculation scale. The specific calculation process is as follows: First, CFD software is used to simulate the flow field of cement rotary kiln and burner model. The flow field calculation adopts steady-state calculation, the turbulence model adopts k-ε model, and the numerical algorithm adopts SIMPLE algorithm; then the combustion process in the kiln is numerically simulated. First, the steady-state flow process is calculated (heat transfer / combustion is not considered), and then the result of the steady-state flow process is used as the initial flow field to calculate the combustion process in the kiln. The heat absorption and release power density is applied to the raw material as the energy source term. The turbulence model adopts RNG k-ε model, the numerical algorithm adopts PISO algorithm, the combustion model plans to adopt non-premixed combustion model, the coal powder incident is tracked by Lagrangian method, the radiation model adopts P1 or DO radiation model, and solid heat transfer is considered in the simulation process. Finally, since the time scale of the heat transfer process is much larger than the time scale of flow combustion, after the combustion process is basically stable, the fluid is frozen and only the energy equation is calculated until the calculation is stable or the required time is reached.

[0030] It should be noted that the above models are common models in this field and will not be described in detail here.

[0031] The flow in the rotary kiln is a typical gas-solid two-phase coupled turbulent flow with chemical reactions. This scheme adopts the method of "partition solution, boundary coupling" to perform numerical calculations on the fluid-solid coupling problem in the rotary kiln. This calculation method treats the high-temperature gas flow domain and the material flow domain as different regions relatively independently, establishes control equations for different calculation regions, and calculates them separately. The regions influence each other through the coupling relationship at the interface (such as temperature continuity, heat flux continuity, etc.). For the solid material region, only the energy conservation equation needs to be calculated, and there is no need to calculate useless velocity fields and pressure fields, which effectively solves the problem of large amount of calculation and failure to converge during simulation. It is beneficial to save storage space and calculation amount.

[0032] In an embodiment of the present invention, the simulated kiln combustion process includes: Boundary conditions are set according to the heat exchange amount in the rotary kiln, and the heat exchange amount includes at least one of heat transfer between the flue gas in the kiln and the kiln material through convection and radiation, heat transfer between the flue gas in the kiln and the kiln wall through convection and radiation, heat transfer through heat conduction of the kiln wall covered by the kiln material, heat exchange between the top surface of the kiln material and the uncovered kiln wall through thermal radiation, and heat exchange between the outer wall of the kiln wall and the environment through convection and radiation; The boundary conditions include: the speed and temperature of the primary and secondary air and the kiln head hood pressure are used as the inlet boundary conditions at the kiln head, the flue gas temperature and the smoke chamber pressure are used as the outlet boundary conditions at the kiln tail, the convection radiation mixed boundary conditions are set on the outer wall of the kiln wall, and the kiln wall convection heat transfer coefficient and radiation emission coefficient are estimated by empirical formulas. The coal powder boundary conditions are set through the incident port of the DPM model, and the coal powder boundary conditions include the incident velocity, temperature, mass flow rate, industrial analysis results and particle size distribution of the coal powder; The combustion process in the kiln is simulated based on the boundary conditions.

[0033] In an embodiment of the present invention, the simulated kiln combustion process includes: Estimate the length of the decomposition zone, transition zone, sintering zone and cooling zone in the cement rotary kiln, as well as the scope of the raw material area; According to the chemical reactions, components and heat absorption and release of the decomposition zone, transition zone, sintering zone and cooling zone, boundary parameters are estimated, wherein the boundary parameters include heat absorption and release power, thermal conductivity and specific heat of the chemical reactions in each zone; The combustion process in the kiln is simulated based on the boundary parameters.

[0034] In the embodiment of the present invention, the raw material absorbs and releases heat in the rotary kiln, and the simulation takes into account the absorption of radiant heat. The process of clinker formation in the cement rotary kiln, the kiln material preheated and calcined by the preheater and calciner still contains a certain amount of CaCO3, which will be calcined in the kiln to form CaO. When the kiln material passes through the high temperature zone in the rotary kiln, a series of chemical and mineralogical reactions occur. The components of the kiln material (such as calcium oxide, aluminum oxide, iron oxide, silicon dioxide and other metal oxides) interact with each other and eventually form four main components of cement clinker: 3CaO·SiO2 (C3S), 2CaO·SiO2 (C2S), 3CaO·Al2O3 (C3A) and 4CaO·Al2O3·Fe2O3 (C4AF). The formation temperatures of these clinker components are different. Therefore, according to the temperature requirements of different components, modern dry process cement rotary kilns can be divided into four zones (decomposition zone, transition zone (temperature increase and exothermic reaction zone), sintering zone and cooling zone).

[0035] Decomposition zone: The decomposition rate of the raw materials from the preheater outlet is about 85%-95%. After entering the rotary kiln, the raw materials are heated by the high-temperature gas and the kiln wall, and the decomposition reaction continues. In this area, a small amount of CaO·Al2O3 (CA), CaO·Fe2O3 (CF), 2CaO·Fe2O3 (C2F) and 5CaO·3Al2O3 (C5A3) are formed. The main reactions are as follows: CaCO3— CaO + CO2 (650-900°C)

[0036] CaO +Al2O3— CaO·Al2O3(800°C)

[0037] CaO + Fe2O3— CaO·Fe2O3(800°C)

[0038] CaO + CaO·Fe2O3— 2CaO·Fe2O3(800°C)

[0039] 3(CaO·Al2O3) + 2CaO — 5CaO·3Al2O3(900-950°C)

[0040] The proportion of undecomposed CaCO3 in the kiln charge is 15%, and the feed temperature is 850°C. At the exit of the decomposition zone, we believe that the CaCO3 is fully converted and the temperature of the kiln charge has risen to 900°C.

[0041] 2CaO + SiO2— 2CaO·SiO2(1000°C)

[0042] 3(2CaO·Fe2O3) + 5CaO3·3Al2O3+ CaO — 3(4CaO·Al2O3·Fe2O3) (1200-1300°C)

[0043] 5CaO·3Al2O3+ 4CaO — 3(3CaO·Al2O3) (1200-1300°C)

[0044] Sintering zone: In this zone, the formation of liquid phase is assumed to occur at 1300 o C or above. At the same time, the main component C3S is formed by the reaction of C2S and free CaO, see the following reaction equation. Finally, the clinker leaves the high temperature area and cools to 1300 o C.

[0045] 2CaO·SiO2+ CaO — 3CaO·SiO2(1350-1450 o C)

[0046] Cooling zone: In a cement rotary kiln, the cooling of clinker is mainly completed in the cooler. Therefore, the cooling zone in the kiln is very short. The embodiment of the present invention ignores the cooling function of this area and assumes that the heat flow in the cooling zone is zero.

[0047] The raw materials will undergo the above very complex endothermic and exothermic reactions in the rotary kiln, and the precise reaction mechanism is difficult to obtain. In this scheme, the influence of the endothermic and exothermic reactions of the raw materials in the rotary kiln is considered in the following way.

[0048] Based on experience, the lengths of the decomposition zone, transition zone, sintering zone and cooling zone in the rotary kiln, as well as the range (height) of the raw material area, are estimated.

[0049] According to the above process flow description, the main chemical reactions in the decomposition zone, transition zone, sintering zone and cooling zone are different, the components are different, and the heat absorption and release of each section are different. The heat absorption and release power of each section chemical reaction is obtained according to the process mechanism. For example, the decomposition section is mainly the endothermic decomposition reaction of calcium carbonate (1656kJ / kg). Assuming that the inlet raw material flow rate is mq (kg / s), the inlet raw material contains 15% calcium carbonate, and the volume of the inlet section raw material is V, the average heat absorption power density of the inlet section is 1656*15%*mq / V. It is processed linearly, that is, the heat absorption power at the inlet of the decomposition section is the largest, and the heat absorption power at the end of the decomposition section is 0. The heat absorption and release of the transition section, sintering section, and cooling section are processed in a similar way.

[0050] The thermal conductivity and specific heat of each segment are estimated based on the main components of each segment.

[0051] The simulation results of the embodiment of the present invention are as follows Figure 3 and Figure 4 As shown, the results can display the three-dimensional dynamic temperature field inside the rotary kiln, including gas and material temperature, velocity, concentration of each gas component and other data; at the same time, the flame shape and combustion conditions can be analyzed through image data.

[0052] The embodiment of the present invention is based on the heat transfer model and the cement rotary kiln process, and displays the dynamic temperature field inside the rotary kiln through simulation, providing a reliable basis for real-time monitoring of refractory wear and other conditions in the kiln, thereby ensuring the safety of rotary kiln equipment and stable production operation.

[0053] In some embodiments of the present invention, it also includes: According to the temperature field simulation calculation results of the solid calculation domain and the temperature field simulation calculation results of the fluid calculation domain, the external temperature field simulation calculation results of the rotary kiln are calculated in combination with the refractory heat transfer calculation results of different calculation domains.

[0054] The simulation results of the external temperature field of the rotary kiln are as follows: Figure 5 As shown in the figure, it is consistent with the measurement data distribution of the actual barrel scanning infrared monitoring system, which can verify the effectiveness and accuracy of this scheme.

[0055] The cement rotary kiln temperature field simulation calculation method provided by the embodiment of the present invention is based on the cement rotary kiln internal dynamic temperature field simulation method combined with process mechanism and CFD, combined with gas-solid flow, heat and mass transfer and coal powder combustion models, to establish a mathematical model of a full-size cement rotary kiln. By performing fluid mechanics calculation and numerical simulation on the rotary kiln with a burner, the velocity and temperature distribution of the gas and material inside the cement rotary kiln are obtained, and the internal "black box" is made transparent by combining process parameter feedback monitoring and barrel scanning infrared data, assisting on-site operators to understand the firing conditions more directly, adjust the control strategy in time, and help enterprises to produce safely.

[0056] The cement rotary kiln temperature field simulation calculation device provided by the present invention is described below. The cement rotary kiln temperature field simulation calculation device described below and the cement rotary kiln temperature field simulation calculation method described above can be referenced to each other.

[0057] Figure 6 The structural diagram of the cement rotary kiln temperature field simulation calculation device provided by the embodiment of the present invention is as follows Figure 6 As shown, the cement rotary kiln temperature field simulation calculation device provided by the embodiment of the present invention includes: A division module 601 is used to divide the rotary kiln temperature field simulation calculation into a solid calculation domain and a fluid calculation domain based on the equipment structure information and production process of the cement rotary kiln; A construction module 602 is used to construct a solid heat conduction control equation for the solid calculation domain and a basic control equation for the fluid calculation domain; The first calculation module 603 is used to solve the solid heat conduction control equation according to the law of conservation of energy to obtain the simulation calculation result of the temperature field in the solid calculation domain; The second calculation module 604 is used to use fluid mechanics simulation software to perform flow field simulation calculation on the basic control equation and output simulation calculation results of the fluid calculation domain.

[0058] The cement rotary kiln temperature field simulation calculation device provided in the embodiment of the present invention divides the rotary kiln temperature field simulation calculation into a solid calculation domain and a fluid calculation domain based on the equipment structure information and production process of the cement rotary kiln; constructs a solid heat conduction control equation for the solid calculation domain, and constructs a basic control equation for the fluid calculation domain; solves the solid heat conduction control equation according to the law of conservation of energy to obtain the temperature field simulation calculation result of the solid calculation domain; uses fluid mechanics simulation software to perform flow field simulation calculation on the basic control equation, outputs the simulation calculation result of the fluid calculation domain, and presents the dynamic temperature field inside the rotary kiln through simulation, thereby providing a reliable basis for realizing real-time monitoring of refractory material wear and other conditions in the kiln, thereby ensuring the safety of rotary kiln equipment and stable production operation. In addition, by adopting the method of dividing the calculation domain, only the energy conservation equation needs to be calculated for the solid material area, and there is no need to calculate useless velocity field and pressure field, which effectively solves the problem of large amount of calculation and failure to converge during simulation.

[0059] Figure 7 An example of a physical structure diagram of an electronic device is shown in FIG. Figure 7As shown, the server may include: a processor 710, a communication interface 720, a memory 730 and a communication bus 740, wherein the processor 710, the communication interface 720 and the memory 730 communicate with each other through the communication bus 740. The memory 730 includes a computer program, an operating system and acquired data, and the processor 710 may call the logic instructions in the memory 730 to execute a simulation calculation method for a temperature field of a cement rotary kiln, the method comprising: dividing the simulation calculation of the temperature field of the rotary kiln into a solid calculation domain and a fluid calculation domain based on the equipment structure information and production process of the cement rotary kiln; constructing a solid heat conduction control equation for the solid calculation domain and a basic control equation for the fluid calculation domain; solving the solid heat conduction control equation according to the law of conservation of energy to obtain a simulation calculation result of the temperature field in the solid calculation domain; using fluid mechanics simulation software to perform flow field simulation calculation on the basic control equation, outputting the simulation calculation result of the fluid calculation domain, and displaying the dynamic temperature field inside the rotary kiln through simulation.

[0060] In addition, the logic instructions in the above-mentioned memory 730 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the relevant technology or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0061] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, it is implemented to execute the cement rotary kiln temperature field simulation calculation method provided by the above-mentioned methods. The method includes: dividing the rotary kiln temperature field simulation calculation into a solid calculation domain and a fluid calculation domain based on the equipment structure information and production process of the cement rotary kiln; constructing a solid heat conduction control equation for the solid calculation domain, and constructing a basic control equation for the fluid calculation domain; solving the solid heat conduction control equation according to the law of conservation of energy to obtain the solid calculation domain temperature field simulation calculation results; using fluid mechanics simulation software to perform flow field simulation calculation on the basic control equation, outputting the fluid calculation domain simulation calculation results, and displaying the dynamic temperature field inside the rotary kiln through simulation.

[0062] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0063] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the relevant technology can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiment.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A cement rotary kiln temperature field simulation calculation method, characterized in that: include: Based on the equipment structure information and production process of cement rotary kiln, the simulation calculation of rotary kiln temperature field is divided into solid calculation domain and fluid calculation domain; Constructing a solid heat conduction control equation for the solid computational domain, and constructing a basic control equation for the fluid computational domain; Solve the solid heat conduction control equation according to the law of conservation of energy to obtain the simulation calculation result of the temperature field in the solid calculation domain; Use fluid mechanics simulation software to perform flow field simulation calculations on the basic control equations, and output simulation calculation results for the fluid calculation domain.

2. The cement rotary kiln temperature field simulation calculation method according to claim 1 is characterized in that: The rotary kiln also includes a coupled calculation domain; In the coupling calculation domain, the raw material is regarded as a fluid, and the flow field simulation calculation of the basic control equation is performed using the partition fluid model of fluid mechanics simulation software, and the simulation calculation results of the coupling calculation domain are output.

3. The cement rotary kiln temperature field simulation calculation method according to claim 1 or 2, characterized in that: The basic control equations include turbulence model, pulverized coal combustion model, radiation model and energy equation source term; The turbulence model, the pulverized coal combustion model, the radiation model and the energy equation source term are coupled and solved, and the simulation calculation results of the fluid calculation domain and / or the simulation calculation results of the coupling calculation domain are output.

4. The cement rotary kiln temperature field simulation calculation method according to claim 1 or 2, characterized in that: The fluid calculation domain simulation calculation results include static simulation calculation results and dynamic prediction results, and the dynamic prediction result calculation method includes: Calculate the initial flow field under steady-state flow process; The combustion process in the kiln is simulated. After the combustion process is stable, the fluid is frozen and the simulation calculation results of the fluid calculation domain are output. The simulation calculation results of the fluid calculation domain include one or more of the gas and material temperature, velocity, and concentration of each gas component inside the rotary kiln.

5. The cement rotary kiln temperature field simulation calculation method according to claim 4 is characterized in that: The simulated kiln combustion process includes: Boundary conditions are set according to the heat exchange amount in the rotary kiln, and the heat exchange amount includes at least one of heat transfer between the flue gas in the kiln and the kiln material through convection and radiation, heat transfer between the flue gas in the kiln and the kiln wall through convection and radiation, heat transfer through heat conduction of the kiln wall covered by the kiln material, heat exchange between the top surface of the kiln material and the uncovered kiln wall through thermal radiation, and heat exchange between the outer wall of the kiln wall and the environment through convection and radiation; The boundary conditions include: the speed and temperature of the primary and secondary air and the kiln head hood pressure are used as the inlet boundary conditions at the kiln head, the flue gas temperature and the smoke chamber pressure are used as the outlet boundary conditions at the kiln tail, the convection radiation mixed boundary conditions are set on the outer wall of the kiln wall, and the kiln wall convection heat transfer coefficient and radiation emission coefficient are estimated by empirical formulas. The coal powder boundary conditions are set through the incident port of the DPM model, and the coal powder boundary conditions include the incident velocity, temperature, mass flow rate, industrial analysis results and particle size distribution of the coal powder; The combustion process in the kiln is simulated based on the boundary conditions.

6. The cement rotary kiln temperature field simulation calculation method according to claim 4 is characterized in that: The simulated kiln combustion process includes: Estimate the length of the decomposition zone, transition zone, sintering zone and cooling zone in the cement rotary kiln, as well as the scope of the raw material area; According to the chemical reactions, components and heat absorption and release of each zone in the decomposition zone, transition zone, sintering zone and cooling zone, boundary parameters are estimated, wherein the boundary parameters include heat absorption and release power, thermal conductivity and specific heat of each zone; The combustion process in the kiln is simulated based on the boundary parameters.

7. The cement rotary kiln temperature field simulation calculation method according to claim 1 is characterized in that: Also includes: According to the temperature field simulation calculation results of the solid calculation domain and the temperature field simulation calculation results of the fluid calculation domain, the external temperature field simulation calculation results of the cement rotary kiln are calculated in combination with the refractory heat transfer calculation of different calculation domains.

8. A cement rotary kiln temperature field simulation calculation device, characterized in that: include: A partitioning module is used to divide the rotary kiln temperature field simulation calculation into a solid calculation domain and a fluid calculation domain based on the equipment structure information and production process of the cement rotary kiln; A construction module, used for constructing a solid heat conduction control equation for the solid calculation domain and a basic control equation for the fluid calculation domain; The first calculation module is used to solve the solid heat conduction control equation according to the law of conservation of energy to obtain the simulation calculation result of the temperature field in the solid calculation domain; The second calculation module is used to use the partition fluid model of fluid mechanics simulation software to perform flow field simulation calculation on the basic control equation and output the simulation calculation results of the fluid calculation domain.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the cement rotary kiln temperature field simulation calculation method as described in any one of claims 1 to 7 is implemented.

10. A non-transitory readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the cement rotary kiln temperature field simulation calculation method as described in any one of claims 1 to 7 is implemented.

Images