A combustion reaction flow operator splitting switching method and system based on splitting distortion risk

Abstract

The present application belongs to the technical field of computational fluid dynamics and combustion numerical simulation, and provides a combustion reaction flow operator splitting switching method and system based on splitting distortion risk, which comprises the following steps: extracting a local monitoring state vector; for each grid cell, constructing a local splitting distortion risk index based on the corresponding local monitoring state vector; identifying high-risk grid cells according to the local splitting distortion risk index of each grid cell and a preset risk threshold, and clustering the high-risk grid cells to form a high-risk connected region; and for the high-risk connected region and the grid cells outside the high-risk connected region, different operator splitting formats are used for time advancement. The present application can accurately identify the high-risk region of splitting distortion prone to misjudgment of ignition and extinction, avoid the calculation redundancy of the global high-precision format, balance the prediction reliability of near-critical combustion phenomena and the overall calculation efficiency, and does not need to modify the existing solver framework, so it has strong engineering practicability.

Description

Technical Field

[0001] This invention belongs to the field of computational fluid dynamics and combustion numerical simulation technology, and relates to a method and system for switching the combustion reactive flow operator based on the risk of splitting distortion. Background Technology

[0002] Numerical simulations of combustion reactive flows typically involve multiple physical processes, including convection, diffusion, and chemical reactions. Chemical reaction terms often exhibit significant nonlinearity and rigidity, while transport processes are closely related to spatial discretization, mesh resolution, and flow timescale. To balance computational efficiency and solution stability, existing combustion reactive flow solvers generally employ operator splitting, decomposing the governing equations into transport and chemical reaction substeps, each advanced using appropriate numerical methods. Among these, the solution framework based on ordinary second-order symmetric splitting (Strang splitting) is widely used due to its simplicity and broad applicability.

[0003] Regarding the aforementioned operator splitting framework, existing technologies have undergone several improvements. Firstly, to reduce the computational cost of complex chemical reactions, dynamic adaptive chemistry methods have been proposed. These methods construct or select locally effective chemical mechanisms online based on the local thermochemical state within the operator splitting framework, thereby reducing the computational cost of reaction substeps. Secondly, to improve numerical accuracy, online estimation of splitting errors and adaptive time step control methods have been proposed, dynamically adjusting the splitting time step based on the error estimation results. Thirdly, addressing the steady-state shifts and ignition / quenching prediction distortions that may occur during Strang splitting under near-critical conditions such as near-ignition and near-quenching, research has proposed steady-state preservation splitting forms such as equilibrium splitting, simplified equilibrium splitting, and well-equilibrium splitting to improve the reliability of near-critical reactive flow calculations. Furthermore, with the development of data-driven methods, research has further explored selecting the ordinary differential equation solver in chemical reaction substeps at the element level and time step level based on the local thermochemical state within the operator splitting framework, aiming to achieve a better trade-off between local errors and computational costs.

[0004] However, existing technologies still have the following shortcomings:

[0005] 1. The main focus is on reducing the cost of chemical calculations, controlling the magnitude of general splitting errors, or optimizing the efficiency of solving local ordinary differential equations. There is a lack of identification and response mechanisms specifically for the "splitting distortion risk". In the near-ignition, near-quenching, and near-combustion mode transition regions, the competition between reaction and transport is significantly enhanced. Relying solely on conventional step-by-step advancement can easily lead to directional or temporal deviations in the prediction of ignition, quenching, flame propagation, or combustion mode transition processes.

[0006] 2. Techniques such as local error estimation, chemical mechanism adaptation, ordinary differential equation solver selection, and steady-state preservation splitting schemes are mostly used independently. Either a high-cost steady-state preservation splitting scheme is uniformly adopted across the entire domain, or only the time step or solver is adjusted. It is impossible to accurately identify high-risk connected regions that "splitting leads to misjudgment of combustion mode" based on local reaction-transport coupling relationships and near-critical characteristics during the same solution process, and to trigger steady-state preservation operator splitting switching and linkage adjustment of integral control parameters only for such regions.

[0007] Therefore, there is an urgent need to propose a numerical solution method that can characterize the risk of local splitting distortion and, based on this, implement local steady-state maintenance operator splitting switching and integral parameter linkage adjustment for high-risk connected regions, so as to ensure the reliability of near-critical combustion region prediction while taking into account overall computational efficiency. Summary of the Invention

[0008] The purpose of this invention is to provide a combustion reactive flow operator splitting switching method and system based on the risk of splitting distortion, so as to solve the technical problems described in the background art where existing operator splitting methods are prone to splitting distortion in the near-critical region and lack accurate identification and local switching linkage mechanisms for high-risk regions.

[0009] This invention constructs a local splitting distortion risk index that comprehensively characterizes the intensity of non-commutative perturbation of the operator, the degree of competition between reaction and transport processes, and the degree of approach to the combustion mode transition boundary. It accurately identifies high-risk connected regions in the computational domain that may experience splitting distortion and triggers steady-state operator splitting schemes and adjusts integral control parameters only in these regions. This improves the reliability and physical rationality of numerical prediction of near-critical combustion regions while taking into account overall computational efficiency.

[0010] To achieve the above objectives, the first aspect of the present invention provides a method for switching the combustion reactive flow operator based on the risk of splitting distortion, comprising the following steps: S1. During the time progression of the numerical simulation of combustion reaction flow, extract the local monitoring state vectors that characterize the combustion state of each grid cell in the current computational domain; S2. For each grid cell, a local splitting distortion risk index is constructed based on the corresponding local monitoring state vector. The local splitting distortion risk index is a comprehensive index constructed based at least on the local non-exchange surrogate index, the local reaction-transport competition index, and the local near-critical weight index, used to quantify the risk of combustion mode prediction deviation generated by the conventional operator splitting scheme at the grid cell. S3. Compare the local splitting distortion risk index of each grid cell with a preset risk threshold, identify high-risk grid cells from each grid cell based on the comparison results, and cluster the high-risk grid cells into high-risk connected regions based on spatial adjacency. S4. For grid cells within the high-risk connected region, trigger a steady-state operator splitting scheme for time advancement and adjust the integral control parameters accordingly; for grid cells outside the high-risk connected region, maintain the conventional operator splitting scheme for time advancement.

[0011] Further, in step S2, for each grid cell, a local splitting distortion risk index is constructed based on the corresponding local monitoring state vector, including: S21. Based on the temperature field gradient and key component mass fraction gradient in the local monitoring state vector of the grid cell, calculate the local non-exchange surrogate index. S22. Based on the amplitude of the local chemical reaction source term and the amplitude of the effective transport flux divergence in the local monitoring state vector of the grid cell, calculate the local reaction-transport competition index. S23. Calculate the local Damcole number based on the local monitoring state vector of the grid cell, and map the local Damcole number to a local near-critical weight index according to a preset near-critical weight function. S24. The local non-exchangeable proxy index, the local reaction-transport competition index, and the local near-critical weight index are weighted and combined according to a preset weight coefficient to generate the local splitting distortion risk index.

[0012] Furthermore, the local non-commutative proxy index characterizes the upper bound of the truncation error caused by the non-commutativity of chemical reaction operators and transport operators in a local region; the local reaction-transport competition index characterizes the relative dominance of chemical reaction rate and matter-energy transport rate; and the local near-critical weight index characterizes the sensitivity of the current grid cell to approaching the ignition mode transition boundary, the flameout mode transition boundary, or the combustion mode transition boundary.

[0013] Further, in step S3, the local splitting distortion risk index of each grid cell is compared with a preset risk threshold, and high-risk grid cells are identified from each grid cell based on the comparison result, including: S31. A dual-threshold hysteresis judgment mechanism is used to compare the local splitting distortion risk index with a preset risk threshold. When the local splitting distortion risk index of a certain grid cell exceeds the preset upper threshold, the grid cell is marked as high-risk. When the local splitting distortion risk index of a grid cell that has been marked as high-risk is lower than the preset lower threshold, the high-risk label of the grid cell is removed. The lower threshold is less than the upper threshold. S32. Perform spatial connectivity clustering on all grid cells in a high-risk state at the current moment, and merge spatially adjacent high-risk grid cells into the same high-risk connectivity region; S33. Extend a preset number of grid cells outward from each of the high-risk connected regions as a buffer layer, and include the grid cells in the buffer layer into the corresponding high-risk connected regions.

[0014] Furthermore, in step S4, the linkage adjustment of the integral control parameters includes at least one of the following: Increase the maximum allowed number of iterations for chemical reaction sub-cycles within the high-risk connected regions; Tighten the local error tolerance coefficient of the chemical reaction solver in the high-risk connected region.

[0015] Furthermore, at the boundary interface between the high-risk connected region and its adjacent grid cells, spatial weighted interpolation is performed on the integral control parameters to ensure a continuous transition of the integral control parameters when crossing the boundary interface.

[0016] Further, in step S4, the steady-state preserved operator splitting scheme is selected from one of the balanced operator splitting scheme, the simplified balanced operator splitting scheme, or the well-balanced operator splitting scheme; the conventional operator splitting scheme is selected from one of the standard Lie-Trotter splitting scheme or the Strang splitting scheme.

[0017] Furthermore, the method also includes: S5. After each time step is completed, state synchronization processing is performed on the boundary interface between the high-risk connected region and its adjacent grid cells, and conservation quantity correction and update are performed on the global computation domain to ensure the conservation of mass, momentum and energy of the cross-region interface.

[0018] A second aspect of the present invention provides a combustion reaction flow operator splitting switching system based on splitting distortion risk, including a state monitoring module, a risk assessment module, a region identification module, and a splitting control module.

[0019] Among them, the state monitoring module is used to extract local monitoring state vectors that characterize the combustion state of each grid cell in the current computational domain during the time progression of the numerical simulation of combustion reaction flow; The risk assessment module is used to construct a local splitting distortion risk index for each grid cell based on the corresponding local monitoring state vector. The local splitting distortion risk index is a comprehensive index constructed based at least on the local non-exchange surrogate index, the local reaction-transport competition index, and the local near-critical weight index, which is used to quantify the risk of combustion mode prediction deviation generated by the conventional operator splitting scheme at the grid cell. The region identification module is used to compare the local splitting distortion risk index of each grid cell with a preset risk threshold, identify high-risk grid cells from each grid cell based on the comparison results, and cluster the high-risk grid cells into high-risk connected regions based on spatial adjacency. The split control module is used to trigger a steady-state operator splitting scheme for time advancement for grid cells within the high-risk connected region and adjust the integral control parameters accordingly; for grid cells outside the high-risk connected region, it maintains the conventional operator splitting scheme for time advancement.

[0020] Furthermore, the system also includes a memory and a boundary processing and update module.

[0021] The memory is used to store a preset risk threshold configuration table corresponding to the local splitting distortion risk index; The boundary processing and update module is used to perform state synchronization processing on the boundary interface between the high-risk connected region and its adjacent grid cells after each time step is completed, and to perform conservation quantity correction update on the global computation domain to ensure the conservation of mass, momentum and energy of the cross-region interface.

[0022] In the numerical solution of combustion reactive flow using a chemical reaction-transport operator splitting framework, this invention identifies high-risk connected regions by constructing a local splitting distortion risk index (also known as a composite splitting distortion risk index), and triggers a steady-state-preserving operator splitting scheme and a linked adjustment of integral control parameters. This method is particularly suitable for simulating combustion reactive flow involving detailed chemical mechanisms, rigid multi-step chemical mechanisms, or other processes with significant multi-timescale coupling characteristics.

[0023] Compared with the prior art, the present invention has at least the following advantages: 1. Risk identification targets are more physically targeted, effectively avoiding misjudgment of combustion modes. Existing adaptive methods mostly focus on reducing the computational cost of chemical reactions or controlling general time integration errors, failing to distinguish between "high reactivity" and "high risk of splitting distortion." This invention directly addresses the specific technical problem of "ignition / extinguishing / mode transition judgment deviation caused by the stepwise progression of reaction-transport." By identifying local splitting distortion risk areas for precise response, it fundamentally solves the problem of over- or under-protection caused by traditional methods simply equating high-temperature, high-gradient regions with high-risk regions, significantly improving the reliability of predicting key combustion phenomena.

[0024] 2. A scientifically constructed multidimensional coupling risk index enhances the accuracy of high-risk identification. This invention abandons the one-sided evaluation method relying on a single reaction rate or rigid index, and innovatively constructs a local splitting distortion risk index that integrates three-dimensional features: local non-commutativity surrogate, reaction-transport competition, and near-critical weights. This index simultaneously characterizes the upper bound of operator non-commutativity truncation error, the competitive relationship of reaction-transport dominant mechanisms, and the sensitivity of mode transition boundaries. It can accurately reflect the physical nature of "reaction-transport coupling distortion" in combustion reaction flow, effectively filter false high-risk signals in non-critical areas, and make format switching decisions more accurate and reliable.

[0025] 3. The regionalized adaptive switching mechanism balances accuracy and efficiency, demonstrating strong engineering applicability. This invention overcomes the computational bottleneck of uniformly adopting a steady-state-preserving splitting scheme across the entire domain. It triggers a high-precision scheme and tightens the integration parameters only within identified high-risk connected regions, achieving on-demand allocation of computational resources. Compared to the global high-precision method, it significantly reduces the overall computational overhead while ensuring numerical stability in near-critical regions. Compared to independent switching at the unit level, the switching strategy based on connected region clustering avoids numerical discontinuities and parallel synchronization difficulties caused by frequent scheme jumps, significantly improving the algorithm's engineering stability and scalability.

[0026] 4. The non-intrusive modular design offers excellent compatibility and easy embedding into existing solvers. This invention does not require changes to the basic governing equations and overall step-by-step framework of existing combustion-reactive flow solvers; functional upgrades can be achieved simply by adding risk identification, region clustering, and format switching modules. This design is fully compatible with conventional operator splitting frameworks, local reaction integration methods, and various chemical mechanism handling strategies. It is suitable for both rigid and complex combustion simulations involving detailed chemical mechanisms and other reactive flow scenarios with significant reaction-transport competition characteristics, demonstrating a clear modification path and broad engineering application value. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments 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.

[0028] Figure 1 This is a flowchart of the combustion reactive flow operator splitting and switching method based on the risk of splitting distortion according to the present invention; Figure 2 This is an architecture diagram of the combustion reactive flow operator splitting and switching system based on the risk of splitting distortion, as described in this invention. Figure 3 This is a schematic diagram of the execution flow of the combustion reactive flow operator splitting and switching based on the risk of splitting distortion in this invention; Among them, 201 is the status monitoring module; 202 is the risk assessment module; 203 is the area identification module; 204 is the split control module; 205 is the memory; and 206 is the boundary processing and update module. Detailed Implementation

[0029] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0030] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. This application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, in the absence of conflict, the following embodiments and features of the embodiments can be combined with each other. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0031] like Figure 1 As shown, this embodiment of the invention provides a combustion reactive flow operator splitting switching method based on splitting distortion risk, including the following steps: S1. During the time progression of the numerical simulation of combustion reaction flow, extract the local monitoring state vector that characterizes the combustion state of each grid cell in the current computational domain.

[0032] The local monitoring state vector includes at least a combination of the following physical quantities: local temperature, concentration of key progress variables, high-temperature reaction marker, low-temperature reaction marker, mixture fraction, and variance. The high-temperature and low-temperature reaction markers are extracted from the local thermochemical state based on preset temperature or reaction rate thresholds, respectively.

[0033] S2. For each grid cell, a local splitting distortion risk index is constructed based on the corresponding local monitoring state vector. The local splitting distortion risk index is a comprehensive index constructed based at least on the local non-exchange surrogate index, the local reaction-transport competition index, and the local near-critical weight index, used to quantify the risk of combustion mode prediction bias generated by the conventional operator splitting scheme at the grid cell.

[0034] Specifically, the construction process for the local splitting distortion risk index of each grid cell includes the following steps: S21. Based on the temperature field gradient and key component mass fraction gradient in the local monitoring state vector of the grid cell, calculate the local noncommutative surrogate index. This local noncommutative surrogate index characterizes the upper bound of the truncation error caused by the noncommutativity of the chemical reaction operator and the transport operator in the local region. Its magnitude is positively correlated with the degree of spatial nonparallelism of the temperature field gradient and the key component mass fraction gradient, and positively correlated with the larger of the amplitude of the local chemical reaction source term and the amplitude of the effective transport flux divergence.

[0035] S22. Based on the amplitude of the local chemical reaction source term and the amplitude of the effective transport flux divergence in the local monitoring state vector of the grid cell, calculate the local reaction-transport competition index. This local reaction-transport competition index characterizes the relative dominance of the chemical reaction rate and the mass-energy transport rate. It is a dimensionless ratio function of the amplitude of the local chemical reaction source term and the amplitude of the effective transport flux divergence, wherein the amplitude of the effective transport flux divergence includes at least the contributions of component diffusion flux divergence and heat conduction flux divergence.

[0036] S23. Calculate the local Damcole number based on the local monitoring state vector of the grid cell, and map the local Damcole number to a local near-critical weight index according to a preset near-critical weight function. This local near-critical weight index characterizes the sensitivity of the current grid cell to approaching the ignition mode transition boundary, the flameout mode transition boundary, or the combustion mode transition boundary.

[0037] In specific implementation, the near-critical weighting function is a monotonically increasing function with the local Damcole number as the independent variable, and the rate of change within the preset critical Damcole number neighborhood is greater than the rate of change within the stable combustion range far from the critical Damcole number; the specific form of the near-critical weighting function is an S-shaped response curve or a piecewise linear response curve; when the local Damcole number is in the stable combustion range far from the critical region, the local near-critical weighting index outputs a low weight value lower than the first preset threshold; when the local Damcole number enters the neighborhood of the critical Damcole number, the local near-critical weighting index increases to a high weight value higher than the second preset threshold as the local Damcole number approaches the critical value; wherein the second preset threshold is greater than the first preset threshold.

[0038] S24. The local non-exchangeable proxy index, the local reaction-transport competition index, and the local near-critical weight index are weighted and combined according to a preset weight coefficient to generate the local splitting distortion risk index.

[0039] In practice, the weighted combination satisfies the following rules: The preset weight coefficients include a first weight corresponding to the local non-exchangeable proxy index, a second weight corresponding to the local reaction-transport competition index, and a third weight corresponding to the local near-critical weight index, wherein the sum of the first weight, the second weight, and the third weight is 1; The local non-commutative proxy index and the local reaction-transport competition index are normalized to become dimensionless quantities before weighted combination; the normalization process adopts one of the following methods: normalization is performed with the maximum value of the entire computational domain within the current time step as the reference scale, or adaptive normalization is performed with the exponential moving average statistic based on historical time steps as the reference scale.

[0040] S3. Compare the local splitting distortion risk index of each grid cell with a preset risk threshold, identify high-risk grid cells from each grid cell based on the comparison results, and cluster the high-risk grid cells into high-risk connected regions based on spatial adjacency.

[0041] Specifically, the identification of high-risk grid cells within each grid cell includes the following steps: S31. A dual-threshold hysteresis judgment mechanism is used to compare the local splitting distortion risk index with a preset risk threshold. When the local splitting distortion risk index of a certain grid cell exceeds the preset upper threshold, the grid cell is marked as high-risk. When the local splitting distortion risk index of a grid cell that has been marked as high-risk is lower than the preset lower threshold, the high-risk label of the grid cell is removed. The lower threshold is less than the upper threshold. S32. Perform spatial connectivity clustering on all grid cells in a high-risk state at the current moment, and merge spatially adjacent high-risk grid cells into the same high-risk connectivity region; S33. Extend a preset number of grid cells outward from each of the high-risk connected regions as a buffer layer, and include the grid cells in the buffer layer into the corresponding high-risk connected regions.

[0042] The preset number of layers is a buffer layer number determined adaptively, and the determination method is as follows: Calculate the spatial gradient magnitude of the local split distortion risk index at the boundary of the high-risk connected region; when the spatial gradient magnitude is greater than a preset gradient threshold, set the number of buffer layers to the first layer value; when the spatial gradient magnitude is less than or equal to the preset gradient threshold, set the number of buffer layers to the second layer value; wherein, the first layer value is greater than the second layer value.

[0043] S4. For grid cells within the high-risk connected region, trigger a steady-state operator splitting scheme for time advancement and adjust the integral control parameters accordingly; for grid cells outside the high-risk connected region, maintain the conventional operator splitting scheme for time advancement.

[0044] The linkage adjustment integral control parameter includes at least one of the following: 1) Increase the maximum allowed number of iterations for chemical reaction sub-cycles within the high-risk connected regions; 2) Tighten the local error tolerance coefficient of the chemical reaction solver in the high-risk connected region.

[0045] Furthermore, when adjusting the integral control parameters in a coordinated manner, spatial weighted interpolation is performed on the integral control parameters at the boundary interface between the high-risk connected region and its adjacent grid cells, so that the integral control parameters transition continuously when crossing the boundary interface, wherein the weight coefficient of the spatial weighted interpolation is determined based on the normal distance from the grid cell to the boundary interface.

[0046] In an optional embodiment of step S4, the steady-state preserving operator splitting scheme is selected from one of a balanced operator splitting scheme, a simplified balanced operator splitting scheme, or a well-balanced operator splitting scheme. The conventional operator splitting scheme is selected from one of a standard Lie-Trotter splitting scheme or a Strang splitting scheme.

[0047] In an improved embodiment of the above method, the method further includes: S5. After each time step is completed, state synchronization processing is performed on the boundary interface between the high-risk connected region and its adjacent grid cells, and conservation quantity correction and update are performed on the global computation domain to ensure the conservation of mass, momentum and energy of the cross-region interface.

[0048] Based on the same inventive concept, this invention also provides a combustion reactive flow operator splitting and switching system based on splitting distortion risk, as described in the following embodiments. Since the principle of the combustion reactive flow operator splitting and switching system based on splitting distortion risk is similar to the combustion reactive flow operator splitting and switching method based on splitting distortion risk disclosed in the above embodiments, the implementation of the combustion reactive flow operator splitting and switching system based on splitting distortion risk can refer to the implementation of the combustion reactive flow operator splitting and switching method based on splitting distortion risk, and repeated details will not be elaborated further. As used below, the terms "unit" or "module" can refer to a combination of software and / or hardware that performs a predetermined function. Although the apparatus described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0049] Figure 2 This is a structural block diagram of a combustion reactive flow operator splitting and switching system based on splitting distortion risk disclosed in an embodiment of the present invention, as shown below. Figure 2 As shown, the system includes a status monitoring module 201, a risk assessment module 202, an area identification module 203, and a split control module 204. The following description, in conjunction with the appendix... Figure 3 The structure is described below.

[0050] During operation, the combustion reaction flow control equations of this invention are spatially discretized using the finite volume method, and the time progression employs a chemical reaction-transport operator splitting framework. For any local state within the control volume, its discretized time evolution can be written as: ; in, This is a local monitoring state vector; For the input operator, it represents the rate of state change caused by both convection and diffusion; This is the action term of the reaction operator, representing the rate of change of state caused by the chemical reaction; For time.

[0051] In normal regions, a conventional second-order symmetric splitting scheme is used for propagation; in high-risk regions, a steady-state preservation splitting scheme is used. Preferably, the propagation form in normal regions is written as: ; in, and They represent the first The time step and the first The local state at each time step; This is the global time step. To advance the operator for transport substeps; This is the reactive substep propagation operator. The above form corresponds to the conventional second-order symmetric split propagation method.

[0052] For high-risk areas, a steady-state maintenance-type splitting propulsion approach is adopted, which can be summarized as follows: ; in, This represents a steady-state-preserving split propulsion operator; This represents the set of reaction integral parameters within a high-risk region, including at least the number of reaction subcycles, relative error tolerance, absolute error tolerance, and Jacobian matrix update frequency.

[0053] The core of this invention does not lie in changing the spatial discretization method of the control equations, but rather in: while keeping the original control equations and basic solution framework unchanged, by identifying the risk of local splitting distortion, a more robust time-progression organization method is implemented only for high-risk regions.

[0054] In one embodiment of the state monitoring module 201, this module is used to extract local monitoring state vectors characterizing the combustion state of each grid cell within the current computational domain during the time progression of the combustion reaction flow numerical simulation. To reduce the computational overhead of risk identification while ensuring the criteria have sufficient representativeness of combustion physics, this embodiment does not directly establish risk criteria for all state variables. Instead, the state monitoring module 201 constructs local state vectors for risk monitoring. These local monitoring state vectors can be expressed as: ; in, For temperature; As a progress variable, it is used to characterize the local combustion process; This is a marker quantity for high-temperature reactions; This is a marker quantity for low-temperature or intermediate-temperature reactions. For combustion systems that do not have a distinct low-temperature chemical phase, Alternatively, another representative variable that can reflect changes in local reactivity can be selected, such as the second type of key free radical, key intermediate product, or local exothermic characteristic quantity.

[0055] In some preferred embodiments, the progress variable It can be defined as a weighted normalized combination of the mass fractions of several product components, active components, or key intermediate products, i.e.: ; in, For the first Mass fraction of each component; This is the weighting coefficient of this component in the progress variable; The number of components involved in constructing the progress variable; For the initial state, the first Mass fraction of each component; For reference to the burnout state, equilibrium state, or target final state, the first Mass fraction of each component.

[0056] The purpose of using the aforementioned local monitoring state vector in this invention is twofold: first, to characterize the degree of local combustion development more stably through temperature and progress variables; and second, to further enhance the ability to distinguish different combustion stages, different reactive zones, and different mode transition zones by adding the above two types of reaction markers, thereby avoiding the high computational cost brought about by relying entirely on the state variables of all components.

[0057] In one embodiment of the risk assessment module 202, the module is used to construct a local splitting distortion risk index for each grid cell based on the corresponding local monitoring state vector. The local splitting distortion risk index is a comprehensive index constructed based at least on the local non-exchange surrogate index, the local reaction-transport competition index, and the local near-critical weight index, used to quantify the risk of combustion mode prediction bias generated by the conventional operator splitting scheme at the grid cell.

[0058] In some preferred embodiments, the risk assessment module includes a risk index calculation unit and a normalization processing unit. The output of the risk index calculation unit is communicatively connected to the input of the normalization processing unit. The risk index calculation unit includes a local non-exchangeable proxy index calculation unit, a local reaction-transport competition index calculation unit, a local near-critical weight index calculation unit, and a weighted calculation unit.

[0059] In practice, at each time step At the beginning, the local states within each control volume are first obtained from the current discrete flow field. Then, the basic increments of the input operator and reaction operator on the local monitoring state vector within the current time step are calculated respectively. Let the global time step be... Then the definition is: ; in, This represents the local increment of the monitored state vector by the reaction operator within a global time step; This represents the local increment of the monitored state vector by the input operator within a global time step.

[0060] 1) Local non-exchangeable proxy index calculation unit To characterize the degree of mutual perturbation between the reaction operator and the input operator in the current local state, a local noncommutative surrogate index is constructed: ; in, For local non-exchangeable proxy metrics; For weighted norm; To prevent small positive quantities with a denominator of zero.

[0061] The physical meaning of the above indicators is as follows: if the response of the reaction operator is significantly different from that of the reaction operator in the original state after the transport perturbation is applied first, or if the response of the transport operator is significantly different from that of the transport operator in the original state after the reaction perturbation is applied first, it indicates that the step-by-step advancement of the reaction and transport in the current local state has strong non-commutative characteristics. That is, the advancement order and step-by-step mode may significantly affect the local evolution results. At this time, the structural risk of splitting distortion is high.

[0062] In this embodiment, the weighted norm is preferably in the form of a quadratic form: ; in, Let be the vector to be measured; For the vector of the first One component; To monitor the number of components in the state vector; These are the normalized weights for the corresponding components. For the four-dimensional monitoring state vector given above, Weight The purpose of this setting is to eliminate the influence of differences in the dimensions and numerical amplitudes of different variables on the norm calculation. Preferably, the weights of temperature, progression variables, and the two types of response markers can be set according to their reference amplitudes, mean square fluctuation levels, or statistical characteristics of the pre-calculated sample.

[0063] 2) Local Response - Transport Competition Index Calculation Unit Non-exchange agent indicators alone are insufficient to distinguish the areas that truly require protection. Therefore, this implementation further constructs a local reaction-transport competition index. First, the local reaction contribution intensity and the local transport contribution intensity are defined as follows: ; in, It contributes to the intensity of local reactions; It contributes intensity to local transport.

[0064] Based on this, the local reaction-transport competition index is defined as: ; in, The value range is from 0 to 1. When and When the magnitudes are close, Close to 1; when one factor is clearly dominant, It is close to 0.

[0065] The purpose of this indicator is to limit high-risk identification to regions where both reaction and transport play a significant role, rather than simply considering all high-temperature regions, high-reaction-rate regions, or high-gradient regions as high-risk areas. In other words, only when a local region simultaneously exhibits significant non-exchange characteristics and a strong reaction-transport competition relationship is it more worthy to trigger steady-state preservation-type splitting protection.

[0066] 3) Local near-critical weight index calculation unit To further characterize whether the local state is close to the boundary of ignition, flameout, or combustion mode transition, this embodiment introduces a near-critical weight based on the local Damköhler number. For the progress variable... Define the local chemical timescale and the local mixing timescale respectively: ; in, For local chemical timescales; For local mixing timescales; This represents the rate of change of the progress variable under the action of the reaction operator; It represents the rate of change of the progress variable under the action of the input operator.

[0067] Therefore, the local Damköhler number is defined as follows: ; in, For the local Damköhler number. When At that time, the local process tends to be reaction-driven; when At that time, the local process tends to be transport-dominated; when This indicates that the reaction and transport are on similar timescales, and the local state is more susceptible to numerical perturbations.

[0068] To highlight the risk weights in the near-critical region, the following definitions are further provided: ; in, Near-critical weights; This is a positive parameter used to control the width of the near-critical sensitive region. This weight is... It takes a larger value initially, and gradually decreases when it deviates significantly from the condition.

[0069] 4) The weighted calculation unit calculates the local splitting distortion risk index. After obtaining the above three quantities, a composite risk index for local splitting distortion is constructed. ; in, This is a composite risk indicator for localized splitting distortion. and This is an adjustment parameter between 0 and 1, used to control the strength of the impact of competition and near-critical weights on total risk.

[0070] The construction principle of this composite index is that the risk index only increases significantly when the following conditions are met simultaneously in a local area: there is a significant non-exchange effect between the reaction operator and the transport operator; the reaction and transport compete significantly in the local space; and the local state is close to the boundary of ignition, flameout, or mode transition. Therefore, the area identified by this invention is not a "large error region" or "high temperature region" in the general sense, but rather a high-risk region that is more likely to be misjudged due to conventional step-by-step propagation.

[0071] In one embodiment of the region identification module 203, the module is used to compare the local splitting distortion risk index of each grid cell with a preset risk threshold, identify high-risk grid cells from each grid cell according to the comparison result, and cluster the high-risk grid cells into high-risk connected regions based on spatial adjacency.

[0072] In practice, this module is used to identify high-risk areas and form connected domains.

[0073] To avoid frequent oscillations of high-risk states in adjacent time steps, this implementation method employs a dual-threshold hysteresis determination approach. A high threshold is set... and low threshold ,in For any control body, define a high-risk indicator function. for: ; in, Indicates the center position of the control volume; and These represent the high-risk state markers of the previous time step and the current time step, respectively; when This indicates that the control unit belongs to a high-risk unit.

[0074] After obtaining the set of high-risk cells, instead of directly switching the splitting scheme for each cell, we cluster connected components based on spatial adjacency relationships to form one or more high-risk connected regions. For two-dimensional meshes, the four-adjacency or eight-adjacency criterion can be used; for three-dimensional meshes, the six-adjacency or twenty-six-adjacency criterion can be used. To reduce potential local numerical discontinuities at region switching boundaries, one or two adjacent control volumes can be extended along the outer boundary of the formed high-risk connected regions as a buffer layer. Let the original high-risk region be... The final high-risk area after the buffer layer expansion is denoted as The number of buffer layers can be a fixed preset value, or it can be adaptively determined based on the spatial gradient magnitude of the comprehensive risk index at the boundary of the high-risk connected region: the larger the gradient magnitude, the more drastic the risk change, and the thicker the buffer layer is needed for a smooth transition.

[0075] By adopting a holistic approach to connected regions, we can reduce the implementation complexity and parallel synchronization difficulties caused by frequent switching at the unit level, and also improve the spatiotemporal continuity at the interface of local split format switching.

[0076] In one embodiment of the split control module 204, the module is used to trigger a steady-state operator splitting scheme for time advancement for grid cells within the high-risk connected region and adjust the integral control parameters accordingly; for grid cells outside the high-risk connected region, the module maintains a conventional operator splitting scheme for time advancement.

[0077] In practice, different time-based organizational methods will be adopted for ordinary areas and high-risk areas. For ordinary areas... The original conventional second-order symmetric splitting propagation method was chosen; however, for high-risk areas... It switches to a steady-state, split-propellant mode. This can be written in a unified form as: ; in, This indicates the conventional splitting propagation operator used in the ordinary region; This indicates the steady-state-preserving split propulsion operator used in high-risk areas; For the entire computational domain; This is a high-risk connectivity area; This is the set of reaction integral parameters for high-risk areas.

[0078] Steady-state preservation splitting schemes can be balanced splitting, simplified balanced splitting, well-balanced splitting, or other splitting forms with steady-state preservation characteristics. Conventional second-order symmetric splitting schemes can be either the standard Lie-Trotter splitting scheme or the Strang splitting scheme.

[0079] In one preferred embodiment, conventional second-order symmetric splitting is used in ordinary regions, and simplified balanced splitting is used in high-risk regions; in another embodiment, a well-balanced splitting form can also be selected based on the existing structure of the solver.

[0080] To further improve the stability of the reaction integral in the high-risk region, this implementation method simultaneously tightens the reaction integral parameters in the high-risk region during the splitting scheme switching. Let the number of reaction sub-cycles in the normal region be... The number of reaction subcycles in the high-risk area is Then it is acceptable: ; in, It is a positive integer used to control the amount of additional sub-loops added in high-risk areas; This is a high-risk indicator function. When the control body is located in a high-risk area... Increase the number of reactant loops; otherwise, keep the default value.

[0081] Correspondingly, the cycle step size of individual reactants in high-risk regions It can be written as: ; Furthermore, the relative and absolute error tolerances of the reaction integrator can also be tightened simultaneously. For example, let the relative and absolute error tolerances in the normal region be respectively... and In high-risk areas, the following can be selected: ; in, and These are the relative error tolerance and absolute error tolerance within the high-risk area, respectively. and The tightening coefficient is between 0 and 1. Preferably, and Less than 1, to improve the accuracy of reaction integrals in high-risk areas.

[0082] For rigid reaction integrators employing Jacobian matrices, the update frequency of the Jacobian matrix can be increased in high-risk regions. If the solver is equipped with multiple reaction integration methods, a more robust reaction integration strategy can be switched to in high-risk regions. It should be noted that the above-mentioned linkage tightening measures are auxiliary measures in this invention, and their core is still: based on the local splitting distortion risk index, steady-state maintenance-type splitting switching is only implemented in high-risk regions.

[0083] In practical implementation, this embodiment provides the following preferred setting principles for the main parameters to facilitate actual implementation.

[0084] For the weights in the weighted norm It is advisable to normalize the settings based on the reference amplitude, mean square fluctuation level, or sample statistical standard deviation of each monitored variable to avoid imbalances in risk indicators caused by dimensional differences among temperature, progression variables, and response markers. and Their main functions are to adjust the influence of competition level and near-critical weight on total risk, respectively. Preferably, and The risk indicators can be preset based on sensitivity analysis of the risk index distribution under baseline operating conditions; when it is desirable to emphasize the importance of the near-critical transition zone, the settings can be appropriately reduced. When it is desirable to more strictly limit the concentration of risk in the reaction-transport competition zone, the concentration can be appropriately reduced. .

[0085] For parameters in near-critical weights Its control The width of the sensitive region when it is close to 1. If If the value is too small, only a very few regions will obtain a large near-critical weight; if If the value is too large, the distinguishing ability of the near-critical weight decreases. Therefore, It is advisable to combine typical working conditions The statistical distribution is pre-defined.

[0086] For high and low risk thresholds and Preferably, it can be based on several benchmark operating conditions. The probability distribution is selected to keep the volume fraction of the computational domain occupied by the high-risk region within a controllable range, thus covering the true near-critical high-risk region without significantly expanding the application scope of steady-state-preserving splitting. Generally speaking, Used to trigger the switch. When switching off, an appropriate interval should be maintained between the two to avoid frequent switching of risk states between adjacent time steps.

[0087] The increase in the number of reactant cycles in high-risk areas Tolerance tightening factor , The number of buffer layers can be set comprehensively based on accuracy requirements, mesh scale, mechanistic rigidity, and computational resources. This invention does not require the above parameters to use unique fixed values, but emphasizes that their settings should follow the principle of "maintaining efficiency in ordinary areas and strengthening protection in high-risk areas."

[0088] In an optional embodiment, such as Figure 2 As shown, the system also includes a memory 205, which is used to store a preset risk threshold configuration table corresponding to the local splitting distortion risk index.

[0089] In an optional embodiment, such as Figure 2 and Figure 3 As shown, the system also includes a memory 205 and a boundary processing and update module 206. This module is used to perform state synchronization processing on the boundary interface between the high-risk connected region and its adjacent grid cells after each time step is completed, and to perform conservation quantity correction update on the global computational domain to ensure the conservation of mass, momentum and energy of the cross-region interface.

[0090] In practice, since high-risk areas and ordinary areas use different time-progression organization methods within the same time step, it is necessary to handle the state synchronization problem between the two at the area boundaries. Preferably, the area boundary synchronization is handled as follows: First, based on the expanded high-risk area... One or two layers of buffer control are introduced to smooth the propulsion differences at the boundaries of regions. Secondly, after completing the sub-step propulsion of high-risk regions and ordinary regions, a unified global conservation update stage is entered to ensure that the updates of mass, momentum, energy and component transport still satisfy the conservation structure of the original solver. Finally, the updated state is written back to the global field for risk identification and propulsion control in the next time step.

[0091] The following is an exemplary embodiment of the present invention, used to illustrate the implementation and technical effects of the present invention, but it is not intended to limit the scope of the present invention.

[0092] Example 1: A transient case of a two-dimensional near-critical counter-diffusion flame was selected as the verification object. The computational domain was a two-dimensional rectangular region with oxidizer and fuel inlets at the upper and lower boundaries, respectively. The inflows from both sides formed a counter-mixing and reaction zone in the central region. First, a set of steady-state flame solutions close to the extinction boundary was obtained as the initial field. Based on this, reignition and local extinction competition processes were triggered by inlet velocity perturbation, inlet temperature perturbation, or local high-temperature perturbation, so that near-critical evolution behavior that is sensitive to both ignition timing and extinction location appeared simultaneously in the computational domain. The governing equations were discretized using the finite volume method, and the time progression adopted a chemical reaction-transport operator splitting framework. Temperature was taken as... Progress variables A high-temperature reaction marker and a low-temperature or medium-temperature reaction marker This constitutes the monitoring state vector. Conventional second-order symmetric split propulsion is used in ordinary areas, while simplified balanced split propulsion is used in high-risk areas. The calculations for each control volume are performed using the aforementioned method. , , and It also utilizes dual-threshold hysteresis determination and connected component clustering to identify high-risk areas.

[0093] In this embodiment, the method of the present invention is compared with the following two types of benchmark calculations: 1. Baseline Method A: The calculation results of conventional second-order symmetric splitting (Strang splitting) are uniformly adopted across the entire domain, representing a scheme with low computational cost but weak reliability in predicting near-critical events; 2. Baseline Method B: The entire domain adopts a steady-state preservation type split (simplified equilibrium type split), which represents a scheme with higher prediction reliability but higher overall computational cost; When making comparisons, the following quantities need to be considered: ignition timing, quenching location, propagation location of the local high-temperature reaction zone, evolution trend of progression variables within the near-transition zone, and total computation time. For example, the relative error of ignition timing, quenching location deviation, volume fraction of high-risk area, and computation time ratio can be used as evaluation indicators, defined as follows: ; ; ; ; in, The ignition timing is when the method of the present invention or the method to be compared is used; The ignition timing is referenced to the high-precision solution. The flameout position is obtained by the method to be compared. The reference high-precision solution corresponds to the shutdown position; For reference length; The volume or area of ​​the high-risk area; The volume or area of ​​the entire computational domain; The computation time of the method of the present invention or the method to be compared; The computation time is for the conventional second-order symmetric splitting method across the entire domain. The reference high-precision solution is a unified numerical benchmark solution used for comparison and evaluation, applicable to error calculations of benchmark method A, benchmark method B, and the method of this invention. Preferably, the reference high-precision solution is obtained under the same spatial discretization scheme, the same physical model, and the same boundary conditions by employing a smaller time step, a globally steady-state-preserving splitting scheme, and a more stringent reaction integral tolerance; if necessary, it can also be further combined with finer mesh results for consistency verification. See Table 1 below for a performance comparison of different methods in near-critical combustion simulations: Table 1: Performance Comparison Results of Different Methods in Near-Critical Combustion Simulation

[0094] As can be seen from Table 1 above: 1. Compared with the baseline method A, the method of the present invention reduces the relative error of ignition timing by approximately two orders of magnitude (from 1.6 × 10⁻⁶) at the cost of increasing computation time by 52%. -2 Reduced to 1.2×10 -4 The method significantly reduced the flameout position deviation from 6.8% to 1.4%, indicating that the method of the present invention can significantly improve the predictive reliability of critical combustion events in the near-critical region.

[0095] 2. Compared with the baseline method B, the method of the present invention maintains a relatively close prediction accuracy (ignition error is 1.2 × 10⁻⁶). -3 and 7.0×10 -4Under the premise of quench deviations of 1.4% and 0.9% respectively, the overall computation time is only about half that of the benchmark method B (1.52 and 3.10) because the high-cost steady-state maintenance splitting is only used in the identified high-risk connected regions (accounting for 11% of the computational domain volume). This shows that the method of the present invention has a significant computational efficiency advantage while maintaining high prediction reliability.

[0096] In summary, this embodiment clearly demonstrates through quantitative indicators that the method of the present invention has successfully achieved the expected technical effect of "focusing on the protection of high-risk areas and maintaining efficiency in ordinary areas," while effectively controlling the overall computational cost while ensuring the reliability of the prediction of near-critical key combustion phenomena.

[0097] This invention achieves targeted control of local splitting distortion risk in combustion reaction flow through a closed-loop process of "local state extraction - composite risk calculation - high-risk area identification - steady-state maintenance type splitting switching - linkage integral control - global synchronous update", and has a clear implementation path and engineering operability.

[0098] In this embodiment, a computer device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements any of the above-mentioned combustion reactive flow operator splitting switching methods based on splitting distortion risk.

[0099] Specifically, the computer device can be a computer terminal, a server, or a similar computing device.

[0100] In this embodiment, a computer-readable storage medium is provided, which stores a computer program that executes any of the above-described combustion reactive flow operator splitting switching methods based on splitting distortion risk.

[0101] Specifically, computer-readable storage media, including both permanent and non-permanent, removable and non-removable media, can store information using any method or technology. Information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer-readable storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable storage media does not include transient media, such as modulated data signals and carrier waves.

[0102] Obviously, those skilled in the art should understand that the modules or steps of the above-described embodiments of the present invention can be implemented using general-purpose computing devices. They can be centralized on a single computing device or distributed across a network of multiple computing devices. Optionally, they can be implemented using computer-executable program code, thereby storing them in a storage device for execution by a computing device. In some cases, the steps shown or described can be performed in a different order than those presented here, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Thus, the embodiments of the present invention are not limited to any particular hardware and software combination.

[0103] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, various modifications and variations of the embodiments of the present invention are possible. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for switching the splitting of a combustion reactive flow operator based on the risk of splitting distortion, characterized in that, include: During the time progression of the numerical simulation of combustion reaction flow, local monitoring state vectors characterizing the combustion state of each grid cell in the current computational domain are extracted; For each grid cell, a local splitting distortion risk index is constructed based on the corresponding local monitoring state vector. The local splitting distortion risk index is a comprehensive index constructed based at least on the local non-exchange surrogate index, the local reaction-transport competition index, and the local near-critical weight index, used to quantify the risk of combustion mode prediction bias generated by the conventional operator splitting scheme at the grid cell. The local splitting distortion risk index of each grid cell is compared with a preset risk threshold. Based on the comparison results, high-risk grid cells are identified from each grid cell, and high-risk grid cells are clustered into high-risk connected regions based on spatial adjacency. For grid cells within the high-risk connected regions, a steady-state operator splitting scheme is triggered for time advancement, and the integral control parameters are adjusted accordingly; for grid cells outside the high-risk connected regions, a conventional operator splitting scheme is maintained for time advancement.

2. The combustion reactive flow operator splitting and switching method based on splitting distortion risk according to claim 1, characterized in that, For each grid cell, a local splitting distortion risk index is constructed based on the corresponding local monitoring state vector, including: Based on the temperature field gradient and key component mass fraction gradient in the local monitoring state vector of the grid cell, the local non-exchange surrogate index is calculated. Based on the amplitude of the local chemical reaction source term and the amplitude of the effective transport flux divergence in the local monitoring state vector of the grid cell, the local reaction-transport competition index is calculated. The local Damcole number is calculated based on the local monitoring state vector of the grid cell, and the local Damcole number is mapped to a local near-critical weight index according to a preset near-critical weight function. The local non-exchangeable proxy index, the local reaction-transport competition index, and the local near-critical weight index are weighted and combined according to preset weight coefficients to generate the local splitting distortion risk index.

3. The combustion reactive flow operator splitting and switching method based on splitting distortion risk according to claim 2, characterized in that, The local non-commutative proxy index characterizes the upper bound of the truncation error caused by the non-commutativity of chemical reaction operators and transport operators in a local region. The local reaction-transport competition index characterizes the relative dominance of chemical reaction rate and matter-energy transport rate. The local near-critical weight index characterizes the sensitivity of the current grid cell to the boundary of ignition mode transition, flameout mode transition, or combustion mode transition.

4. The combustion reactive flow operator splitting and switching method based on splitting distortion risk according to claim 1, characterized in that, The local splitting distortion risk index of each grid cell is compared with a preset risk threshold, and high-risk grid cells are identified from each grid cell based on the comparison results, including: A dual-threshold hysteresis determination mechanism is used to compare the local splitting distortion risk index with a preset risk threshold. When the local splitting distortion risk index of a certain grid cell exceeds the preset upper threshold, the grid cell is marked as high-risk. When the local splitting distortion risk index of a grid cell that has been marked as high-risk is lower than the preset lower threshold, the high-risk label of the grid cell is removed. The lower threshold is less than the upper threshold. Perform spatial connectivity clustering on all grid cells in a high-risk state at the current moment, and merge spatially adjacent high-risk grid cells into the same high-risk connectivity region; A preset number of grid cells are extended outward from each of the high-risk connected regions as a buffer layer, and the grid cells in the buffer layer are included in the corresponding high-risk connected regions.

5. The combustion reactive flow operator splitting and switching method based on splitting distortion risk according to claim 1, characterized in that, The linkage adjustment integral control parameters include at least one of the following: Increase the maximum allowed number of iterations for chemical reaction sub-cycles within the high-risk connected regions; Tighten the local error tolerance coefficient of the chemical reaction solver in the high-risk connected region.

6. The combustion reactive flow operator splitting and switching method based on splitting distortion risk according to claim 5, characterized in that, At the boundary interface between the high-risk connected region and its adjacent grid cells, spatial weighted interpolation is performed on the integral control parameters to ensure a continuous transition of the integral control parameters when crossing the boundary interface.

7. The combustion reactive flow operator splitting and switching method based on splitting distortion risk according to claim 1, characterized in that, The steady-state preservation operator splitting scheme is selected from one of the following: the balanced operator splitting scheme, the simplified balanced operator splitting scheme, or the well-balanced operator splitting scheme. The conventional operator splitting scheme is selected from either the standard Lie-Trotter splitting scheme or the Strang splitting scheme.

8. The combustion reactive flow operator splitting and switching method based on splitting distortion risk according to claim 1, characterized in that, Also includes: After each time step is completed, state synchronization processing is performed on the boundary interface between the high-risk connected region and its adjacent grid cells, and conservation quantity correction updates are performed on the global computational domain to ensure the conservation of mass, momentum and energy at the cross-region interface.

9. A combustion reactive flow operator splitting and switching system based on splitting distortion risk, characterized in that, include: The state monitoring module is used to extract local monitoring state vectors that characterize the combustion state of each grid cell in the current computational domain during the time progression of the numerical simulation of combustion reaction flow. The risk assessment module is used to construct a local splitting distortion risk index for each grid cell based on the corresponding local monitoring state vector. The local splitting distortion risk index is a comprehensive index constructed based at least on the local non-exchange surrogate index, the local reaction-transport competition index, and the local near-critical weight index, which is used to quantify the risk of combustion mode prediction deviation generated by the conventional operator splitting scheme at the grid cell. The region identification module is used to compare the local splitting distortion risk index of each grid cell with a preset risk threshold, identify high-risk grid cells from each grid cell based on the comparison results, and cluster the high-risk grid cells into high-risk connected regions based on spatial adjacency relationships. The split control module is used to trigger a steady-state operator splitting scheme for time advancement for grid cells within the high-risk connected region and adjust the integral control parameters accordingly; for grid cells outside the high-risk connected region, it maintains the conventional operator splitting scheme for time advancement.

10. The combustion reactive flow operator splitting and switching system based on splitting distortion risk according to claim 9, characterized in that, Also includes: The memory is used to store a preset risk threshold configuration table corresponding to the local splitting distortion risk index; The boundary processing and update module is used to perform state synchronization processing on the boundary interface between the high-risk connected region and its adjacent grid cells after each time step is completed, and to perform conservation quantity correction update on the global computation domain to ensure the conservation of mass, momentum and energy of the cross-region interface.

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