CN112489734A - Method for simplifying combustion reaction mechanism model of internal combustion engine for replacing fuel dimethyl ether - Google Patents
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- LCGLNKUTAGEVQW-UHFFFAOYSA-N Dimethyl ether Chemical compound COC LCGLNKUTAGEVQW-UHFFFAOYSA-N 0.000 title claims abstract description 120
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- 239000004215 Carbon black (E152) Substances 0.000 description 1
- IMNFDUFMRHMDMM-UHFFFAOYSA-N N-Heptane Chemical class CCCCCCC IMNFDUFMRHMDMM-UHFFFAOYSA-N 0.000 description 1
- OMOVVBIIQSXZSZ-UHFFFAOYSA-N [6-(4-acetyloxy-5,9a-dimethyl-2,7-dioxo-4,5a,6,9-tetrahydro-3h-pyrano[3,4-b]oxepin-5-yl)-5-formyloxy-3-(furan-3-yl)-3a-methyl-7-methylidene-1a,2,3,4,5,6-hexahydroindeno[1,7a-b]oxiren-4-yl] 2-hydroxy-3-methylpentanoate Chemical compound CC12C(OC(=O)C(O)C(C)CC)C(OC=O)C(C3(C)C(CC(=O)OC4(C)COC(=O)CC43)OC(C)=O)C(=C)C32OC3CC1C=1C=COC=1 OMOVVBIIQSXZSZ-UHFFFAOYSA-N 0.000 description 1
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Abstract
The invention discloses a method for simplifying a combustion reaction mechanism model of dimethyl ether as an internal combustion engine alternative fuel, in particular to a method for simplifying a chemical reaction mechanism model by adopting a direct relation graph method, a sensitivity analysis method, an isomerous method, a computational singularity perturbation method and a diffusion species binding method. The method can be directly used for numerical simulation of the combustion flow field of the internal combustion engine for replacing fuel dimethyl ether, and provides effective technical support for numerical analysis of the internal combustion engine.
Description
Technical Field
The invention belongs to the technical field of computer simulation of combustion process of an internal combustion engine. To a simplified method of modeling combustion reaction mechanisms. And more particularly to a simplified method of a combustion reaction mechanism model of dimethyl ether (PODE) as an alternative fuel of an internal combustion engine.
Background
At present, two main ways are available for determining the emission and combustion efficiency of an internal combustion engine, one way is to measure the emission and performance of the internal combustion engine through an internal combustion engine test bench, the method has reliable results, and has the advantage of great guiding significance for high precision requirement, but the method has high cost and much time consumption, and is not suitable for being used in the whole development process of the internal combustion engine. The other method is to carry out numerical simulation on the working process of the internal combustion engine and study the working process of the internal combustion engine through computer three-dimensional simulation, and the method has the advantages of obviously shortening the product development period, reducing the number of times of real machine tests, reducing the product development cost and the like, and is an important research method. However, the numerical simulation of the combustion process involving multi-component and large number of elementary reactions has the problem of low calculation efficiency, and the extremely simplified one-step or two-step empirical combustion model cannot ensure the calculation accuracy due to insufficient description of the combustion process. The simplification of the combustion mechanism of hydrocarbon fuels has therefore become an important research direction in the field of combustion.
At the present stage, there are two main categories of combustion mechanism simplification: the first method is to reduce the number of elementary reactions, and the second method is to reduce the components in the reaction kinetic model, such as direct relationship graph method, and sensitivity analysis method assisted by direct relationship graph. Under the condition that the reaction kinetic model is large, the two methods are generally matched with each other, namely, components are firstly screened for simplification in the first stage, and the components in the reaction kinetic model are reduced in the second stage, so that the aim of simplification is finally achieved, and references can be made: a directed relationship graph method for mechanism reduction; stands for mechanism reduction for large hydrocarbons, n-heptanes.
Although the above-mentioned method for simplifying the combustion mechanism of dimethyl ether (PODE) can greatly reduce the mechanism of combustion reaction, the result obtained by the simplification is still insufficient for numerical calculation, and the simplified mechanism obtained by the above-mentioned method is not ideal for the applicability to the combustion situation in particular in engines, and is inferior in the case of the application condition of the mechanism of large component in particular. This condition can seriously affect the representation of important elementary reactions and main reaction paths in the fuel combustion process, and the simplification amplitude is large, and the uncertainty of the mechanism is high, so the simplified mechanism obtained by the simplification of the method cannot achieve the best effect of the reaction.
Disclosure of Invention
The invention aims to solve the problems and provides a simplified method for a combustion reaction mechanism model of dimethyl ether (PODE) as an alternative fuel of an internal combustion engine.
The method provided by the invention overcomes the problem of low calculation efficiency in the numerical simulation of the combustion process of the internal combustion engine in the prior art, overcomes the defects of the problem, reduces the number of components and elementary reactions on the basis of ensuring the calculation accuracy, improves the numerical calculation efficiency of the working process of the internal combustion engine, and has important significance for shortening the product development cycle of the internal combustion engine and reducing the development cost.
In order to achieve the purpose, the invention provides the following technical scheme:
a simplified method for an internal combustion engine to replace a fuel dimethyl ether combustion reaction mechanism model comprises the following steps:
the method comprises the following steps: determining acceptable error, setting threshold value, adding dimethyl ether and O2And N2Setting as a starting material; taking the equivalent ratio Phi to be 0.5-1.5, the temperature to be 700-1600K, and the pressure to be 1-50 atm. In the reaction, the contribution ratio of each component was compared. Contribution rate r of component B to component AABCan be expressed as:
kfi＝[AiTniexp(-Ei/RT)]Fi
wherein the indices i and j denote the ith base reaction and the jth species, V, respectivelyA,iIs the stoichiometric coefficient of A, ωiTo the production rate, kfiAnd kbiReaction rates, C, in forward and reverse directions, respectivelyjIs molar concentration, v'ij，v”ijStoichiometric coefficients of the respective forward and reverse reactions, AiAs a frequency factor, T is the temperature, Ei is the activation energy F of the chemical reactioniIs the correction coefficient, δBiThe values are as follows:
comparing the coupling relationship, the coupling relationship with small influence is eliminated. And judging the coupling relation between other intermediate products and the starting materials through the starting materials, and finally removing non-coupling components and obtaining a dimethyl ether combustion primary skeleton mechanism model.
Step two: and simplifying by using a sensitivity analysis method under the conditions that the equivalence ratio Phi is 0.5-1.5, the temperature is 700-1600K, and the pressure is 1-50 atm by using a primary framework mechanism model of the dimethyl ether obtained in the last step. The absolute and relative sensitivities of the changes in the concentration of the species participating in the reaction, which are influenced by the rate constant of the reaction, can be defined as:
from the formula, it can be seen that if Ei,rOr
The larger the concentration of the ith substance, the more the concentration of the ith substance is affected by the r-th reaction. Therefore, if Ei,rOr
Smaller, it means that the r-th reaction is not an important reaction for the i-th substance and can be eliminated from the reaction system. Obtaining a two-stage framework mechanism model for dimethyl ether combustion
Step three: according to the secondary framework mechanism model obtained in the step two, the equivalence ratio Phi is 0.5-1.5, the temperature is 700-1600K, and the pressure is 1-50 atm. And introducing Chemkin software, and simplifying by adopting an isomerization method to obtain a three-level framework mechanism model for dimethyl ether combustion.
Step four, the concrete content and steps are as follows:
the first step is that the three-level framework mechanism model obtained in the third step is under the conditions that the initial temperature is 700-1600K, the pressure is 1-50 atm, and the equivalence ratio is 0.5-1.5. Reading the stoichiometric coefficient and the arrhenius coefficient of the simplified mechanism elementary reaction in Chemkin, generating an Excel document, and saving the Excel document into a folder where a simplified program is located so as to be read. And then, calculating by adopting a simplified mechanism in Chemkin, and operating a Get Solution command to process a calculation result after the calculation is finished to obtain time, temperature and component concentration parameters in the reaction process, storing the parameters as a ckcsv table data file and also storing the parameters in a folder where a simplified program is located.
The second step is that: reading an Excel document containing detailed mechanism elementary reaction stoichiometric coefficients and arrhenius coefficients in matlab, generating a corresponding stoichiometric coefficient matrix and a corresponding reaction rate vector, and obtaining an expression of a reaction system component vector y and a component reaction rate vector g, thereby obtaining a Jacobian matrix.
The third step: reading the ckcsv file containing the component concentration, bringing the component concentration of the interested time point into the Jacobian matrix, solving the eigenvalue and the eigenvector of the Jacobian matrix at the moment, judging the number M of the rapid reaction modes at the moment according to the eigenvalue, and considering the eigenvector as a basis vector.
The fourth step: and correcting the trial basis vectors by using a two-step correction method, and greatly improving the diagonalization degree of the Jacobian matrix by correcting the trial basis vectors so as to realize the separation of the fast and slow modes.
The fifth step: and obtaining a fast space mapping matrix according to the corrected base vector and determining quasi-steady-state components, obtaining corresponding fast reactions according to the identified quasi-steady-state components, and removing the quasi-steady-state components and the fast reactions from the whole reaction system so as to obtain a four-level framework mechanism model of dimethyl ether combustion.
Step five: according to the four-level framework mechanism model of dimethyl ether combustion obtained in the fourth step, under the conditions that the initial temperature is 700-1600K, the pressure is 1-50 atm and the equivalence ratio is 0.5-1.5, a diffusion substance binding method is used for simplification, under the condition of particle binding, the calculation of diffusion terms is subjected to secondary acceleration, in various framework mechanisms, the diffusion model needs less diffusion species in an accurate description mode, and in a smaller dimethyl ether (PODE) mechanism, less than 10 diffusion species are needed. The CHEMIKIN software finds that the final simplified reaction mechanism is about one tenth of the detailed mechanism, and the final dimethyl ether combustion simplified mechanism model obtained after simplification is 18 components and 116 reaction formulas.
Step six, the concrete content and steps are as follows:
the first step is as follows: the simplified mechanism model file of dimethyl ether combustion was imported into the Chemkin reactor.
The second step is that: the conditions are that the temperature is 700-1600K, the pressure is 1-50 atm, the equivalence ratio is 0.5-1.5, and laminar flame and ignition delay execl table data are obtained by running in CHEMKIN.
The third step: the detailed mechanism file of dimethyl ether was imported into the CHEMKIN reaction software.
The fourth step: the conditions are that the temperature is 700-1600K, the pressure is 1-50 atm, the equivalence ratio is 0.5-1.5, and laminar flame and ignition delay execl table data are obtained by running in CHEMKIN.
Step seven: and drawing and comparing the data according to the laminar flame and ignition delay time data of the obtained final simplified reaction mechanism model and the detailed reaction mechanism model under the set conditions, checking whether the trends shown by the data graphs are the same and the error is within 10%, and if so, obtaining the simplified reaction mechanism model of the dimethyl ether. If not, go back to step one, adjust threshold, check step, repeat all steps again.
The invention has the following advantages and beneficial effects:
the invention simplifies the detailed mechanism model of dimethyl ether (PODE) by integrating a plurality of simplified methods, and can avoid the phenomenon that the components are inaccurately deleted in the simplified process of the traditional single method. The method is used for screening, screening and eliminating unimportant files of components in the dimethyl ether (PODE) fuel through a direct relational graph chemical reaction mechanism simplifying method, so that a model is simplified to the greatest extent, and a simplified framework mechanism is obtained. And then obtaining the global sensitivity analysis of the elements by a chemical mechanism simplification method of an allergic sensitivity analysis method, combining the global sensitivity analysis with an isomerous method, reducing the number of components in the reaction to the maximum, and simplifying by a singular perturbation calculation method and a diffusion species binding method so as to reduce the error between the result of the simplified model and the result of a detailed mechanism model to the greatest extent. The parameters related to the combustion properties represented by the numerical simulation results mainly include the ignition delay time and the change in data such as laminar flame. The sampling data in the detailed mechanism model provides a basis for the process, and the sampling data can be increased or decreased within the error allowable range to provide more appropriate data such as ignition delay time, laminar flame data and the like.
Drawings
FIG. 1 is a simplified process flow diagram of the present invention;
FIG. 2 is a graph of typical relationships between species in a Direct Relationship Graph (DRG);
FIG. 3 is a simplified flow diagram of a method of Computing Singular Perturbation (CSP);
FIG. 4 is an ignition delay map;
fig. 5 is a laminar flame diagram.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention is further described in detail with reference to the accompanying drawings and specific embodiments, and it should be understood that the specific embodiments described herein are only for explaining the present invention and are not intended to limit the present invention.
The invention discloses a simplified method of an alternative fuel dimethyl ether (PODE) combustion reaction mechanism model of an internal combustion engine, which comprises the following steps:
the method comprises the following steps: determining a well-acceptable error, setting a threshold, and converting PODE3、O2And N2Setting as a starting material; taking the equivalent ratio Phi to be 0.5-1.5, the temperature to be 700-1600K, and the pressure to be 1-50 atm. The degree of coupling between the two components was determined by Direct Relationship Graph (DRG).
In the reaction, substance B has a direct influence on the formation or consumption of substance A. The contribution rate r of component B to the generation of component AABCan be expressed as:
kfi＝[AiTniexp(-Ei/RT)]Fi
wherein the indices i and j denote the ith base reaction and the jth species, V, respectivelyA,iIs the stoichiometric coefficient of A, ωiTo the production rate, kfiAnd kbiReaction rates, C, in forward and reverse directions, respectivelyjIs molar concentration, v'ij，v”ijStoichiometric coefficients of the respective forward and reverse reactions, AiAs a frequency factor, T is the temperature, Ei is the activation energy F of the chemical reactioniIs the correction coefficient, δBiThe values are as follows:
the coupling relationship is eliminated with less influence compared to the coupling relationship (as shown in fig. 2). And judging the coupling relation between other intermediate products and the starting materials through the starting materials, and finally removing non-coupling components and obtaining a dimethyl ether combustion primary skeleton mechanism model.
Step two: and simplifying by using a sensitivity analysis method under the conditions that the equivalence ratio Phi is 0.5-1.5, the temperature is 700-1600K, and the pressure is 1-50 atm by using a primary framework mechanism model of the dimethyl ether obtained in the last step. The absolute and relative sensitivities of the changes in the concentration of the species participating in the reaction, which are influenced by the rate constant of the reaction, can be defined as:
from the formula, it can be seen that if Ei,rOr
The larger the concentration of the ith substance, the more the concentration of the ith substance is affected by the r-th reaction. Therefore, if Ei,rOr
Smaller, it means that the r-th reaction is not an important reaction for the i-th substance and can be eliminated from the reaction system. Obtaining a two-stage framework mechanism model for dimethyl ether combustion
Step three: according to the secondary framework mechanism model obtained in the step two, the equivalence ratio Phi is 0.5-1.5, the temperature is 700-1600K, and the pressure is 1-50 atm. And introducing Chemkin software, and simplifying by adopting an isomerization method to obtain a three-level framework mechanism model for dimethyl ether combustion.
Step four, the concrete content and steps are as follows:
the first step is that the three-level framework mechanism model obtained in the third step is under the conditions that the initial temperature is 700-1600K, the pressure is 1-50 atm, and the equivalence ratio is 0.5-1.5. Reading the stoichiometric coefficient and the arrhenius coefficient of the simplified mechanism elementary reaction in Chemkin, generating an Excel document, and saving the Excel document into a folder where a simplified program is located so as to be read. And then, calculating by adopting a simplified mechanism in Chemkin, and operating a Get Solution command to process a calculation result after the calculation is finished to obtain time, temperature and component concentration parameters in the reaction process, storing the parameters as a ckcsv table data file and also storing the parameters in a folder where a simplified program is located.
The second step is that: reading an Excel document containing detailed mechanism elementary reaction stoichiometric coefficients and arrhenius coefficients in matlab, generating a corresponding stoichiometric coefficient matrix and a corresponding reaction rate vector, and obtaining an expression of a reaction system component vector y and a component reaction rate vector g, thereby obtaining a Jacobian matrix.
The third step: reading the ckcsv file containing the component concentration, bringing the component concentration of the interested time point into the Jacobian matrix, solving the eigenvalue and the eigenvector of the Jacobian matrix at the moment, judging the number M of the rapid reaction modes at the moment according to the eigenvalue, and considering the eigenvector as a basis vector.
The fourth step: and correcting the trial basis vectors by using a two-step correction method, and greatly improving the diagonalization degree of the Jacobian matrix by correcting the trial basis vectors so as to realize the separation of the fast and slow modes.
The fifth step: and (3) obtaining a fast space mapping matrix according to the corrected base vector, determining quasi-steady-state components, obtaining corresponding fast reactions according to the identified quasi-steady-state components, and removing the quasi-steady-state components and the fast reactions from the whole reaction system to obtain a four-level framework mechanism model of dimethyl ether combustion, wherein a simplified flow chart is shown in fig. 3.
Step five, the concrete content and steps are as follows:
the first step is as follows: according to the four-level framework mechanism model of dimethyl ether combustion obtained in the fourth step, a diffusion substance binding method is used for simplification under the conditions that the initial temperature is 700-1600K, the pressure is 1-50 atm and the equivalence ratio is 0.5-1.5.
The second step is that: in the case of particle binding, the calculation of the diffusion term is accelerated twice, and in many skeletal mechanisms, less than 10 diffusion species are required to accurately describe the diffusion model, and in smaller dimethyl ether (PODE) mechanisms, less than 10 diffusion species are required. Through CHEMIKIN software, we find that the final simplified reaction mechanism is about one tenth of the detailed mechanism, and the final dimethyl ether combustion simplified mechanism model obtained after simplification is 18 components and 116 reaction formulas.
Step six, the concrete content and steps are as follows:
the first step is as follows: the simplified mechanism model file of dimethyl ether combustion was imported into the Chemkin reactor.
The second step is that: the conditions are that the temperature is 700-1600K, the pressure is 1-50 atm, the equivalence ratio is 0.5-1.5, and laminar flame and ignition delay execl table data are obtained by running in CHEMKIN.
The third step: the detailed mechanism file of dimethyl ether was imported into the CHEMKIN reaction software.
The fourth step: the conditions are that the temperature is 700-1600K, the pressure is 1-50 atm, the equivalence ratio is 0.5-1.5, and laminar flame and ignition delay execl table data are obtained by running in CHEMKIN.
Step seven, the concrete content and steps are as follows:
the first step is as follows: according to the laminar flame and ignition delay time data of the obtained final simplified reaction mechanism model and the detailed reaction mechanism model of the dimethyl ether under the set conditions,
the second step is that: the data were plotted and compared, and it was checked whether the trends exhibited by the data plots were the same and the error was within 10%, and if so, a simplified reaction mechanism model of the obtained dimethyl ether was desirable. If not, go back to step one, adjust threshold, check step, repeat all steps again. Referring to the comparative figure, FIG. 4 is an ignition delay map, FIG. 5: laminar flame diagram.
Finally, the description is as follows: although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art will understand that various changes, modifications and substitutions can be made without departing from the spirit and scope of the invention as defined by the appended claims. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (7)
1. A simplified method for a combustion reaction mechanism model of dimethyl ether as an internal combustion engine alternative fuel is characterized by comprising the following steps:
the method comprises the following steps: according to a detailed reaction mechanism model of dimethyl ether, deleting non-important reactions in the detailed reaction mechanism model by adopting a direct relational graph method to obtain a primary framework mechanism model of dimethyl ether fuel reaction;
step two: simplifying the first-stage framework mechanism model obtained in the first step by adopting a sensitivity analysis method assisted by a direct relational graph, judging the sensitivity of the first-stage framework mechanism model, and deleting a reaction formula with poor sensitivity to obtain a second-stage framework mechanism model of the dimethyl ether;
step three: according to the second-level framework mechanism model obtained in the second step, further simplifying the second-level framework mechanism model by an isomerization method to obtain a third-level framework mechanism model of the dimethyl ether;
step four: according to the three-level framework mechanism model obtained in the step three, a singular perturbation method is calculated for further simplification, and a four-level framework mechanism model of the dimethyl ether is obtained;
step five: according to the four-level framework mechanism model obtained in the step four, further simplifying by a diffusion species binding method to obtain a final simplified reaction mechanism model of the dimethyl ether fuel;
step six: respectively introducing the final simplified reaction mechanism model of the obtained dimethyl ether fuel and the detailed reaction mechanism model of the dimethyl ether into a zero-dimensional homogeneous combustor in Chemkin software for simulation, setting conditions in the Chemkin software that the equivalence ratio Phi is 0.5-1.5, the temperature is 700-1600K, and the pressure is 1-50 atm, and respectively obtaining the laminar flame and ignition delay time data of the final simplified reaction mechanism model of the dimethyl ether and the detailed reaction mechanism model of the dimethyl ether under the set conditions;
step seven: and drawing and comparing the data according to the laminar flame and ignition delay time data of the obtained final simplified reaction mechanism model and the detailed reaction mechanism model under the set conditions, checking whether the trends presented by the data graphs are the same and the error is within 10%, if so, obtaining the simplified reaction mechanism model of the dimethyl ether, and returning to the step one, adjusting the threshold value, checking the step and repeating all the steps again.
2. The simplified method of an alternative fuel combustion reaction mechanism model for an internal combustion engine according to claim 1, wherein: the specific contents and steps of the direct relationship graph method in the step one are as follows:
determining acceptable error, setting threshold value, adding dimethyl ether and O2And N2Setting as a starting material; taking the equivalent ratio Phi of 0.5-1.5, the temperature of 700-1600K and the pressure of 1-50 atm, determining the coupling degree between the two components by a direct relational graph method, judging the coupling relation between the intermediate product and the starting material by the relation between the starting materials, and finally removing the non-coupling components to further obtain a primary framework mechanism model of the dimethyl ether.
3. The simplified method of an alternative fuel combustion reaction mechanism model for an internal combustion engine according to claim 1, wherein: the specific content and steps of the sensitivity analysis method assisted by the direct relational graph in the second step are as follows:
and (3) obtaining a primary framework mechanism model of the dimethyl ether by utilizing the first step, wherein the primary framework mechanism model of the dimethyl ether is simplified by utilizing a sensitivity analysis method under the conditions that the equivalence ratio Phi is 0.5-1.5, the temperature is 700-1600K, and the pressure is 1-50 atm, so that the reaction with poor sensitivity is removed, and the secondary framework mechanism model of the dimethyl ether is obtained.
4. The simplified method of an alternative fuel combustion reaction mechanism model for an internal combustion engine according to claim 1, wherein: the specific content and steps of the isomerization method in the third step are as follows:
and (3) obtaining a two-stage framework mechanism model of the dimethyl ether by utilizing the second step, setting conditions in Chemkin software that the equivalence ratio Phi is 0.5-1.5, the temperature is 700-1600K, the pressure is 1-50 atm, and simplifying by adopting an isomerization method so as to obtain the three-stage framework mechanism model of the dimethyl ether.
5. The simplified method of an alternative fuel combustion reaction mechanism model for an internal combustion engine according to claim 1, wherein: the specific content and steps of the singular perturbation calculation method in the fourth step are as follows:
utilizing the three-level framework mechanism model of the dimethyl ether obtained in the third step, wherein the initial temperature is 700-1600K, the pressure is 1-50 atm, and the equivalence ratio is 0.5-1.5; reading a stoichiometric coefficient and an arrhenius coefficient of the simplified mechanism elementary reaction in CHEMIKIN, generating an Excel document and storing the Excel document in a folder where a simplified program is located; and then combining with matlab to obtain a four-level framework mechanism model of the dimethyl ether fuel.
6. The simplified method of an alternative fuel combustion reaction mechanism model for an internal combustion engine according to claim 1, wherein: the concrete content and steps of the diffusion substance binding method in the fifth step are as follows:
and (3) obtaining a four-stage framework mechanism model of the dimethyl ether by utilizing the step four, and under the conditions that the temperature is 700-1600K, the pressure is 1-50 atm, and the equivalence ratio is 0.5-1.5, simplifying by using a diffusion substance binding method, eliminating unnecessary reactions, and obtaining a final simplified mechanism model of the dimethyl ether fuel, wherein the simplified mechanism model is 18 components and 116 reaction formulas.
7. The simplified method of an alternative fuel combustion reaction mechanism model for an internal combustion engine according to claim 1, wherein: the concrete content and steps of the sixth step are as follows:
the first step is as follows: importing a simplified mechanism model file of dimethyl ether combustion into a Chemkin reactor;
the second step is that: setting conditions: running in CHEMKIN at the temperature of 700-1600K and the pressure of 1-50 atm, wherein the equivalence ratio is 0.5-1.5 to obtain laminar flame and ignition delay execl table data;
the third step: importing a detailed mechanism file of dimethyl ether into reaction software of CHEMKIN;
the fourth step: setting conditions: the temperature is 700-1600K, the pressure is 1-50 atm, the equivalence ratio is 0.5-1.5, and laminar flame and ignition delay execl table data are obtained by running in CHEMKIN.
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| CN114067924A (en) * | 2021-11-23 | 2022-02-18 | 江苏科技大学 | Method for simplifying reaction mechanism model of dimethyl ether-polyformaldehyde dimethyl ether 3 as alternative fuel of internal combustion engine |
| CN115248978A (en) * | 2022-07-01 | 2022-10-28 | 北京理工大学 | Method for simplifying combustion dynamics mechanism of long-chain normal alcohol fuel |
| CN116798531A (en) * | 2023-06-29 | 2023-09-22 | 西南科技大学 | Fusion algorithm-based hydrocarbon fuel mechanism simplification method for supersonic combustion chamber |
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| CN116798531A (en) * | 2023-06-29 | 2023-09-22 | 西南科技大学 | Fusion algorithm-based hydrocarbon fuel mechanism simplification method for supersonic combustion chamber |
| CN116798531B (en) * | 2023-06-29 | 2024-03-22 | 西南科技大学 | Fusion algorithm-based hydrocarbon fuel mechanism simplification method for supersonic combustion chamber |
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