A method for predicting spray jet penetration distance for gas-liquid two-phase flexible fuel internal combustion engines

Abstract

A method for predicting the penetration distance of a spray jet for a gas-liquid two-phase flexible fuel internal combustion engine, the invention relates to the field of simulation calculation of the engine spray jet process. The method solves the problem that there is currently no calculation method suitable for the penetration distance of a flexible fuel spray jet for an internal combustion engine, and lacks theoretical analysis and performance optimization tools. The method includes obtaining the instantaneous injection velocity of the flexible fuel spray jet, as well as the turbulent viscosity and time length of the flexible fuel spray jet, and obtaining the vortex ring size and vortex ring mass in combination with the motion law of the vortex ring along the flow field; obtaining the momentum response time and effective injection velocity of the vortex ring; obtaining the effective injection velocity of the vortex ring in combination with the fuel density and the nozzle outlet area, using a variable time upper limit integral method to calculate the effective injection velocity of the flexible fuel instantaneous steady-state jet, and coupling it with a penetration distance analytical model to obtain the law of change of the flexible fuel spray jet penetration distance over time. It is applicable to the field of calculation methods for the penetration distance of flexible fuel spray jets for internal combustion engines.

Description

Technical Field

[0001] The invention relates to the technical field of simulation calculation of engine spray jet process. Background Art

[0002] With the increasingly stringent regulations on carbon dioxide emissions in recent years, various industries have proposed a series of dual-carbon strategic measures. As the main power unit for land and sea transportation, internal combustion engines bring convenience to human life while also emitting a large amount of carbon dioxide. Supplying low-carbon or zero-carbon fuels such as ammonia, hydrogen or natural gas to internal combustion engines is the current mainstream development trend for implementing the dual-carbon strategy, which can significantly reduce carbon emissions from the source. Moreover, these green fuels have a wide range of sources and mature production and synthesis technologies, which can ensure the long-term and stable development of internal combustion engines.

[0003] For flexible fuel internal combustion engines, a good spray jet mixing state is an important prerequisite for improving combustion quality and promoting engine performance. However, with the diversification of internal combustion engine fuel types, the spray jet development process in the cylinder has become more complicated, especially when traditional liquid fuels such as gasoline and diesel are expanded to emerging gas fuels such as hydrogen and natural gas, the physical and chemical properties of the fuel have changed greatly. For example, the development of gas fuel jets does not involve droplet atomization, fragmentation and evaporation processes, so it diffuses faster, has a larger cone angle, mixes faster with air, and the equivalence ratio quickly tends to be uniform. For renewable and biodegradable biodiesel, its viscosity and surface tension are usually large. Higher fuel viscosity will inhibit airflow disturbances on the spray surface and delay the breakup process of the spray, while higher surface tension coefficients will increase droplet cohesion, thereby significantly increasing the size of droplets, and the spray penetration will be faster due to momentum concentration. At the same time, the narrowing of the spray cone angle reduces the radial diffusion area, while the longer penetration distance expands the axial propagation area. In addition, due to the influence of the fuel viscosity, the radial velocity and fuel concentration distribution on the spray cross section have undergone tremendous changes. These factors combined make the spray mixing characteristics of high-viscosity fuels such as biodiesel extremely complex. As the most promising zero-carbon fuel at present, ammonia has completely different physical properties from diesel. For example, the kinematic viscosity and latent heat of vaporization of ammonia are both 5 times that of diesel, while its low calorific value and density are much smaller than diesel. Therefore, in order to maintain the high power input of ammonia fuel internal combustion engines, a larger aperture injector is required to provide a higher volume flow rate. However, large aperture injection is not conducive to the breakup and atomization of ammonia fuel droplets. The high viscosity leads to a shorter spray penetration distance. At the same time, the higher latent heat of vaporization will bring a strong cooling effect to the spray, which greatly weakens the mixing quality of ammonia spray. In summary, the spray jet development process brought about by different internal combustion engine fuels is also completely different. As an important spray characteristic parameter, the spray jet penetration distance characterizes the macroscopic distribution state of the spray jet and can be used to measure the mixing effect of fuel and gas in the internal combustion engine, so as to optimize and adjust the flexible fuel injection strategy, improve the subsequent combustion process and improve efficiency. However, there is currently no calculation method for the flexible fuel spray jet penetration distance of internal combustion engines, and there is a lack of effective theoretical analysis and performance optimization tools.

[0004] Therefore, based on the balance between the momentum change and resistance of the vortex ring, the present invention obtains the momentum response time and effective injection velocity of the vortex ring through the size change law of the vortex ring moving along the flow field, and obtains the effective injection velocity of the spray jet according to the instantaneous steady-state jet hypothesis. Then, the effective injection velocity is coupled with the penetration distance analytical model, and a spray jet penetration distance prediction method for gas-liquid two-phase flexible fuel internal combustion engines is proposed. Summary of the invention

[0005] The present invention aims at the problem that there is no calculation method suitable for the penetration distance of flexible fuel spray jet of internal combustion engine in the prior art, and there is a lack of effective theoretical analysis and performance optimization tools. To solve the above technical problems, the present invention is implemented by the following technical solutions:

[0006] The present invention proposes a method for predicting the spray jet penetration distance for a gas-liquid two-phase flexible fuel internal combustion engine. The method comprises the following steps:

[0007] Step 1: According to the fuel injection pressure P f , ambient gas pressure P g , fuel density ρ f and speed factor C v , obtain the instantaneous injection velocity U of the flexible fuel spray jet inj ;

[0008] Step 2: Based on the instantaneous injection velocity U obtained in step 1 inj and effective nozzle diameter d eq , to obtain the turbulent viscosity ν of the flexible fuel spray jet t and the time length τ t , and combined with the motion law of the vortex ring along the flow field, the vortex ring size D and the vortex ring mass m are obtained;

[0009] Step 3: Based on the turbulent viscosity ν obtained in step 2 t , time length τ t , vortex ring size D and vortex ring mass m, obtain the momentum response time τ of the vortex ring v and effective injection velocity υ;

[0010] Step 4: Based on the vortex ring effective injection velocity υ obtained in step 3, combined with the fuel density and the nozzle outlet area A noz The effective injection velocity U of the instantaneous steady-state jet of the flexible fuel is calculated by using the variable time upper limit integral method. eff (t);

[0011] Step 5: Set the effective injection velocity U at any instantaneous flexible fuel spray jet tip to eff (t) is coupled with the penetration distance analytical model to obtain the flexible fuel spray jet penetration distance S tip (t) Change pattern over time.

[0012] Further, a preferred embodiment is provided, in step 2, the effective nozzle diameter d eq Calculated by the following formula:

[0013]

[0014] Among them, d n is the nozzle diameter, ρg is the ambient gas density.

[0015] Further, a preferred embodiment is provided, in step 2, the turbulent viscosity ν t and the time length τ t Calculated by the following formula:

[0016]

[0017]

[0018] Among them, τ t =τ elapsed +τ0,τ elapsed is the migration time of the spray jet in the flow field, τ0 is the initial time, C t is the turbulence coefficient.

[0019] Further, a preferred embodiment is provided, in step 2, the vortex ring size D and the vortex ring mass m are calculated by the following formula:

[0020]

[0021]

[0022] in, is the fluid injection rate.

[0023] Further, a preferred embodiment is provided, in which the momentum response time τ of the vortex ring in step 3 is v And the effective injection velocity υ is obtained by the following formula:

[0024]

[0025]

[0026] Where μ is the dynamic viscosity of the ambient gas.

[0027] Furthermore, a preferred embodiment is provided, in which the effective injection velocity U of the instantaneous steady-state jet of the flexible fuel is calculated by using the variable time upper limit integral method. eff The method of (t) is:

[0028]

[0029] Among them, U inj (t k ) is t k The injection velocity at the injection moment, τ k is the momentum response time.

[0030] Further, a preferred embodiment is provided, in step 5, the flexible fuel spray jet penetration distance S tip The change of (t) over time is calculated by the following formula:

[0031]

[0032] Among them, C d is the nozzle diameter contraction coefficient, β is the spray section velocity and volume fraction distribution factor, t j It is the duration of fuel injection.

[0033] Solution 2: A computer device includes a memory and a processor, wherein the memory stores a computer program. When the processor runs the computer program stored in the memory, the processor executes any one of the methods described in Solution 1.

[0034] Solution three: a computer-readable storage medium storing a computer program, wherein the computer program, when executed by a processor, implements the steps of the method described in any one of Solution one.

[0035] The present invention is beneficial in that:

[0036] The present invention grasps the common law of gas-liquid two-phase jet mechanism based on the change of vortex ring momentum and resistance balance, can be applied to different internal combustion engine fuels, and broadens the scope of application.

[0037] Secondly, the present invention obtains the momentum response time and effective injection velocity of the vortex ring through the size change law of the vortex ring moving along the flow field, thereby improving the calculation accuracy and speed of the spray jet penetration distance under variable injection conditions; then, the present invention calculates the effective injection velocity of the spray jet by using a variable time upper limit integral through the transformation of an arbitrary variable injection rate curve and an instantaneous steady-state jet, so that the influence of the instantaneous injection velocity change is timely applied to the development process of the spray jet penetration distance, thereby improving the calculation accuracy.

[0038] Finally, the present invention couples the effective injection velocity of the spray jet with the analytical model of the penetration distance, and uses an analytical method to calculate the spray jet penetration distance of different fuels under any variable injection strategy, which significantly improves the calculation speed and provides a faster, more accurate and efficient numerical research method for the analysis of the spray jet development process of flexible fuel internal combustion engines.

[0039] The present invention is also applicable to the field of calculation methods for flexible fuel spray jet penetration distance of internal combustion engines. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a flow chart of a method for predicting spray jet penetration distance for a gas-liquid two-phase flexible fuel internal combustion engine as described in Implementation Example 1.

[0041] Figure 2 An arbitrary variable injection curve and its instantaneous steady-state jet conversion diagram of a spray jet penetration distance prediction method for a gas-liquid two-phase flexible fuel internal combustion engine as described in Implementation Method 1.

[0042] Figure 3 It is a schematic diagram of injection parameters under the variable injection strategy of ammonia fuel described in the eleventh embodiment.

[0043] Figure 4 It is a schematic diagram comparing the calculation results of the variable injection rate curve of ammonia fuel and the spray penetration distance described in the eleventh embodiment with the experimental data. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solutions and advantages of the implementation methods of the present application clearer, the technical solutions in the implementation methods of the present application will be clearly and completely described below in conjunction with the drawings in the implementation methods of the present application. Obviously, the described implementation methods are only part of the implementation methods of the present application, not all of the implementation methods.

[0045] Embodiment 1: This embodiment provides a method for predicting the spray jet penetration distance for a gas-liquid two-phase flexible fuel internal combustion engine. The method for predicting the spray jet penetration distance comprises the following steps:

[0046] Step 1: According to the fuel injection pressure P f , ambient gas pressure P g , fuel density ρ f and speed factor C v , obtain the instantaneous injection velocity U of the flexible fuel spray jet inj ;

[0047] Step 2: Based on the instantaneous injection velocity U obtained in step 1 inj and effective nozzle diameter d eq , to obtain the turbulent viscosity ν of the flexible fuel spray jet t and the time length τ t , and combined with the motion law of the vortex ring along the flow field, the vortex ring size D and the vortex ring mass m are obtained;

[0048] Step 3: Based on the turbulent viscosity ν obtained in step 2 t , time length τ t , vortex ring size D and vortex ring mass m, obtain the momentum response time τ of the vortex ring v and effective injection velocity υ;

[0049] Step 4: Based on the vortex ring effective injection velocity υ obtained in step 3, combined with the fuel density and the nozzle outlet area A noz The effective injection velocity U of the instantaneous steady-state jet of the flexible fuel is calculated by using the variable time upper limit integral method.eff (t);

[0050] Step 5: Set the effective injection velocity U at any instantaneous flexible fuel spray jet tip to eff (t) is coupled with the penetration distance analytical model to obtain the flexible fuel spray jet penetration distance S tip (t) Change pattern over time.

[0051] See also Figures 1 to 4 The instantaneous injection velocity U of the flexible fuel spray jet in step 1 of this embodiment is described as follows: inj It is calculated by the following formula, that is,

[0052]

[0053] This embodiment obtains the size variation law of the vortex ring along the flow field through fuel injection parameters and ambient air conditions. Then, the momentum response time and effective injection velocity of the vortex ring are obtained based on the vortex ring momentum change and resistance balance. Then, based on the instantaneous steady-state jet assumption, any variable injection curve is equivalent to a steady-state spray jet at any instant, and the effective injection velocity of the spray jet is calculated. Finally, the effective injection velocity of the flexible fuel spray jet under any instantaneous variable injection strategy is coupled with the penetration distance analytical model to obtain the spray jet penetration distance analytical formula for the gas-liquid two-phase flexible fuel internal combustion engine.

[0054] Embodiment 2: This embodiment further defines the method for predicting the spray jet penetration distance for a gas-liquid two-phase flexible fuel internal combustion engine described in Embodiment 1. In step 2, the effective nozzle diameter d eq Calculated by the following formula:

[0055]

[0056] Among them, d n is the nozzle diameter, ρ g is the ambient gas density.

[0057] The effective nozzle hole diameter d in this embodiment eq , through the nozzle diameter d n Calculated.

[0058] Embodiment 3: This embodiment further defines the method for predicting the spray jet penetration distance for a gas-liquid two-phase flexible fuel internal combustion engine described in Embodiment 1. The turbulent viscosity ν in step 2 is t and the time length τ t Calculated by the following formula:

[0059]

[0060]

[0061] Among them, τ t =τ elapsed +τ0,τ elapsed is the migration time of the spray jet in the flow field, τ0 is the initial time, C t is the turbulence coefficient.

[0062] Embodiment 4: This embodiment further defines the method for predicting the spray jet penetration distance for a gas-liquid two-phase flexible fuel internal combustion engine described in Embodiment 1. In step 2, the vortex ring size D and the vortex ring mass m are calculated by the following formula:

[0063]

[0064]

[0065] in, is the fluid injection rate.

[0066] Embodiment 5: This embodiment further defines the method for predicting the spray jet penetration distance for a gas-liquid two-phase flexible fuel internal combustion engine described in Embodiment 1. The momentum response time τ of the vortex ring in step 3 is v And the effective injection velocity υ is obtained by the following formula:

[0067]

[0068]

[0069] Where μ is the dynamic viscosity of the ambient gas.

[0070] Embodiment 6: This embodiment further limits the spray jet penetration distance prediction method for a gas-liquid two-phase flexible fuel internal combustion engine described in Embodiment 1, and uses a variable time upper limit integral method to calculate the effective injection velocity U of the instantaneous steady-state jet of the flexible fuel. eff The method of (t) is:

[0071]

[0072] Among them, U inj (t k ) is t k The injection velocity at the injection moment, τ k is the momentum response time.

[0073] Embodiment 7: This embodiment further defines the spray jet penetration distance prediction method for a gas-liquid two-phase flexible fuel internal combustion engine described in Embodiment 1. In step 5, the flexible fuel spray jet penetration distance S tipThe change of (t) over time is calculated by the following formula:

[0074]

[0075] Among them, C d is the nozzle diameter contraction coefficient, β is the spray section velocity and volume fraction distribution factor, t j It is the duration of fuel injection.

[0076] Embodiment 8: A computer device includes a memory and a processor, wherein the memory stores a computer program, and when the processor runs the computer program stored in the memory, the processor executes the method described in any one of embodiments 1 to 7.

[0077] Embodiment 9: A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method described in any one of embodiments 1 to 7 are implemented.

[0078] Embodiment 10: This embodiment provides an example, which is used to explain the above embodiments 1 to 9. The specific example is as follows:

[0079] See also Figure 1 and Figure 4 This embodiment is described. Its purpose is to provide a method for predicting the spray jet penetration distance of a gas-liquid two-phase flexible fuel internal combustion engine, to achieve rapid and robust prediction of the spray jet penetration distances of different fuels under variable injection rate conditions, and to provide theoretical analysis and engineering evaluation tools for adjusting the injection strategy and optimizing the mixing process of the internal combustion engine.

[0080] In order to fill the gap in the research field of spray jet penetration distance of flexible fuel internal combustion engines, this embodiment first obtains the size change law of the vortex ring moving along the flow field through fuel injection parameters and ambient air conditions. Then, the momentum response time and effective injection velocity of the vortex ring are obtained based on the vortex ring momentum change and resistance balance. Next, based on the instantaneous steady-state jet assumption, any variable injection curve is equivalent to a steady-state spray jet at any instant, and the effective injection velocity of the spray jet is calculated. Finally, the effective injection velocity of the flexible fuel spray jet under any instantaneous variable injection strategy is coupled with the penetration distance analytical model to obtain the analytical formula of the spray jet penetration distance for gas-liquid two-phase flexible fuel internal combustion engines.

[0081] This implementation is based on the balance between the change in momentum of the vortex ring and the resistance. The momentum response time and effective injection velocity of the vortex ring are obtained through the law of size change of the vortex ring along the flow field. The effective injection velocity of the spray jet is obtained based on the instantaneous steady-state jet hypothesis. Then, the effective injection velocity is coupled with the penetration distance analytical model to propose a method for predicting the spray jet penetration distance for a gas-liquid two-phase flexible fuel internal combustion engine. This method has fast calculation speed and high calculation accuracy. It can be applied to different gas-liquid two-phase internal combustion engine fuels and any variable injection strategies, including single injection and multiple injections, etc., providing a simpler and more efficient unified numerical research method for the analysis of the development process of the spray jet of a flexible fuel internal combustion engine.

[0082] The purpose of this embodiment is achieved through the following technical solutions:

[0083] Step 1: According to the nozzle diameter d n , fuel density ρ f and ambient gas density ρ g , calculate the effective nozzle diameter d eq :

[0084]

[0085] Step 2: According to the turbulence coefficient C t , injection speed U inj and effective nozzle diameter d eq , the turbulent viscosity ν is calculated t :

[0086]

[0087] Step 3: According to the nozzle diameter d n , turbulent viscosity ν t and the migration time τ of the spray jet in the flow field elapsed , calculate the initial time τ0 and time length τ t : τ t =τ elapsed +τ0;

[0088] Step 4: According to the turbulent viscosity ν t and the time length τ t , the vortex ring size D is calculated:

[0089] Step 5: According to the fluid injection rate The mass m of the vortex ring per unit time Δt is calculated as:

[0090] Step 6: Calculate the vortex ring momentum response time τ based on the vortex ring size D, vortex ring mass m and ambient gas dynamic viscosity μ v:

[0091] Step 7: According to the injection speed U inj and vortex ring momentum response time τ v , the effective injection velocity υ of the vortex ring is calculated:

[0092]

[0093] Step 8: Adoption Figure 2 The method exemplified here converts any variable injection curve into an instantaneous steady-state jet according to t k The injection speed U at the injection moment inj (t k ) and momentum response time τ k , fuel density ρ f And the nozzle outlet area A noz , the effective injection velocity U of the instantaneous steady-state spray jet is calculated by using the variable time t upper limit integration method eff (t);

[0094]

[0095] Step 9: According to the fuel density ρ f 、Ambient gas density ρ g And the empirical coefficient c, the spray cone angle θ is calculated,

[0096]

[0097] Step 10: According to the nozzle diameter contraction coefficient C d , spray cross-sectional velocity and volume fraction distribution factor β, effective injection velocity U of the spray jet eff (t), effective nozzle diameter d eq , spray cone angle θ and injection duration t j , the spray jet penetration distance S is calculated tip (t) Changes over time:

[0098]

[0099] Figure 1Any process or method description in the flowchart described in or otherwise described herein can be understood as representing a module, fragment or portion of a code including one or more executable instructions for implementing the steps of a custom logic function or process, and the scope of the preferred embodiment of the present invention includes other implementations, in which the functions may be performed in a substantially simultaneous manner or in a reverse order according to the functions involved, which should be understood by a person skilled in the art of the present invention. The logic and / or steps represented in the flowchart or otherwise described herein illustrate the possible implementation architecture, functions and operations of the apparatus and methods according to various embodiments of the present disclosure. In this regard, each box in the flowchart or block diagram can represent a module, a program segment, or a part of a code, and the above-mentioned module, program segment, or a part of a code contains one or more executable instructions for implementing the specified logic function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in reverse order, depending on the functions involved. It is also noted that each block in the block diagram or flowchart, and combinations of blocks in the block diagram or flowchart, may be implemented by a dedicated hardware-based system that performs the specified functions or operations, or may be implemented by a combination of dedicated hardware and computer instructions. For example, what may be considered as an ordered list of executable instructions for implementing a logical function may be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other system that can fetch instructions from and execute instructions in an instruction execution system, apparatus, or device).

[0100] For the purposes of the present specification, "computer-readable medium" may be any device that can contain, store, communicate, propagate or transmit a program for use with an instruction execution system, device or equipment or in conjunction with these instruction execution systems, devices or equipment. More specific examples of computer-readable media (non-exhaustive list) include the following: an electrical connection with one or N wirings (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and editable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program may be printed, because the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting or processing in other suitable ways as necessary, and then stored in a computer memory. It should be understood that the various parts of the present invention may be implemented in hardware, software, firmware or a combination thereof. In the above embodiments, the N steps or methods may be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one of the following technologies known in the art or a combination thereof: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0101] Those skilled in the art will appreciate that the above are only preferred embodiments of the present invention, and the various embodiments of the present disclosure and / or the features described in the claims may be combined or combined in various ways, even if such combinations or combinations are not explicitly described in the present disclosure. It is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art may still modify the technical solutions described in the aforementioned embodiments, or perform equivalent substitutions on some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

[0102] Although preferred embodiments of the present invention have been described, additional changes and modifications may be made to these embodiments by those skilled in the art once the basic inventive concepts are known. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention. Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for predicting the spray jet penetration distance of a gas-liquid two-phase flexible fuel internal combustion engine, characterized in that: The spray jet penetration distance prediction method comprises the following steps: Step 1: According to the fuel injection pressure , Ambient gas pressure , fuel density and speed factor , to obtain the instantaneous injection velocity of the flexible fuel spray jet ; Step 2: Based on the instantaneous injection velocity obtained in step 1 and effective nozzle diameter , to obtain the turbulent viscosity of the flexible fuel spray jet and duration , and combined with the motion law of the vortex ring along the flow field, the vortex ring size is obtained and vortex ring mass ; Step 3: Turbulent viscosity based on step 2 , duration , vortex ring size and vortex ring mass , get the momentum response time of the vortex ring and effective injection velocity ; Step 4: According to the effective injection velocity of the vortex ring obtained in step 3 Combined fuel density and nozzle outlet area The effective injection velocity of the instantaneous steady-state flexible fuel jet is calculated using the variable time upper limit integral method. ; Step 5: Set the effective injection velocity at any instantaneous flexible fuel spray jet tip to The flexible fuel spray jet penetration distance is obtained by coupling with the penetration distance analytical model. Patterns of change over time; Effective nozzle diameter in step 2 Calculated by the following formula: in, is the nozzle diameter, is the ambient gas density; Turbulent viscosity in step 2 and duration Calculated by the following formula: in, , is the migration time of the spray jet in the flow field, is the initial time, is the turbulence coefficient; Vortex ring size in step 2 and vortex ring mass Calculated by the following formula: in, is the fluid injection rate; Momentum response time of the vortex ring in step 3 and effective injection velocity Obtained by the following formula: in, is the dynamic viscosity of the ambient gas; The effective injection velocity of the instantaneous steady-state flexible fuel jet is calculated using the variable time upper limit integral method. The method is: in, for The injection speed at the injection moment, is the momentum response time.

2. The method for predicting the spray jet penetration distance for a gas-liquid two-phase flexible fuel internal combustion engine according to claim 1, characterized in that: Flexible fuel spray jet penetration distance in step 5 The change pattern over time is calculated by the following formula: in, is the nozzle diameter contraction coefficient, is the spray cross-sectional velocity and volume fraction distribution factor, It is the duration of fuel injection.

3. A computer device comprising a memory and a processor, characterized in that A computer program is stored in the memory. When the processor runs the computer program stored in the memory, the processor executes the method according to any one of claims 1 to 2.

4. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 2 are implemented.

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