CN120083622A

CN120083622A - Fuel supply system, fuel mixing method and gas engine

Info

Publication number: CN120083622A
Application number: CN202510394935.0A
Authority: CN
Inventors: 廖述智; 邓海军; 雷爱国; 商建; 陈磊
Original assignee: HUNAN LIYU GAS POWER CO Ltd
Current assignee: HUNAN LIYU GAS POWER CO Ltd
Priority date: 2025-03-31
Filing date: 2025-03-31
Publication date: 2025-06-03

Abstract

The present application discloses a fuel supply system, a fuel mixing method and a gas engine, and relates to the technical field of gas engines. The fuel supply system includes a first fuel supply module, a second fuel supply module and a combustion module. The first fuel supply module is used to mix gas fuel with air to form a first mixed gas with a gas fuel concentration lower than the ignition limit; the second fuel supply module provides a second mixed gas with a gas fuel concentration higher than the ignition limit; the output end of the second fuel supply module is connected to the output end of the first fuel supply module, so that the first mixed gas and the second mixed gas are mixed to form a combustible mixed gas with a gas fuel concentration within the ignition limit, and the output end of the first fuel supply module is also connected to the combustion module so that the combustible mixed gas is input into the combustion module. The fuel supply system provided by the present application can limit the engine backfire combustion range between the first fuel supply module and the combustion module, reducing the risk of explosion.

Description

Fuel supply system, fuel mixing method, and gas engine

Technical Field

The application relates to the technical field of gas engines, in particular to a fuel supply system, a fuel mixing method and a gas engine.

Background

The gas mixing process is a key link of the gas engine, and directly affects the combustion efficiency and the emission performance. Common gas mixing modes of gas engines include premixed modes. Premixing means that the fuel gas and air are mixed prior to entering the cylinders, typically in an intake manifold or mixer.

The engine adopting the premixing mode has the risk of tempering, and particularly when the hydrogen content in the fuel gas is higher, the tempering is easier to occur because the hydrogen has the characteristics of high combustion speed and wide ignition range. Once the engine is backfire, all of the combustible gases in the mixer to the intake manifold will ignite, causing an explosion, causing an immeasurable loss.

Disclosure of Invention

In view of the above, the present application provides a fuel supply system, a fuel mixing method and a gas engine, which aim to solve one of the technical problems in the prior art.

In order to achieve the above purpose, the technical scheme adopted by the application is as follows:

In a first aspect, an embodiment of the present application provides a fuel supply system including:

a first fuel supply module for mixing a gaseous fuel with air to form a first mixed gas having a gaseous fuel concentration below an ignition limit;

a second fuel supply module for providing a second mixed gas having a gaseous fuel concentration above an ignition limit;

The output end of the first fuel supply module is communicated with the combustion module so that the combustible mixed gas with the gas fuel concentration within an ignition limit value is formed by mixing the first mixed gas and the second mixed gas, and the output end of the first fuel supply module is also communicated with the combustion module so that the combustible mixed gas is input into the combustion module.

In some embodiments, the first fuel supply module includes:

an air branch for outputting air;

a first fuel branch for outputting gaseous fuel;

The output ends of the air branch and the fuel branch are respectively communicated with the mixer, and the mixer is used for mixing air output by the air branch and gas fuel output by the first fuel branch to form the first mixed gas.

In an alternative embodiment of the first aspect, the first fuel branch comprises a first gas source, a pressure regulating valve and a first gaseous fuel flow control valve, which are in communication in sequence.

In an alternative embodiment of the first aspect, the air branch comprises a second air source, a filter and an air flow control valve, the second air source, the filter, the air flow control valve and the mixer being in communication in sequence.

In an alternative embodiment of the first aspect, the first fuel supply module further comprises a first supercharger, a cooler, a throttle valve and an intake manifold connected in sequence, an output of the mixer being in communication with the first supercharger.

In an alternative embodiment of the first aspect, the second fuel supply module further comprises a second fuel branch for outputting the second mixed gas, and the second mixed gas is mixed with the first mixed gas output by the intake manifold to form the combustible mixed gas.

In an alternative embodiment of the first aspect, the second fuel branch includes a third gas source, a second booster, a second gaseous fuel flow control valve, and a gas outlet pipe that are in communication in sequence, the intake manifold has a plurality of first branch lines, and the gas outlet pipe includes a plurality of second branch lines, one of which is in communication with each of the first branch lines.

In an alternative embodiment of the first aspect, the combustion module comprises a plurality of cylinders, each of which is in communication with one of the first branch lines, the first mixed gas in the first branch line being mixed with the second mixed gas before reaching the cylinders to form the combustible mixed gas, the combustible mixed gas being fed into the cylinders.

In a second aspect, an embodiment of the present application further provides a fuel mixing method, including:

mixing a gaseous fuel with air in a mixer to form a non-combustible mixed gas having a gaseous fuel concentration below an ignition limit;

inputting the non-combustible mixed gas into an intake manifold from a mixer, and then mixing the non-combustible mixed gas with the gas fuel, wherein the concentration of the gas fuel output by the intake manifold is lower than the ignition limit value, so as to form the combustible mixed gas;

and inputting the combustible mixed gas into an engine cylinder for combustion and doing work.

In a third aspect, an embodiment of the present application further provides a gas engine, including the fuel supply system in any one of the above embodiments.

Compared with the prior art, the fuel supply system has the beneficial effects that the fuel supply system comprises a first fuel supply module, a second fuel supply module and a combustion module, wherein the first fuel supply module is used for mixing gas fuel with air to form first mixed gas with gas fuel concentration lower than an ignition limit value, the second fuel supply module is used for providing second mixed gas with gas fuel concentration higher than the ignition limit value, the output end of the second fuel supply module is communicated with the output end of the first fuel supply module so as to enable the first mixed gas and the second mixed gas to be mixed to form combustible mixed gas with gas fuel concentration within the ignition limit value, the output end of the first fuel supply module is also communicated with the combustion module so as to enable the combustible mixed gas to be input into the combustion module, and the second fuel supply module outputs second mixed gas as the first mixed gas, so that the first mixed gas and the second mixed gas are both non-combustible mixed gas, and cannot be ignited.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram showing a structure of a fuel supply system in the related art;

FIG. 2 illustrates one of the structural schematic diagrams of a fuel supply system in some embodiments of the application;

FIG. 3 illustrates a second schematic diagram of a fuel delivery system in accordance with some embodiments of the application;

FIG. 4 illustrates a flow chart of a fuel mixing method in some embodiments of the application.

The main reference numerals are 100-fuel supply system, I-first fuel supply module, II-second fuel supply module, III-combustion module, 31-first air source, 4-pressure regulating valve, 5-first gas fuel flow control valve, 111-second air source, 1-filter, 2-air flow control valve, 6-mixer, 3-gas shut-off valve, 7-first booster, 8-cooler, 9-throttle, 12-intake manifold, 32-third air source, 10-second booster, 11-second gas fuel flow control valve, 13-outlet pipe, 14-cylinder, L1-air branch, L2-first fuel branch, L3-second fuel branch.

Detailed Description

Embodiments of the present application are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the application.

In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present application and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present application.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present application, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.

In the present application, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed, mechanically connected, electrically connected, directly connected, indirectly connected via an intervening medium, or in communication between two elements or in an interaction relationship between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present application, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

As shown in fig. 1, the gas supply system in the related art generally operates on the principle that air is filtered by a filter 10 and then enters an air flow control valve 20, the air flow control valve 20 controls air entering a mixer 50, gas in a gas source 30 enters the mixer 50 after passing through a flow control valve 40, the air and the gas are mixed into a combustible mixed gas by the mixer 50, the combustible mixed gas is pressurized by a booster 60 and cooled by a cooler 70, and then enters an air intake manifold 90 under control of a throttle valve 80, the combustible mixed gas in the air intake manifold 90 enters each cylinder 110 of the engine, and the combustible mixed gas is ignited in the cylinder 110 to perform work.

As can be seen, the combustible mixture flows through supercharger 60, cooler 70, throttle 80, intake manifold 90 and cylinders 110 in that order.

When the engine is backfire, the combustible mixture in the supercharger 60, the cooler 70, the throttle valve 80, and the intake manifold 90 is ignited, causing explosion and great loss.

In view of the above problems, as shown in fig. 2, an embodiment of the present application provides a fuel supply system 100, which is mainly used for supplying fuel gas to a gas engine more safely, and reducing the loss caused by flashback. The fuel supply system 100 includes a first fuel supply module I, a second fuel supply module II, and a combustion module III.

The first fuel supply module I is used for mixing the gas fuel with air to form a first mixed gas with the gas fuel concentration lower than an ignition limit value.

It is understood that gaseous fuel refers to a gas that is capable of being homogeneously mixed with air (or oxygen) over a range of concentrations to form a gas that emits a significant amount of energy during combustion when exposed to a fire source.

The gaseous fuel includes hydrogen (H ₂), carbon monoxide (CO), methane (CH ₄), ethane (C ₂H₆), propane (C ₃H₈), butane (C ₄H₁₀), ethylene (C ₂H₄), propylene (C ₃H₆), butene (C ₄H₈), acetylene (C ₂H₂), propyne (C ₃H₄), butyne (C ₄H₆), hydrogen sulfide (H ₂ S), hydrogen phosphide (PH ₃), and the like.

The gaseous fuel in the first mixed gas is formed by mixing one or more gases of the above gases. The first mixed gas is, for example, natural gas, gas or the like diluted with air and having a gas fuel concentration below the ignition limit. Wherein the natural gas contains methane as main component and small amount of ethane, butane, pentane, etc. The main components of the gas are CO, hydrogen, alkane, alkene, arene and the like.

In one embodiment, the first mixed gas is made non-combustible by reducing the mass ratio of the gaseous fuel in the first mixed gas for the purpose of making the gaseous fuel concentration in the first mixed gas below the ignition limit.

For example, when the methane accounts for 5% -15% of the mass of the first mixed gas, the first mixed gas is a combustible mixed gas and is easy to ignite, and when the methane accounts for 3% of the mass of the first mixed gas, the methane concentration is lower than the lowest ignition limit value, and the first mixed gas is a non-combustible mixed gas.

The second fuel supply module II is used for providing a second mixed gas with a gaseous fuel concentration higher than the ignition limit value.

The gas fuel of the second mixed gas is formed by mixing one or more of hydrogen (H2), carbon monoxide (CO), methane (CH 4), ethane (C2H 6), propane (C3H 8), butane (C4H 10), ethylene (C2H 4), propylene (C3H 6), butene (C ₄H₈), acetylene (C ₂H₂), propyne (C ₃H₄), butyne (C ₄H₆), hydrogen sulfide (H ₂ S) and phosphine (PH ₃). Illustratively, the second mixed gas is natural gas, coal gas, or the like.

In one embodiment, the second mixed gas is made non-combustible by increasing the mass ratio of the gaseous fuel in the second mixed gas for the purpose of making the gaseous fuel concentration in the second mixed gas higher than the ignition limit.

For example, when the methane accounts for 5% -15% of the mass of the second mixed gas, the second mixed gas is a combustible mixed gas and is easy to ignite, and when the methane accounts for 20% of the mass of the second mixed gas, the methane concentration is higher than the highest ignition limit value, and the second mixed gas is a non-combustible mixed gas.

In this embodiment, the composition and concentration distribution of the gas fuel in the first mixed gas and the gas fuel in the second mixed gas are the same. Therefore, the number and the types of air sources can be reduced, the cost is reduced, the types of waste gas formed by burning the combustible mixed gas are also reduced, the waste gas is convenient to intensively treat, and the cost is reduced. For example, natural gas is used as the gas fuel in the first mixed gas and as the gas fuel in the second mixed gas.

In other embodiments, the composition and concentration profile of the gaseous fuel in the first mixed gas and the gaseous fuel in the second mixed gas may be adjusted as desired.

As shown in fig. 2 and 3, the output end of the second fuel supply module II is communicated with the output end of the first fuel supply module I to mix the first mixed gas and the second mixed gas to form a combustible mixed gas with a gas fuel concentration within an ignition limit value, and the output end of the first fuel supply module I is also communicated with the combustion module III to input the combustible mixed gas into the combustion module III.

The combustible mixed gas is the mixed gas with the gas fuel ratio within the ignition limit value, and is easy to ignite. For example, the gas fuel in the first mixed gas and the gas fuel in the second mixed gas are methane, the mass ratio of methane in the first mixed gas is lower than 5%, the mass ratio of methane in the second mixed gas is higher than 15%, the first mixed gas and the second mixed gas are mixed, the mass ratio of methane in the combustible mixed gas is 5% -15%, the combustible mixed gas is easy to ignite, and the combustible mixed gas is input into the combustion module III for combustion work.

Since the output end of the first fuel supply module I outputs the first mixed gas and the second fuel supply module II outputs the second mixed gas, the first mixed gas and the second mixed gas are both non-combustible mixed gas and cannot be ignited. When the engine is backfire, the backfire process is cut off at the output end of the first fuel supply module I and the output end of the second fuel supply module II, and the combustible mixed gas easy to burn in the whole fuel supply system 100 is arranged between the first fuel supply module I and the combustion module III, so that the backfire combustion range is limited between the first fuel supply module I and the combustion module III, the explosion risk is reduced, and the fault occurrence is reduced.

In addition, as shown in fig. 1, the related art has a long pipe distance between the flow control valve 40 and the cylinder 110, resulting in a slow air-fuel ratio adjustment of the gaseous fuel entering the cylinder 110, reducing the dynamic response capability of the engine.

In order to solve the above problems, as shown in fig. 2 and 3, the present application sets the second fuel supply module II to adjust the concentration of the gas fuel in the first mixed gas entering the pipe of the previous small section of the cylinder 14, so as to increase the concentration of the gas fuel in the first mixed gas into the combustible mixed gas, and adjust the concentration of the gas fuel in the cylinder 14 in a short time, thereby greatly improving the dynamic response capability of the engine.

In some embodiments, as shown in fig. 2 and 3, the first fuel supply module I includes an air branch L1, a first fuel branch L2, and a mixer 6.

In one embodiment, air branch L1 is used to output air. Oxygen in the air is used as combustion improver to be mixed with gas fuel. In some embodiments, the air branch L1 may output only oxygen, or other gases containing oxygen.

The first fuel branch L2 is used for outputting the gaseous fuel. The output ends of the air branch L1 and the fuel branch are respectively communicated with a mixer 6, and the mixer 6 is used for mixing air and gas fuel output by the air branch L1 to form first mixed gas.

In one embodiment, to improve the regulation efficiency, the first fuel leg L2 outputs a gaseous fuel concentration slightly above or within the ignition limit.

Illustratively, still taking gaseous fuel methane as an example, the methane concentration in the gas output by the first fuel leg L2 is 5% -20%. Thus, the concentration of methane is diluted with air in the mixer 6 to form a first mixed gas having a methane concentration of less than 5%.

It will be appreciated that when the gas fuel concentration in the gas output by the first fuel leg L2 is above the ignition limit, the risk of flashback of the fuel supply system 100 can be further reduced.

By providing the mixer 6 to thoroughly mix the air and the gaseous fuel, the combustion of the gas entering the combustion module III is more complete, the fluctuation of the engine speed is smaller, the electrical efficiency is higher, and the cylinder exhaust temperature is lower.

In some embodiments, as shown in fig. 2 and 3, the first fuel branch L2 includes a first gas source 31, a pressure regulating valve 4, and a first gaseous fuel flow control valve 5, and the first gas source 31, the pressure regulating valve 4, the first gaseous fuel flow control valve 5, and the mixer 6 are in communication in sequence.

Wherein the first gas source 31 is used to provide a raw gas, and the concentration of the gas fuel in the raw gas can be higher or lower than the ignition limit, and can be within the ignition limit. If the gas fuel concentration in the feed gas of the first gas source 31 is below the ignition limit, in some embodiments, no air mixing is added to the feed gas and the air flow control valve 2 is in the fully closed position.

The pressure regulating valve 4 is used to regulate the gas pressure and the first gaseous fuel flow control valve 5 is used to regulate the flow of gas to the mixer 6.

In some embodiments, air branch L1 includes a second air source 111, a filter 1, and an air flow control valve 2, with second air source 111, filter, air flow control valve 2, and mixer 6 communicating in sequence.

The second air source 111 is used to provide air. The filter 1 is used for filtering impurities in the air, and the air flow control valve 2 is used for adjusting the flow rate of the gas input into the mixer 6, thereby adjusting the concentration of the gas fuel in the first mixed gas.

In some embodiments, as shown in fig. 2 and 3, the first fuel supply module I further includes a first supercharger 7, a cooler 8, a throttle valve 9, and an intake manifold 12 connected in this order, and an output end of the mixer 6 communicates with the first supercharger 7.

The first supercharger 7 employs an engine supercharger or an external supercharging device. The cooler 8 adopts an intercooler for cooling. The first mixed gas output from the mixer 6 passes through the first supercharger 7, the cooler 8, and the throttle valve 9 in this order, and is controlled by the throttle valve 9 to enter the intake manifold 12. The pipeline path of the mixer 6 and the combustion module III is longer, so that the first mixed gas is uniformly mixed, the full combustion is facilitated, the fluctuation of the rotation speed of the engine is smaller, the electric efficiency is higher, and the temperature of the cylinder exhaust is lower.

In some embodiments, as shown in fig. 2 and 3, the second fuel supply module II further includes a second fuel leg L3. The second fuel branch L3 is configured to output a second mixed gas, and the second mixed gas is mixed with the first mixed gas output from the intake manifold 12 to form a combustible mixed gas.

The second mixed gas and the first mixed gas enter the combustion module III after being mixed, and as the pipeline path between the second fuel branch L3 and the combustion module III is shorter, the condition that the combustible mixed gas is not fully mixed exists, the insufficient mixing can lead to insufficient combustion of the fuel gas, and the problems of high fluctuation of the engine rotating speed, low electrical efficiency, high cylinder exhaust temperature and the like are caused.

According to the application, partial gas fuel in the combustible mixed gas is fully mixed with air in the first fuel supply module I, so that adverse effects caused by insufficient mixing of the combustible mixed gas are greatly reduced, and the advantage of short pipeline distance between the second fuel supply module II and the combustion module III is utilized, so that the response efficiency of the engine is greatly improved by the residual partial gas fuel in the combustible mixed gas.

In some embodiments, as shown in fig. 2 and 3, the second fuel leg L3 includes a third gas source 32, a second booster 10, a second gaseous fuel flow control valve 11, and a gas outlet pipe 13 in communication in that order.

In one embodiment, the third air source 32 and the first air source 31 may be the same air source, which reduces the cost and simplifies the distribution of the pipelines. It will be appreciated that the third air supply 32 and the first air supply 31 may be provided as different air supplies as desired.

It should be noted that, as shown in fig. 3, when the third air source 32 and the first air source 31 are the same air source, for example, the third air source 32 and the first air source 31 are both gas shutoff valves 3 connected to an external air source. The pressure regulating valve 4 is arranged between the first gas fuel flow control valve 5 and the gas stop valve 3, so that the influence of gas pressure fluctuation caused by the second booster 10 on the inlet pressure of the first gas fuel flow control valve 5 can be greatly reduced, and the influence of the second booster 10 on the gas flow control precision of the first gas fuel flow control valve 5 can be reduced.

The second supercharger 10 may be a supercharging device on the engine or may be a supercharging device outside the engine.

The second gaseous fuel flow control valve 11 is used to control the flow of the second mixed gas into the outlet pipe 13. The second gaseous fuel flow control valve 11 is linked with the throttle valve 9 to adjust the concentration of gaseous fuel in the combustible mixed gas.

In some embodiments, as shown in fig. 2 and 3, the intake manifold 12 has a plurality of first branch lines, and the outlet pipe 13 includes a plurality of second branch lines, one of which communicates with each of the first branch lines. The first mixed gas entering each cylinder 14 is allowed to mix with the second mixed gas to form a combustible mixed gas.

In some embodiments, the combustion module III includes a plurality of cylinders 14, each cylinder 14 being in communication with a respective first branch line, the first mixture within the first branch line being mixed with the second mixture to form a combustible mixture prior to reaching the cylinder 14, the combustible mixture being fed into the cylinder 14. When the engine is backfire, the backfire process is cut off at the output end of the first fuel supply module I and the output end of the second fuel supply module II, and the combustible mixed gas easy to burn in the whole fuel supply system 100 is arranged between the first fuel supply module I and the combustion module III, so that the backfire combustion range is limited between the first fuel supply module I and the combustion module III, the explosion risk is reduced, and the fault occurrence is reduced.

Referring to fig. 2 and 3 in combination, a method of using the fuel supply system 100 will be explained.

The method comprises the following steps:

The method is applicable to the case that the gas sources in the first gas source 31 and the third gas source 32 are the same, and the gas fuel concentration in the raw material gas is higher than the ignition limit value.

The first fuel supply module I is used for providing a first mixed gas with the concentration of the gas fuel being lower than the ignition limit value. The second fuel supply module II is used for providing a second mixed gas with the gas fuel concentration higher than the ignition limit value.

Still taking methane as an example, the first gas source 31 and the third gas source 32 both provide raw gas with methane concentration of 70%, the raw gas with 70% concentration provided by the first gas source 31 is mixed with air in the mixer 6 to form first mixed gas with concentration of 4%, the first mixed gas with concentration of 4% sequentially passes through the first booster 7, the cooler 8, the throttle valve 9 and the intake manifold 12, the raw gas with concentration of 70% provided by the third gas source 32 is used as second mixed gas, and the first mixed gas with concentration of 4% and the second mixed gas with concentration of 70% sequentially pass through the second booster 10, the second gas fuel flow control valve 11 and the gas outlet pipe 13, and the first mixed gas with concentration of 70% is mixed to form combustible mixed gas with concentration of 5% -15% before entering the cylinder 14.

The second method is as follows:

the method is applicable to the fact that the gas sources in the first gas source 31 and the third gas source 32 are different, the gas fuel concentration in the raw material gas of the first gas source 31 is lower than the ignition limit value, and the gas fuel concentration in the raw material gas of the third gas source 32 is higher than the ignition limit value. In this method, the air branch L1 of the first fuel supply module I is closed.

Still taking methane as an example, the first gas source 31 provides a raw gas with a methane concentration of 4%, and since the methane concentration in the raw gas is below the lowest ignition limit, it is unnecessary to mix the raw gas with air, and the raw gas is used as the first mixed gas, so that the air branch L1 of the first fuel supply module I is closed.

The first mixed gas passes through the pressure regulating valve 4, the first gaseous fuel flow control valve 5, the mixer 6, the first supercharger 7, the cooler 8, the throttle valve 9, and the intake manifold 12 in this order. The third gas source 32 provides a raw gas with a methane concentration of 80%, which is used as a second mixed gas, and the second mixed gas sequentially passes through the second booster 10, the second gas fuel flow control valve 11 and the gas outlet pipe 13, and the first mixed gas with a concentration of 4% and the second mixed gas with a concentration of 80% are mixed to form a combustible mixed gas with a concentration of 5% -15% before entering the cylinder 14.

And a third method:

the method is applicable to the fact that the gas sources in the first gas source 31 and the third gas source 32 are different, the concentration of the gas fuel in the raw material gas provided by the first gas source 31 is within an ignition limit value, and the concentration of the gas fuel in the raw material gas provided by the third gas source 32 is higher than the ignition limit value.

Still taking methane as an example, the first gas source 31 provides a feed gas having a methane concentration of 10%, and the third gas source 32 provides a feed gas having a methane concentration of 70%. The raw material gas with 10% concentration provided by the first gas source 31 is mixed in the mixer 6 through air to form a first mixed gas with 4% concentration, the first mixed gas with 4% concentration sequentially passes through the first booster 7, the cooler 8, the throttle valve 9 and the intake manifold 12, the raw material gas with 70% concentration provided by the third gas source 32 is used as a second mixed gas, sequentially passes through the second booster 10, the second gas fuel flow control valve 11 and the gas outlet pipe 13, and the first mixed gas with 4% concentration and the second mixed gas with 70% concentration are mixed to form a combustible mixed gas with 5% -15% concentration before entering the cylinder 14.

As shown in fig. 4, there is also provided a fuel mixing method according to an embodiment of the present application, including:

in step S10, the gaseous fuel is mixed with air in the mixer 6 to form a non-combustible mixed gas having a gaseous fuel concentration below the ignition limit.

The gas fuel is a gas formed by mixing one or more of hydrogen (H2), carbon monoxide (CO), methane (CH 4), ethane (C2H 6), propane (C3H 8), butane (C4H 10), ethylene (C2H 4), propylene (C3H 6), butene (C ₄H₈), acetylene (C ₂H₂), propyne (C ₃H₄), butyne (C ₄H₆), hydrogen sulfide (H ₂ S), and phosphine (PH ₃). By non-combustible gas mixture is meant a gas having a gaseous fuel concentration below the ignition limit.

Taking gaseous fuel methane as an example, the concentration of methane in the nonflammable mixture is less than 5%.

In step S20, the non-combustible mixed gas is input into the intake manifold 12 from the mixer 6, and the non-combustible mixed gas with the gas fuel having the gas fuel concentration lower than the ignition limit value output from the intake manifold 12 is mixed with the gas fuel to form the combustible mixed gas.

Wherein the intake manifold 12 has a plurality of branch pipes, each of which communicates with one of the cylinders 14.

The non-combustible mixture gas output from the intake manifold 12 refers to a gas flowing from the branch pipe to the cylinder 14.

The combustible mixed gas refers to a gas whose gas fuel concentration is within a limit. Taking gaseous fuel methane as an example, the concentration of methane in the combustible mixed gas is 5% -15%.

In step S30, the combustible mixture is input into the engine cylinder 14 for combustion work.

The present application also provides a gas engine comprising the fuel supply system 100 of any of the embodiments described above. By fully mixing part of the gas fuel in the combustible mixed gas with air in the first fuel supply module I, the adverse effect caused by insufficient mixing of the combustible mixed gas is greatly reduced, and the response speed of the engine is improved by quickly changing the air-fuel ratio of the combustible mixed gas by utilizing the advantage of short pipeline distance between the second fuel supply module II and the combustion module III.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

While embodiments of the present application have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the application, and that variations, modifications, alternatives and variations may be made to the above embodiments by one of ordinary skill in the art within the scope of the application.

Claims

1. A fuel supply system, comprising:

2. The fuel supply system of claim 1, wherein the first fuel supply module comprises:

an air branch for outputting air;

a first fuel branch for outputting gaseous fuel;

3. The fuel supply system of claim 2, wherein the first fuel branch comprises a first gas source, a pressure regulating valve, and a first gaseous fuel flow control valve, the first gas source, the pressure regulating valve, the first gaseous fuel flow control valve, and the mixer being in communication in sequence.

4. The fuel supply system of claim 2, wherein the air branch includes a second air source, a filter, and an air flow control valve, the second air source, the filter, the air flow control valve, and the mixer communicating in sequence.

5. The fuel supply system of claim 2, wherein the first fuel supply module further comprises a first supercharger, a cooler, a throttle, and an intake manifold connected in sequence, an output of the mixer being in communication with the first supercharger.

6. The fuel supply system of claim 5, wherein the second fuel supply module further comprises a second fuel branch for outputting the second mixed gas, the second mixed gas being mixed with the first mixed gas output by the intake manifold to form the combustible mixed gas.

7. The fuel supply system of claim 6, wherein the second fuel rail includes a third gas source, a second booster, a second gaseous fuel flow control valve, and a gas outlet pipe in sequential communication, the intake manifold having a plurality of first branch lines, the gas outlet pipe including a plurality of second branch lines, one of the second branch lines in corresponding communication with one of the first branch lines.

8. The fuel supply system of claim 7, wherein the combustion module includes a plurality of cylinders, each of the cylinders being in communication with one of the first branch lines, the first mixed gas in the first branch line being mixed with the second mixed gas to form the combustible mixed gas before reaching the cylinder, the combustible mixed gas being input into the cylinders.

9. A fuel mixing method characterized by comprising:

10. A gas engine comprising the fuel supply system according to any one of claims 1 to 8.