Control method for an engine, engine device and system

Abstract

This application provides a control method, engine device, and system for an engine. The method includes: controlling the engine to operate in a dual-fuel mode; controlling heated gas to be introduced into a target area at a first flow rate; acquiring a first temperature of the target area and a first methanol substitution rate after a preset time; if the first methanol substitution rate is greater than or equal to a preset substitution rate, controlling the heated gas to be introduced into the target area at the first flow rate; if the first methanol substitution rate is less than the preset substitution rate and the first temperature is less than the preset temperature, controlling the heated gas to be introduced into the target area at a second flow rate; acquiring a second temperature of the target area and a second methanol substitution rate after a preset time; and if the second methanol substitution rate is greater than or equal to the preset substitution rate, controlling the heated gas to be introduced into the target area at the second flow rate. This application solves the problem that in existing methanol injectors, when methanol is injected into the intake manifold, methanol tends to adhere to the inner wall of the intake manifold, resulting in a low methanol substitution rate.

Description

Technical Field

[0001] This application relates to the field of engine technology, and more specifically, to an engine control method, an engine device, and an engine control system. Background Technology

[0002] With increasingly stringent emission requirements for internal combustion engines and growing demand for clean and low-carbon fuels, methanol is increasingly being used in engines due to its wide availability, clean combustion, and relatively low cost. Especially in methanol-diesel dual-fuel engines, methanol is typically injected into the intake manifold via a methanol injector, mixing with the air entering the cylinder. Diesel fuel is then used for ignition, thus partially replacing diesel fuel with methanol, achieving the goals of reducing emissions and improving fuel economy.

[0003] However, in existing technologies, after methanol is injected into the intake manifold by the methanol injector, the methanol easily impacts and adheres to the inner wall of the intake manifold, resulting in poor methanol atomization and incomplete vaporization. Consequently, the amount of methanol entering the combustion chamber and actually participating in combustion is reduced. The large amount of methanol adhering to the wall not only affects the uniform mixing of methanol and air but also reduces the methanol combustion efficiency, ultimately leading to a low methanol substitution rate, which fails to meet the requirements of dual-fuel engines for efficient methanol utilization. Summary of the Invention

[0004] The main objective of this application is to provide an engine control method, engine device, and engine control system to at least solve the problem that when existing methanol injectors inject methanol into the intake manifold, methanol tends to adhere to the inner wall of the intake manifold, resulting in a low methanol substitution rate.

[0005] To achieve the above objectives, according to one aspect of this application, an engine control method is provided, comprising: controlling the engine to operate in a dual-fuel mode and controlling heating gas to be introduced into a target area at a first flow rate, the target area being the intersection of the injection axis of a methanol injector and the inner wall of the intake manifold, the dual-fuel mode being an operating mode in which methanol and diesel jointly participate in combustion; obtaining a first temperature of the target area and obtaining a first methanol substitution rate after a preset time, the heating gas being gas compressed after engine intake; when the first methanol substitution rate is greater than or equal to a preset substitution rate, controlling the heating gas to be introduced into the target area at the first flow rate; when the first methanol substitution rate is less than the preset substitution rate and the first temperature is less than a preset temperature, controlling the heating gas to be introduced into the target area at a second flow rate, and obtaining a second temperature of the target area and obtaining a second methanol substitution rate after the preset time, the second flow rate being greater than the first flow rate; when the second methanol substitution rate is greater than or equal to the preset substitution rate, controlling the heating gas to be introduced into the target area at the second flow rate.

[0006] Optionally, obtaining the first methanol substitution rate includes: controlling the engine to operate in pure diesel mode under preset operating conditions, and obtaining a first diesel consumption within a preset time period; controlling the engine to operate in dual-fuel mode under the preset operating conditions, and obtaining a second diesel consumption within the preset time period after the heating gas is introduced into the target area at the first flow rate for the preset duration; and determining the first methanol substitution rate based on the first diesel consumption and the second diesel consumption.

[0007] Optionally, determining the first methanol substitution rate based on the first diesel consumption and the second diesel consumption includes: determining the difference between the first diesel consumption and the second diesel consumption; and determining the first methanol substitution rate as the quotient of the difference and the first diesel consumption.

[0008] Optionally, after obtaining the first temperature of the target area and the first methanol substitution rate after a preset time, the method further includes: if the first temperature is greater than the preset temperature and the first methanol substitution rate is less than the preset substitution rate, controlling the heating gas to be introduced into the target area at the first flow rate.

[0009] Optionally, the method further includes: when the temperature of the target area is greater than or equal to the preset temperature and the methanol substitution rate is less than the preset substitution rate, outputting an alarm message to indicate that the temperature of the target area is greater than or equal to the preset temperature and the methanol substitution rate has not reached the preset substitution rate.

[0010] Optionally, the method further includes: when the methanol substitution rate is greater than or equal to the target substitution rate, determining the flow rate of the heating gas corresponding to the target substitution rate as the target flow rate, wherein the target substitution rate is greater than the preset substitution rate; determining the temperature of the target area corresponding to the target substitution rate as the target temperature, and controlling the heating gas to be introduced into the target area according to the target flow rate and the target temperature.

[0011] According to another aspect of this application, an engine device is provided, the engine device being controlled by any of the engine control methods described above, comprising: a cylinder head having an intake manifold and a water jacket, wherein a first gap thickness between the water jacket and the inner wall of the intake manifold in a target area is greater than a second gap thickness between the water jacket and the inner wall of the intake manifold in a non-target area, the target area being the intersection area of ​​the injection axis of a methanol injector and the inner wall of the intake manifold; and a methanol injector disposed on the cylinder head for injecting methanol into the intake manifold.

[0012] Optionally, the thickness of the first gap is 1.3-1.5 times the thickness of the second gap.

[0013] Optionally, the target area is a circular area with a radius of 10mm-15mm.

[0014] According to another aspect of this application, an engine control system is provided, comprising: one or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the one or more programs including methods for performing any one of the methods described.

[0015] By applying the technical solution of this application, controlling the engine to operate in dual-fuel mode and introducing heated gas into the target area of ​​the intake manifold where the injection axis acts on the methanol injector, the local temperature of the area where methanol easily adheres to the wall can be increased. This reduces methanol adhesion and liquid film formation on the intake manifold wall, promotes methanol atomization and vaporization, and allows more methanol to enter the combustion chamber with the intake air to participate in combustion. Simultaneously, by obtaining the target area temperature at different flow rates and determining the corresponding methanol substitution rate, a more suitable heating gas flow rate can be gradually matched. While ensuring that the target area temperature does not exceed the preset temperature, the methanol substitution rate is increased, thereby improving the methanol utilization effect and combustion stability of the dual-fuel engine. This solves the problem that in existing methanol injectors, when methanol is injected into the intake manifold, methanol easily adheres to the inner wall of the intake manifold, resulting in poor atomization and vaporization effects and a low methanol substitution rate. Attached Figure Description

[0016] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0017] Figure 1 A schematic flowchart of an engine control method according to an embodiment of this application is shown;

[0018] Figure 2 A schematic diagram of an engine device provided according to an embodiment of this application is shown;

[0019] Figure 3 A schematic flowchart of another engine control method provided according to an embodiment of this application is shown.

[0020] The above figures include the following reference numerals:

[0021] 100. Cylinder head; 110. Water jacket; 120. Target area; 130. Methanol injector. Detailed Implementation

[0022] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0023] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0024] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0025] As described in the background section, when existing methanol injectors inject methanol into the intake manifold, the methanol tends to adhere to the inner wall of the manifold, resulting in a low methanol substitution rate. To solve the above-mentioned technical problems, embodiments of this application provide an engine control method, an engine device, and an engine control system.

[0026] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0027] Figure 1 This is a flowchart of an engine control method according to an embodiment of this application. Figure 1 As shown, the method includes the following steps:

[0028] Step S101: Control the engine to operate in dual-fuel mode and control the heating gas to be introduced into the target area at a first flow rate. The target area is the intersection of the injection axis of the methanol injector and the inner wall of the intake manifold. The dual-fuel mode is an operating mode in which methanol and diesel participate in combustion together.

[0029] Specifically, by activating the engine to the appropriate operating state and applying heating to the target area, targeted thermal regulation can be performed on the methanol-adhesive wall areas during engine operation. Since this location is where methanol is more likely to form adhesion and a liquid film after injection, localized heating of this area helps to weaken the methanol's tendency to adhere to the wall, improves methanol evaporation conditions, and thus creates conditions for subsequently increasing the proportion of methanol participating in combustion.

[0030] Step S102: After a preset time, obtain the first temperature of the target area and obtain the first methanol substitution rate. The heating gas is the gas after the engine intake is compressed.

[0031] Specifically, the first temperature is used to reflect the current local heating state, and the methanol substitution rate is used to reflect the actual effect of methanol participating in combustion.

[0032] Step S103: When the first methanol substitution rate is greater than or equal to the preset substitution rate, the heating gas is controlled to be introduced into the target area at the first flow rate.

[0033] Specifically, when the first methanol substitution rate reaches the preset substitution rate, it indicates that the current heating conditions are sufficient to meet the requirements for methanol substitution effect, so the current flow rate can be maintained for control.

[0034] Step S104: When the first methanol substitution rate is less than the preset substitution rate and the first temperature is less than the preset temperature, the heating gas is controlled to be introduced into the target area at a second flow rate, and after the preset time, the second temperature of the target area is obtained, and the second methanol substitution rate is obtained, wherein the second flow rate is greater than the first flow rate.

[0035] Specifically, when the first methanol substitution rate has not yet reached the preset substitution rate, and the current temperature is still below the preset temperature, it indicates that the existing heating intensity is insufficient, but there is still room to further improve the local thermal conditions. In this case, by increasing the heating gas flow rate and obtaining the second temperature and the second methanol substitution rate again, the control results after increasing the flow rate are reassessed. By comparing the methanol substitution effect after increasing the flow rate, it can be determined whether the expected control objective has been achieved after increasing the flow rate.

[0036] Step S105: When the second methanol substitution rate is greater than or equal to the preset substitution rate, the heating gas is controlled to be introduced into the target area at the second flow rate.

[0037] Specifically, when the second methanol substitution rate reaches the preset substitution rate, it indicates that the increased heating flow rate can meet the requirements for methanol substitution effect.

[0038] Through the above embodiments, by controlling the engine to operate in dual-fuel mode and introducing heated gas into the target area of ​​the intake manifold where the injection axis acts on the methanol injector, the local temperature of the area where methanol easily adheres to the wall can be increased, reducing methanol adhesion and liquid film formation on the intake manifold wall, promoting methanol atomization and vaporization, and allowing more methanol to enter the combustion chamber with the intake air to participate in combustion. Simultaneously, by obtaining the target area temperature at different flow rates and determining the corresponding methanol substitution rate, a more suitable heating gas flow rate can be gradually matched. While ensuring that the target area temperature does not exceed the preset temperature, the methanol substitution rate is increased, thereby improving the methanol utilization effect and combustion stability of the dual-fuel engine. This solves the problem that when existing methanol injectors inject methanol into the intake manifold, methanol easily adheres to the inner wall of the intake manifold, resulting in poor atomization and vaporization effects and a low methanol substitution rate.

[0039] In some embodiments of this application, the control process is not limited to only two flow rate adjustments. When the second methanol substitution rate obtained under the second flow rate is still less than the preset substitution rate, and the second temperature of the target area is still less than the preset temperature, it indicates that the current heating intensity is still insufficient to achieve the required methanol substitution effect, and the target area still has room for further temperature increases. In this case, the flow rate of the heating gas can be increased further, allowing the heating gas to enter the target area at a higher flow rate. After a corresponding preset time, the temperature of the target area and the corresponding methanol substitution rate are obtained again to continue to judge the control effect under the current heating conditions. Further, in the subsequent cyclic adjustment process, if the current methanol substitution rate reaches the target requirement, the current heating gas flow rate and the current target area temperature can be determined as subsequent control parameters, and the heating gas is continuously controlled to enter the target area according to these control parameters. If the current methanol substitution rate still does not reach the target requirement, it is continued to judge whether the current target area temperature has reached the temperature limit condition; when the current target area temperature has not reached the upper limit, the heating gas flow rate can be increased further; when the current target area temperature reaches the temperature limit condition, the heating intensity is no longer increased to avoid excessively high local temperatures. In other words, the cyclic adjustment process in this application is as follows: introduce heating gas at the current flow rate—obtain the current temperature—obtain the current methanol substitution rate—determine whether the methanol substitution rate meets the standard—if it does not meet the standard, determine whether the temperature has reached the limit condition—if the limit condition has not been reached, continue to increase the flow rate and repeat the above process until the methanol substitution rate meets the requirement or the temperature reaches the limit condition.

[0040] In some embodiments of this application, multiple temperatures and methanol substitution rates obtained under different flow conditions during the circulation process can be analyzed and compared. When a better methanol substitution rate exists among the multiple methanol substitution rates corresponding to multiple temperatures, the temperature and flow rate corresponding to the better methanol substitution rate can be further determined as the target temperature and target flow rate. In other words, it is not only necessary to determine whether the methanol substitution rate meets the preset requirements, but also to further screen out the operating conditions with better methanol substitution effect among multiple operating conditions that meet the preset requirements, and use the flow rate and temperature corresponding to the operating condition as subsequent long-term control parameters.

[0041] For example, without introducing heating gas, the initial temperature T0 of the target area is obtained. Then, heating gas is introduced into the target area at a first flow rate Z1. After a preset time, the first temperature T1 of the target area is obtained, along with the corresponding first methanol substitution rate K1. If K1 does not reach the preset substitution rate, the heating gas flow rate is increased to a second flow rate Z2. After the aforementioned preset time, the second temperature T2 and the corresponding second methanol substitution rate K2 are obtained. Subsequently, the heating gas flow rate is increased incrementally in the same manner, sequentially obtaining T3, T4…Tn and their corresponding methanol substitution rates K3, K4…Kn. This forms multiple temperature points within the temperature range of T1 to Tn and their corresponding methanol substitution rates. For example, the engine is operated under preset conditions, with a target area wall temperature increase of 5°C to 10°C as the initial flow rate setting benchmark. The first flow rate Z1 is taken as 1% to 2% of the total engine intake flow rate, and the flow rate is increased incrementally from 20% to 50% of Z1. After Z1, Z2, Z3, Z4, and Z5 are applied respectively, corresponding temperatures T1, T2, T3, T4, and T5, and corresponding methanol substitution rates K1, K2, K3, K4, and K5 are obtained sequentially. When comparing the methanol substitution rates corresponding to each temperature point, if K4 is determined to be the optimal methanol substitution rate within the range of T1 to T5, then T4 is determined as the target temperature, and the flow rate Z4 corresponding to T4 is determined as the target flow rate. In subsequent control processes, the heating gas is controlled to flow into the target area according to the aforementioned target flow rate and target temperature. Further, in some embodiments, if the target area temperature continues to rise as the heating gas flow rate continues to increase, but the methanol substitution rate does not further increase, or even decreases, then the temperature and flow rate corresponding to the previous temperature point can be used as subsequent control parameters. For example, when the methanol substitution rate Kn corresponding to Tn is not better than the methanol substitution rate Kn-1 corresponding to Tn-1, Tn-1 can be determined as the target temperature, Zn-1 as the target flow rate, and this target flow rate is maintained in subsequent operation to keep the target area in a state more conducive to methanol atomization and vaporization. Furthermore, in some embodiments, the temperature of the target area can be controlled within the range of 80°C to 120°C. When the temperature reaches the upper limit, even if the heating gas flow rate is further increased, the temperature of the target area will no longer increase. Instead, based on the multiple methanol substitution rates already obtained, the temperature and flow rate corresponding to the better methanol substitution rate are selected as subsequent control parameters. In this way, under the premise of meeting the temperature limit conditions, the control condition with better methanol substitution effect can be screened out.

[0042] In one alternative, obtaining the first methanol substitution rate includes: controlling the engine to operate in pure diesel mode under preset operating conditions, and obtaining a first diesel consumption within a preset time period; controlling the engine to operate in dual-fuel mode under the preset operating conditions, and obtaining a second diesel consumption within the preset time period after the heating gas is introduced into the target area at the first flow rate for the preset duration; and determining the first methanol substitution rate based on the first diesel consumption and the second diesel consumption.

[0043] In the above embodiments, by obtaining the first diesel consumption in pure diesel mode and the second diesel consumption in dual-fuel mode under the same preset operating conditions, and determining the first methanol substitution rate based on the two, the substitution effect of methanol on diesel can be quantitatively characterized under a unified operating condition benchmark. This avoids interference from changes in speed, load, or operating status on the substitution rate judgment results, and improves the accuracy and comparability of the methanol substitution rate acquisition results. At the same time, after the heating gas is introduced into the target area at a first flow rate and passes through a preset time, the second diesel consumption in dual-fuel mode is obtained. This can directly reflect the improved methanol atomization and vaporization effect after heating the target area to the diesel consumption change, thereby more accurately evaluating the degree of methanol's actual participation in combustion under the heating conditions corresponding to the first flow rate. Furthermore, by comparing the first diesel consumption and the second diesel consumption, a basis can be provided for subsequent judgment on whether the current heating flow rate meets the preset substitution rate requirements, thereby providing quantitative support for determining whether to maintain the first flow rate or continue to adjust the heating gas flow rate. This makes the engine control process more targeted and reliable, and is conducive to improving methanol utilization and dual-fuel combustion effect.

[0044] In another alternative, determining the first methanol substitution rate based on the first diesel consumption and the second diesel consumption includes: determining the difference between the first diesel consumption and the second diesel consumption; and determining the first methanol substitution rate as the quotient of the difference and the first diesel consumption.

[0045] In the above embodiments, by first determining the difference between the first diesel consumption and the second diesel consumption, the amount of diesel consumed by methanol under dual-fuel operation can be directly obtained, thus reflecting the substitution effect brought about by methanol's participation in combustion in an intuitive difference form. Furthermore, the quotient of the above difference and the first diesel consumption represents the first methanol substitution rate, which can normalize the amount of diesel replaced relative to the benchmark diesel consumption in pure diesel mode, so that the obtained methanol substitution rate reflects the relative degree of methanol substitution for diesel, thereby improving the comparability of the substitution rate evaluation results. Using this method, it can avoid the problem that the second diesel consumption alone is not enough to accurately reflect the contribution of methanol substitution, and can also provide a clear quantitative basis for subsequent judgment on whether the methanol substitution effect corresponding to the current heating flow rate meets the preset requirements. This is conducive to targeted adjustment of the heating gas flow rate based on the substitution rate results, making the control process easier to implement, and is conducive to improving methanol utilization and the combustion optimization effect of dual-fuel engines.

[0046] In some exemplary embodiments, after obtaining the first temperature of the target area and the first methanol substitution rate after a preset time, the method further includes: when the first temperature is greater than the preset temperature and the first methanol substitution rate is less than the preset substitution rate, controlling the heating gas to be introduced into the target area at the first flow rate.

[0047] In the above embodiments, after obtaining the first temperature and the first methanol substitution rate of the target area, if the first temperature is greater than the preset temperature and the first methanol substitution rate is still less than the preset substitution rate, the heating gas is continued to be introduced into the target area at the first flow rate. This indicates that the temperature of the target area has reached the corresponding limit under the current operating conditions, and the heating gas flow rate is no longer blindly increased, thereby avoiding an increase in heat load due to a further increase in local temperature. At the same time, if the methanol substitution rate has not yet reached the preset requirement, the first flow rate is still maintained to heat the target area, which can keep the target area at its current temperature state and avoid the rapid drop in temperature of the target area due to the cessation of heating, thereby weakening the inhibitory effect on methanol adhesion.

[0048] In other exemplary embodiments, when the temperature of the target area is greater than or equal to the preset temperature and the methanol substitution rate is less than the preset substitution rate, an alarm message is output to indicate that the temperature of the target area is greater than or equal to the preset temperature and the methanol substitution rate has not reached the preset substitution rate.

[0049] In the above embodiments, by outputting alarm information when the temperature in the target area is greater than or equal to the preset temperature and the methanol substitution rate is still less than the preset substitution rate, the system can promptly report the abnormal operating condition to the control system or operator when the methanol substitution effect fails to meet expectations and the local temperature adjustment space is limited. This allows the system to promptly identify that simply increasing the temperature in the target area is no longer sufficient to further improve the methanol substitution rate, thereby avoiding the problems of excessive local heat load, over-control, or increased system operation risks that may result from blindly increasing the heating intensity. At the same time, the alarm information can also provide a clear basis for subsequent manual intervention, adjustment of methanol injection parameters, optimization of operating conditions, or switching of control strategies, so that the engine can still maintain a relatively stable and controllable operating state under temperature constraints, thereby improving the safety, monitorability, and reliability of the entire control process.

[0050] In some exemplary embodiments of this application, when the methanol substitution rate is greater than or equal to the target substitution rate, the flow rate of the heating gas corresponding to the target substitution rate is determined as the target flow rate, and the target substitution rate is greater than the preset substitution rate; the temperature of the target area corresponding to the target substitution rate is determined as the target temperature, and the heating gas is controlled to be introduced into the target area according to the target flow rate and the target temperature.

[0051] In the above embodiments, the control parameters corresponding to the achievement of a high methanol substitution effect are fixed because the methanol substitution rate directly reflects the effect of methanol participation in combustion under the current control conditions. When the methanol substitution rate reaches the target substitution rate, it indicates that the heating gas flow rate and target area temperature can support a good methanol substitution effect. Therefore, the specific flow rate and temperature parameters corresponding to this state are further clarified to avoid unclear parameter selection or repeated fluctuations in subsequent control processes. Based on this, controlling the heating gas to flow into the target area according to the target flow rate and target temperature allows subsequent control to revolve around the parameter state corresponding to the target substitution rate, thereby maintaining the target area under heating conditions that match the target substitution rate. This improves the pertinence, stability, and consistency of subsequent control, avoiding the problem of unclear control state caused by relying solely on experience or temporary adjustments.

[0052] Embodiments of this application also provide an engine device, which is controlled using any engine control method, such as... Figure 2 The engine assembly shown includes:

[0053] The cylinder head 100 has an intake manifold and a water jacket 110. The first gap thickness between the water jacket 110 and the inner wall of the intake manifold in the target area 120 is greater than the second gap thickness between the water jacket and the inner wall of the intake manifold in the non-target area. The target area is the intersection area of ​​the injection axis of the methanol injector and the inner wall of the intake manifold.

[0054] The methanol injector 130 is mounted on the cylinder head 100 and is used to inject methanol into the intake manifold.

[0055] Specifically, a methanol injector is mounted on the cylinder head and injects methanol into the intake manifold. When the methanol injector is operating, methanol enters the intake manifold along the injection direction, forming a corresponding injection trajectory within the intake manifold. The target area is the intersection of the methanol injector's injection axis and the inner wall of the intake manifold, i.e., the location where methanol is more likely to act on the inner wall of the intake manifold during injection.

[0056] In this embodiment, the first gap thickness between the water jacket in the target area and the inner wall of the intake duct is greater than the second gap thickness between the water jacket in the non-target area and the inner wall of the intake duct. That is, the distance between the water jacket and the inner wall of the intake duct is relatively larger in the target area, and relatively smaller in the non-target area. This structural arrangement reduces the cooling effect in the target area, making it easier to maintain a higher temperature there. Since the target area is where methanol is more likely to adhere to the inner wall of the intake duct, increasing the gap thickness in this area helps improve the atomization and vaporization conditions of methanol in that region.

[0057] Furthermore, the cylinder head, water jacket, intake manifold, and methanol injector work together to achieve localized structural optimization in areas prone to methanol adhesion. The methanol injector injects methanol into the intake manifold, which facilitates the flow of methanol and intake air. The water jacket, through variations in the thickness of different sections, creates varying cooling conditions for target and non-target areas. This allows the engine system to not only perform the basic function of injecting methanol into the intake manifold but also to specifically optimize locations prone to methanol adhesion by leveraging structural differences in the target area.

[0058] In one alternative, the thickness of the first gap is 1.3-1.5 times the thickness of the second gap.

[0059] In the above embodiments, by setting the first interval thickness to 1.3-1.5 times the second interval thickness, a clear structural difference can be formed between the target area and the non-target area, so that the cooling effect at the corresponding position of the target area is weakened relative to the non-target area, thereby making it easier for the target area to maintain a higher temperature. Since the target area is the position where methanol is more likely to come into contact with the inner wall of the intake duct after injection, by controlling the first interval thickness within the above multiple range, it can enhance the targeted improvement effect on the methanol adhesion problem in this area, which is conducive to promoting methanol evaporation and vaporization. It can also avoid the problem that the local temperature rise is not obvious due to the interval thickness being too small, or that the structural change is too drastic due to the interval thickness being too large. Thus, the target area achieves a good balance between structural feasibility and local thermal management effect, which is conducive to improving methanol atomization and vaporization conditions and improving the effect of methanol participating in combustion.

[0060] In another alternative, the target area is a circular area with a radius of 10mm-15mm.

[0061] In the above embodiments, the thickness of the gap between the water jacket and the inner wall of the intake duct is increased within this range, so that the cooling effect in this range is weakened compared with other areas, thereby increasing the local temperature of the target area. Since the methanol adhesion problem mainly occurs in the local area where the jet action is more concentrated, limiting the target area to a radius of 10mm-15mm can better cover the main areas of methanol jet impact and adhesion, so that the thickened structure mainly acts on the areas that need to be improved, thereby more specifically reducing methanol adhesion and promoting methanol atomization and vaporization. At the same time, if the range is too small, it may not be able to fully cover the main areas of methanol adhesion, resulting in insufficient local improvement effect. If the range is too large, the thickening range will extend to non-critical areas, reducing the targeting of local control. Therefore, setting the target area to the above range is conducive to achieving a balance between the local structural optimization effect and the overall structural rationality.

[0062] To enable those skilled in the art to better understand the technical solution of this application, the implementation process of the engine control method of this application will be described in detail below with reference to specific embodiments.

[0063] This embodiment relates to a specific engine control method, such as... Figure 3 As shown, it includes the following steps:

[0064] Step S1: Optimize the structure of the methanol-adhesive region and obtain the initial temperature of the target region;

[0065] Specifically, firstly, the wall thickness of the cylinder head water jacket is optimized to create a cooling structure with varying wall thicknesses, allowing for targeted localized cooling adjustments to the intake manifold. Specifically, the localized area where the methanol injector's injection axis intersects with the inner wall of the intake manifold is defined as the target area. This target area can be a circular region with radius R, representing the core region where the methanol jet directly impacts and adheres to the walls most severely. By increasing the water jacket wall thickness corresponding to this target area, the heat exchange area and heat transfer coefficient of the cooling water at that location are reduced, decreasing the cooling intensity. This ensures that the wall temperature of the target area is higher than the surrounding intake manifold wall temperature, thereby suppressing methanol adhesion in this region.

[0066] In some embodiments, based on the original water jacket wall thickness, the initial design value of the wall thickness increment corresponding to the target area can be 30% to 50% of the original wall thickness. For example, if the original wall thickness is 5 mm, the thickened wall thickness can be 6.5 mm to 7.5 mm. The target area preferably adopts a rounded transition thickening structure to avoid stress concentration; the radius R of the circular area can be initially set to 10 mm to 15 mm to cover the core impact area of ​​the methanol jet. After completing the above unequal wall thickness optimization, the initial temperature T0 of the target area is obtained without introducing heating gas. The initial temperature T0 is the temperature of the inner wall of the gas passage in the target area, which can be detected by a temperature sensor pre-embedded in the target area. The initial temperature T0 serves as the reference temperature for subsequent temperature adjustment and control.

[0067] Step S2: Introduce heating gas into the target area at a first flow rate, and obtain the first temperature and the first methanol substitution rate;

[0068] Specifically, the engine is controlled to operate in dual-fuel mode, and heating gas is introduced into the target area. This heating gas can be intake air compressed by a turbocharger, eliminating the need for a separate gas source. The heating gas is introduced from the side of the air passage wall to locally heat the target area. The temperature of the heating gas is higher than the initial temperature T0, thereby increasing the wall temperature of the target area, reducing methanol adhesion to the wall, and promoting methanol evaporation.

[0069] Specifically, heating gas is introduced into the target area at a first flow rate Z1. After a preset time, the first temperature T1 of the target area is obtained, where T1 is greater than T0. Then, the first methanol substitution rate K1 corresponding to the first temperature T1 is obtained.

[0070] In some embodiments, the first flow rate Z1 can be set based on a target area wall temperature increase of 5°C to 10°C, and is preferably 1% to 2% of the total engine intake flow rate. For example, when the total engine intake flow rate is 1000 kg / h, the first flow rate Z1 can be 10 kg / h to 20 kg / h.

[0071] In some embodiments, the target temperature of the target area can be controlled within the range of 80°C to 120°C. This temperature range is conducive to the rapid vaporization of methanol, while avoiding problems such as increased heat load or coking caused by excessively high local temperatures.

[0072] Step S3: If the first methanol substitution rate does not meet the requirements, increase the heating gas flow rate and circulate to obtain the corresponding temperature and methanol substitution rate;

[0073] Specifically, if the first methanol substitution rate K1 does not meet the target requirement, the flow rate of the heating gas is increased to the second flow rate Z2, and after the preset time period, the second temperature T2 and the second methanol substitution rate K2 of the target area are obtained, wherein T2 is greater than T1. If the second methanol substitution rate K2 meets the target requirement, the subsequent steps can proceed; if the second methanol substitution rate K2 still does not meet the target requirement, the flow rate of the heating gas is further increased to Zn, and after the corresponding flow rate is applied, the temperatures T3, T4...Tn of the target area and the corresponding methanol substitution rates K3, K4...Kn are obtained sequentially, wherein Tn is greater than Tn-1.

[0074] In some embodiments, a constant gradient incremental method can be used between two adjacent flow rate adjustments. Specifically, the flow rate ΔZ increased each time can be set to 20% to 50% of the first flow rate Z1. For example, when Z1 is 20 kg / h, ΔZ can be 10 kg / h, then Z2 is 30 kg / h, Z3 is 40 kg / h, and so on. Using a constant gradient incremental method makes the temperature increase process smoother, facilitating subsequent calibration and control.

[0075] During the cyclical increase of the heating gas flow rate, the process of "introducing heating gas at the current flow rate—obtaining the current temperature—obtaining the current methanol substitution rate—determining whether the methanol substitution rate meets the requirements" is repeated. If the current methanol substitution rate meets the target requirement, the corresponding heating gas flow rate and target area temperature are recorded; if the current methanol substitution rate still does not meet the target requirement, it is further determined whether the current temperature has reached the preset upper temperature limit TMAX. If the current temperature is less than TMAX, the heating gas flow rate is further increased; if the current temperature reaches TMAX, the increase in the heating gas flow rate is stopped. In some embodiments, the above target requirement can be a methanol substitution rate of 90%.

[0076] Step S4: Analyze multiple temperatures and their corresponding methanol substitution rates to determine the target flow rate and target temperature corresponding to the optimal methanol substitution rate;

[0077] Specifically, after obtaining multiple temperatures within the temperature range of T1 to Tn and the corresponding multiple methanol substitution rates K1 to Kn, the correspondence between the multiple temperatures and the multiple methanol substitution rates is sorted out and compared to determine the optimal methanol substitution rate.

[0078] For example, in some embodiments, if the methanol substitution rate Kn-1 corresponding to Tn-1 is determined to be the optimal methanol substitution rate within the range of T1 to Tn, then Zn-1 is determined as the target flow rate and Tn-1 is determined as the target temperature. In this case, it can be considered that when the heating gas flow rate is Zn-1 and the target area temperature is Tn-1, the atomization and vaporization effect of methanol is better, and the methanol substitution effect is optimal.

[0079] Furthermore, if the temperature continues to rise but the methanol substitution rate no longer increases, or the methanol substitution rate is lower than the methanol substitution rate corresponding to the previous temperature point, then the previous temperature point and its corresponding flow rate can be used as the target temperature and target flow rate for subsequent control.

[0080] Step S5: Control based on the determined target flow rate and target temperature;

[0081] After determining the target flow rate and target temperature, the heating gas is then introduced into the target area according to these parameters during subsequent control, maintaining the target area at a temperature conducive to methanol atomization and vaporization. This reduces methanol adhesion to the intake manifold wall, increases methanol vaporization rate, and allows more methanol to enter the combustion chamber with the air for combustion, thereby improving the engine's methanol substitution rate.

[0082] Therefore, by combining the above-mentioned structural optimization with the control process, a more suitable local thermal environment for methanol evaporation can be formed in the target area. By screening the relationship between flow rate adjustment and temperature and methanol substitution rate, optimal control parameters can be determined, thereby improving methanol utilization and the operating performance of the dual-fuel engine.

[0083] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0084] This invention provides an engine control system, including a processor, a memory, and a program stored in the memory and executable on the processor. When the processor executes the program, it performs at least the following steps: Step S101, controlling the engine to operate in a dual-fuel mode and controlling the heating gas to be introduced into a target area at a first flow rate. The target area is the intersection area of ​​the injection axis of the methanol injector and the inner wall of the intake manifold. The dual-fuel mode is an operating mode in which methanol and diesel participate in combustion together.

[0085] Specifically, by activating the engine to the appropriate operating state and applying heating to the target area, targeted thermal regulation can be performed on the methanol-adhesive wall areas during engine operation. Since this location is where methanol is more likely to form adhesion and a liquid film after injection, localized heating of this area helps to weaken the methanol's tendency to adhere to the wall, improves methanol evaporation conditions, and thus creates conditions for subsequently increasing the proportion of methanol participating in combustion.

[0086] Step S102: After a preset time, obtain the first temperature of the target area and obtain the first methanol substitution rate. The heating gas is the gas after the engine intake is compressed.

[0087] Specifically, the first temperature is used to reflect the current local heating state, and the methanol substitution rate is used to reflect the actual effect of methanol participating in combustion.

[0088] Step S103: When the first methanol substitution rate is greater than or equal to the preset substitution rate, the heating gas is controlled to be introduced into the target area at the first flow rate.

[0089] Specifically, when the first methanol substitution rate reaches the preset substitution rate, it indicates that the current heating conditions are sufficient to meet the requirements for methanol substitution effect, so the current flow rate can be maintained for control.

[0090] Step S104: When the first methanol substitution rate is less than the preset substitution rate and the first temperature is less than the preset temperature, the heating gas is controlled to be introduced into the target area at a second flow rate, and after the preset time, the second temperature of the target area is obtained, and the second methanol substitution rate is obtained, wherein the second flow rate is greater than the first flow rate.

[0091] Specifically, when the first methanol substitution rate has not yet reached the preset substitution rate, and the current temperature is still below the preset temperature, it indicates that the existing heating intensity is insufficient, but there is still room to further improve the local thermal conditions. In this case, by increasing the heating gas flow rate and obtaining the second temperature and the second methanol substitution rate again, the control results after increasing the flow rate are reassessed. By comparing the methanol substitution effect after increasing the flow rate, it can be determined whether the expected control objective has been achieved after increasing the flow rate.

[0092] Step S105: When the second methanol substitution rate is greater than or equal to the preset substitution rate, the heating gas is controlled to be introduced into the target area at the second flow rate.

[0093] Specifically, when the second methanol substitution rate reaches the preset substitution rate, it indicates that the increased heating flow rate can meet the requirements for methanol substitution effect.

[0094] The devices mentioned in this article can be servers, PCs, tablets, mobile phones, etc.

[0095] Optionally, obtaining the first methanol substitution rate includes: controlling the engine to operate in pure diesel mode under preset operating conditions, and obtaining the first diesel consumption within a preset time period; controlling the engine to operate in dual-fuel mode under the preset operating conditions, and obtaining the second diesel consumption within the preset time period after the heating gas is introduced into the target area at the first flow rate for the preset duration; and determining the first methanol substitution rate based on the first diesel consumption and the second diesel consumption.

[0096] Optionally, determining the first methanol substitution rate based on the first diesel consumption and the second diesel consumption includes: determining the difference between the first diesel consumption and the second diesel consumption; and determining the first methanol substitution rate as the quotient of the difference and the first diesel consumption.

[0097] Optionally, after obtaining the first temperature of the target area and the first methanol substitution rate after a preset time, the method further includes: when the first temperature is greater than the preset temperature and the first methanol substitution rate is less than the preset substitution rate, controlling the heating gas to be introduced into the target area at the first flow rate.

[0098] Optionally, the above method further includes: when the temperature of the target area is greater than or equal to the preset temperature and the methanol substitution rate is less than the preset substitution rate, outputting an alarm message to indicate that the temperature of the target area is greater than or equal to the preset temperature and the methanol substitution rate has not reached the preset substitution rate.

[0099] Optionally, the above method further includes: when the methanol substitution rate is greater than or equal to the target substitution rate, determining the flow rate of the heating gas corresponding to the target substitution rate as the target flow rate, wherein the target substitution rate is greater than the preset substitution rate; determining the temperature of the target area corresponding to the target substitution rate as the target temperature, and controlling the heating gas to be introduced into the target area according to the target flow rate and the target temperature.

[0100] It is obvious to those skilled in the art that the modules or steps of the present invention described above can be implemented using general-purpose computing devices. They can be centralized on a single computing device or distributed across a network of multiple computing devices. They can be implemented using computer-executable program code, and thus can be stored in a storage device for execution by a computing device. In some cases, the steps shown or described can be performed in a different order than those described herein, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Thus, the present invention is not limited to any particular combination of hardware and software.

[0101] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0102] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0103] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0104] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0105] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0106] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0107] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information by any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0108] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0109] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0110] As can be seen from the above description, the embodiments of this application achieve the following technical effects:

[0111] The engine control method of this application controls the engine to operate in dual-fuel mode and introduces heated gas into the target area of ​​the intake manifold inner wall through the injection axis of the methanol injector. This increases the local temperature of the area where methanol easily adheres to the wall, reduces methanol adhesion and liquid film formation on the intake manifold inner wall, promotes methanol atomization and vaporization, and allows more methanol to enter the combustion chamber with the intake air to participate in combustion. Simultaneously, by obtaining the target area temperature at different flow rates and determining the corresponding methanol substitution rate, a more suitable heating gas flow rate can be gradually matched. While ensuring that the target area temperature does not exceed the preset temperature, the methanol substitution rate is increased, thereby improving the methanol utilization effect and combustion stability of the dual-fuel engine. This solves the problem that in existing methanol injectors, methanol easily adheres to the inner wall of the intake manifold, resulting in poor atomization and vaporization effects and a low methanol substitution rate.

[0112] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for controlling an engine, characterized in that, include: The engine is controlled to operate in a dual-fuel mode, and the heated gas is controlled to be introduced into the target area at a first flow rate. The target area is the intersection of the injection axis of the methanol injector and the inner wall of the intake manifold. The dual-fuel mode is an operating mode in which methanol and diesel participate in combustion together. After a preset time period, the first temperature of the target area is obtained, and the first methanol substitution rate is obtained. The heating gas is the gas compressed after the engine intake. When the first methanol substitution rate is greater than or equal to the preset substitution rate, the heating gas is controlled to be introduced into the target area at the first flow rate; When the first methanol substitution rate is less than the preset substitution rate and the first temperature is less than the preset temperature, the heating gas is controlled to be introduced into the target area at a second flow rate, and after the preset time, the second temperature of the target area is obtained, and the second methanol substitution rate is obtained, wherein the second flow rate is greater than the first flow rate. When the second methanol substitution rate is greater than or equal to the preset substitution rate, the heating gas is controlled to be introduced into the target area at the second flow rate.

2. The control method according to claim 1, characterized in that, To obtain the first methanol substitution rate, including: The engine is controlled to operate in pure diesel mode under preset operating conditions, and the first diesel consumption within a preset time period is obtained. The engine is controlled to operate in the dual-fuel mode under the preset operating conditions, and after the heating gas is introduced into the target area at the first flow rate for the preset time period, the second diesel consumption within the preset time period is obtained. The first methanol substitution rate is determined based on the first diesel consumption and the second diesel consumption.

3. The control method according to claim 2, characterized in that, Determining the first methanol substitution rate based on the first diesel consumption and the second diesel consumption includes: Determine the difference between the first diesel consumption and the second diesel consumption; The first methanol substitution rate is determined to be the quotient of the difference and the first diesel consumption.

4. The control method according to claim 1, characterized in that, After obtaining the first temperature of the target area after a preset time period and obtaining the first methanol substitution rate, the method further includes: When the first temperature is greater than the preset temperature and the first methanol substitution rate is less than the preset substitution rate, the heating gas is controlled to be introduced into the target area at the first flow rate.

5. The control method according to claim 1, characterized in that, The method further includes: If the temperature in the target area is greater than or equal to the preset temperature and the methanol substitution rate is less than the preset substitution rate, an alarm message is output to indicate that the temperature in the target area is greater than or equal to the preset temperature and the methanol substitution rate has not reached the preset substitution rate.

6. The control method according to claim 1, characterized in that, The method further includes: When the methanol substitution rate is greater than or equal to the target substitution rate, the flow rate of the heating gas corresponding to the target substitution rate is determined as the target flow rate, and the target substitution rate is greater than the preset substitution rate; The temperature of the target area corresponding to the target substitution rate is determined as the target temperature, and the heating gas is controlled to be introduced into the target area according to the target flow rate and the target temperature.

7. An engine device, wherein the engine device is controlled by the engine control method according to any one of claims 1 to 6, characterized in that, include: The cylinder head has an intake manifold and a water jacket. The first gap thickness between the water jacket and the inner wall of the intake manifold in the target area is greater than the second gap thickness between the water jacket and the inner wall of the intake manifold in the non-target area. The target area is the intersection area of ​​the injection axis of the methanol injector and the inner wall of the intake manifold. The methanol injector is mounted on the cylinder head and is used to inject methanol into the intake manifold.

8. The engine device according to claim 7, characterized in that, The thickness of the first gap is 1.3-1.5 times the thickness of the second gap.

9. The engine device according to claim 7, characterized in that, The target area is a circular area with a radius of 10mm-15mm.

10. A control system for an engine, characterized in that, include: One or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the one or more programs comprising methods for performing any one of claims 1 to 6.

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