Methanol fuel engine fuel supply pipe system with heating function

Abstract

The utility model discloses a methanol fuel engine fuel supply pipe system with a heating function, which comprises a plurality of three-layer pipes, a plurality of adapting blocks and a plurality of limiting plates, each three-layer pipe comprises an inner pipe, a middle pipe, an outer pipe and two arc-shaped PTC (Positive Temperature Coefficient) heating plates, the two arc-shaped PTC heating plates are respectively embedded into a peripheral ring groove of the inner pipe, and the middle pipe is inserted into the outer pipe and is fixedly connected with the outer pipe into a whole. An outer pipe annular cavity serving as a nitrogen channel is formed between an inner hole of the outer pipe and the peripheral face of the middle pipe, a center hole of the adapter block is communicated with the inner pipe to serve as a methanol fuel channel, and the two ends of the three-layer pipe are inserted into a pipe system which is fixedly connected through the adapter block and the limiting plate to form an integral structure. According to the methanol fuel engine, the manufacturing cost of the engine is remarkably reduced, methanol fuel in the inner pipe is heated after the arc-shaped PTC heating plate is electrified, the low-temperature cold start performance of the methanol fuel engine is effectively improved, and the safety performance of the methanol fuel engine and the purging efficiency of the methanol fuel are comprehensively improved.

Description

Technical Field

[0001] This utility model relates to a fuel supply system for a new energy engine, and more particularly to a fuel supply pipeline system for a methanol fuel engine that can heat methanol fuel, belonging to the field of new energy engine technology. Background Technology

[0002] Methanol fuel, with its advantages of being clean, environmentally friendly, and widely available, has shown great application potential in the field of new energy engines. However, its high latent heat of vaporization has brought many challenging problems to its practical application in engines.

[0003] In terms of cold starts at low temperatures, methanol fuel faces significant challenges regardless of whether it's direct injection or port injection. During a cold start, the methanol fuel injected into the engine intake manifold often exhibits poor vaporization, entering the cylinder in liquid form. This not only dilutes the lubricating oil, affecting the engine's lubrication system, but also lowers the cylinder temperature under low to medium loads, causing the flame front to quench on the cylinder walls, leading to incomplete combustion. This results in decreased engine performance and increased emissions from methanol fuel engines.

[0004] Meanwhile, the toxicity of methanol fuel cannot be ignored; it is extremely harmful to the human nervous and circulatory systems. If a new fuel engine leaks methanol during operation, it could potentially cause serious safety accidents, threatening human life and health as well as the safety of the surrounding environment. Even in unburned form, methanol vapor evaporation or accidental splashes onto the skin can cause significant harm. To address the problem of cold starts in methanol fuel engines, existing improvements mainly fall into two categories: one is to use an external auxiliary fuel tank and add a fuel injection system for ignition. This improvement is costly, makes the engine structure more complex, and increases the difficulty of later maintenance; the other is to preheat the methanol fuel, mostly through an external heater before it enters the engine. This improvement not only requires an additional preheating system, increasing engine manufacturing costs, but also has low heating efficiency, and due to the toxicity of methanol fuel, the consequences of a leak would be unimaginable. Regarding methanol leaks, existing improvements involve installing an inert gas purging layer in the engine fuel supply line to inertize and purge leaked methanol in a timely manner. However, this improvement has low purging efficiency and cannot meet the requirements of high efficiency and safety.

[0005] Furthermore, the flowability of methanol fuel within the fuel supply pipeline is significantly affected by temperature. At lower temperatures, the viscosity of methanol fuel increases, and its flowability decreases, potentially leading to incomplete purging. By increasing the pipeline temperature (typically between 20°C and 40°C), good flowability of methanol fuel can be maintained, and nitrogen purging efficiency can be improved, ensuring that residual methanol and impurities within the pipeline are thoroughly removed.

[0006] How to effectively improve the low-temperature cold start performance of methanol fuel engines, significantly reduce the risk of fuel splashing and leakage, and comprehensively improve the safety performance and methanol fuel purging efficiency of methanol fuel engines has become a key technical problem that needs to be solved by those skilled in the art. Utility Model Content

[0007] The purpose of this invention is to provide a fuel supply system for a methanol fuel engine with a heating function, which effectively improves the low-temperature cold start performance of the methanol fuel engine.

[0008] This utility model is achieved through the following technical solution:

[0009] A fuel supply piping system for a methanol fuel engine with heating function includes several three-layer pipes, adapter blocks for connecting the three-layer pipes, and limiting plates fixed at both ends of the adapter blocks. Each three-layer pipe includes an inner pipe, a middle pipe, an outer pipe, and two arc-shaped PTC heating plates. The inner pipe is a pipe with stepped flanges at both ends and an annular groove recessed in the middle. The two arc-shaped PTC heating plates are respectively embedded in the annular groove. The radial end faces of the arc-shaped PTC heating plates are limited by axial limiting strips symmetrically arranged on the outer circumference of the inner pipe. The inner pipe is inserted into the middle pipe. The stepped flanges at both ends of the inner pipe are threaded to the two ends of the inner hole of the middle pipe and are coated with sealant. An annular cavity with closed ends is provided between the outer circumference of the arc-shaped PTC heating plates and the inner hole of the middle pipe. Two pairs of outwardly extending protrusions are arranged radially at intervals on the upper and lower sides of the outer circumference of the middle pipe. The middle tube is inserted into the outer tube and sealed by the O-ring of the outer protrusion embedded in the top surface of the outer protrusion. The two ends of the outer tube are respectively provided with outer tube flanges. The connecting screws pass through the outer tube and are screwed into the corresponding outer protrusions to fix the outer tube and the middle tube into a whole. An outer tube annular cavity, which serves as a nitrogen channel, is provided between the inner hole of the outer tube and the outer circumferential surface of the middle tube. The two ends of the three-layer tube are respectively inserted into one end of the corresponding adapter block. The limiting plates are respectively positioned on the end of the outer tube and fixed on the vertical end face of the corresponding adapter block, thereby fixing several three-layer tubes into a whole pipe system through the adapter block and the limiting plate. The methanol injector oil pipe joint is fixed on the adapter block. The central hole of the adapter block is connected to the inner tube, which serves as the methanol fuel channel. The adapter blocks at both ends of the fuel supply pipe system are connected to the methanol station and the nitrogen station respectively through the corresponding double-walled pipes.

[0010] The objective of this utility model can also be further achieved through the following technical measures.

[0011] Furthermore, the adapter block is a cube. At the center of the vertical end faces at both ends of the adapter block, there are annular grooves with an inner diameter larger than the central hole of the adapter block. Positioning tubes extend outward from the central axis of each annular groove, with an inner diameter larger than the central hole diameter of the adapter block. At the center of the two apex inclined surfaces of the adapter block, there are threaded holes for the injector oil pipe connector and a pressure regulator valve, respectively. The inner ends of the threaded holes for the injector oil pipe connector and the pressure regulator valve intersect perpendicularly with the central hole of the adapter block. Multiple transverse holes are distributed on the bottom surface of the annular grooves, with both ends of each transverse hole penetrating the bottom surface of the annular groove and the outer surface of the outer surface. The tube has an annular cavity. When the two ends of the adapter block are connected to the corresponding ends of the three-layer tubes, the positioning round tubes are embedded in the annular grooves of the stepped flange end faces of the corresponding inner tube ends. The ends of the outer tube, middle tube, and inner tube abut against the bottom surface of the corresponding annular groove, so that the two ends of the three-layer tubes are positioned in the corresponding vertical end faces of the adapter block. The two ends of the multiple transverse holes are connected to the annular cavity of the outer tube of the three-layer tubes, and the central hole of the adapter block is connected to the inner tube. The ends of the outer tubes are inserted into the annular grooves, and the limiting plates are fixed on the corresponding vertical end faces of the adapter block, thereby fixing the three-layer tubes into an integral structure through the adapter block.

[0012] Furthermore, the limiting plate is formed by joining two half limiting plates together. The adjacent sides of the half limiting plates are respectively provided with semi-circular notches matching the circumference of the outer tube flange. The semi-circular notches are radially provided with semi-circular positioning grooves, and the outer tube flange is respectively provided with radially extending positioning ring ribs. When the two half limiting plates are positioned on the outer tube flange, the positioning ring ribs are respectively embedded in the corresponding semi-circular positioning grooves, the semi-circular notches abut against the outer circumference of the outer tube flange, and the fastening screws pass through the four corners of the limiting plate formed by splicing the two half limiting plates and are screwed into the vertical end face of the corresponding adapter block, thereby fixing the two ends of multiple three-layer pipes together into a pipe system with an integral structure through the adapter block and the limiting plate respectively.

[0013] Furthermore, the power cord at the end of the arc-shaped PTC heating plate passes through one end of the annular cavity of the middle tube and then leads to the outside of the outer tube through a connecting pipe; the inner end of the connecting pipe passes through the outer tube and the middle tube in sequence and is welded to the outer tube; the inside of the connecting pipe is sealed with sealant, and the outer end of the connecting pipe is sealed with a screw cap; the power cord is led out from the center hole of the screw cap.

[0014] Furthermore, two inner tube radial O-rings are installed in the annular groove on the stepped flange end face, and the positioning round tubes are respectively inserted into the annular grooves on the stepped flange end face of the corresponding inner tube end; the stepped flange end face is equipped with an inner tube axial O-ring, and the outer tube end is equipped with an outer tube radial O-ring.

[0015] This invention employs a three-layered pipe system—inner, middle, and outer pipes—assembled as a fuel supply pipe for a methanol fuel engine. Two arc-shaped PTC heating plates are embedded in the annular groove in the middle of the inner pipe. When energized, the arc-shaped PTC heating plates instantly heat the methanol fuel in the inner pipe to 40°C within 3 seconds, eliminating the need for an external auxiliary fuel tank, an additional fuel injection system for ignition, or an external heater to preheat the methanol fuel before it is introduced into the engine. The design is compact, highly reliable, and significantly reduces the manufacturing cost of the methanol fuel engine. By using the arc-shaped PTC heating plates to heat the methanol fuel in the inner pipe, the low-temperature cold-start performance of the methanol fuel engine is effectively improved, comprehensively enhancing its safety performance and methanol fuel purging efficiency.

[0016] The advantages and features of this utility model will be illustrated and explained through the following non-limiting description of preferred embodiments, which are given by way of example only with reference to the accompanying drawings. Attached Figure Description

[0017] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0018] Figure 2 This is the front view of this utility model;

[0019] Figure 3 yes Figure 2 AA enlarged sectional view;

[0020] Figure 4 This is a magnified 3D view of the adapter block;

[0021] Figure 5 yes Figure 3 BB section view;

[0022] Figure 6 yes Figure 4 The C-direction view;

[0023] Figure 7 yes Figure 6 DD sectional view;

[0024] Figure 8 This is the front view of the limit plate;

[0025] Figure 9 yes Figure 2 Enlarged cross-sectional view of the EE. Detailed Implementation

[0026] The present invention will be further described below with reference to the accompanying drawings and embodiments of a methanol-fueled 6-cylinder engine.

[0027] like Figures 1-9As shown, this embodiment includes five three-layer tubes 1, adapter blocks 2 for connecting the three-layer tubes 1, and limiting plates 3 fixed at both ends of the adapter blocks. The three-layer tubes 1 include an inner tube 11, a middle tube 12, an outer tube 13, and two arc-shaped PTC heating plates 14. The inner tube 11 is a tube with stepped flanges 111 at both ends and an annular groove 112 recessed in the middle. The two arc-shaped PTC heating plates 14 are respectively embedded in the annular groove 112. The radial end faces of the arc-shaped PTC heating plates 14 are respectively limited by axial limiting strips 114 symmetrically arranged on the outer circumferential surface of the inner tube 11. The inner tube 11 is inserted into the middle tube 12. The stepped flanges 111 at both ends of the inner tube are threaded to the two ends of the inner hole of the middle tube 12 and are coated with sealant. An annular cavity 121 with closed ends is provided between the outer circumferential surface of the arc-shaped PTC heating plate 14 and the inner hole of the middle tube 12. The arc-shaped PTC heating plate, once energized, instantly heated the methanol fuel in the inner tube to 40°C within 3 seconds.

[0028] like Figure 3 As shown, two pairs of outwardly extending protrusions 122 are arranged radially and spaced apart on the outer circumferential surface of the middle tube 12. The middle tube 12 is inserted into the outer tube 13 and sealed by an O-ring 123 embedded in the top surface of the protrusions 122. The two ends of the outer tube 13 are respectively provided with outer tube flanges 131. Connecting screws 4 are screwed into the corresponding protrusions 122 through the outer tube 13, thus fixing the outer tube 13 and the middle tube 12 together. An annular cavity 132, serving as a nitrogen gas passage, is provided between the inner hole of the outer tube 13 and the outer circumferential surface of the middle tube 14.

[0029] like Figures 4-7As shown, the adapter block 2 is a cube. At the center of the vertical end faces at both ends of the adapter block, there are annular grooves 22 with an inner diameter larger than the diameter of the central hole 21 of the adapter block. Positioning tubes 221 extend outward from the center axis of the annular grooves 22, and the inner diameter of the positioning tubes 221 is larger than the diameter of the central hole 21 of the adapter block. At the center of the two apex inclined surfaces of the adapter block 2, there are threaded holes 23 for the methanol injector oil pipe connector and threaded holes 24 for the pressure regulator valve. The inner ends of the threaded holes 23 and 24 intersect perpendicularly with the central hole 21 of the adapter block. One end of the pressure regulator valve is screwed onto the threaded hole 24. When the methanol fuel engine experiences pressure fluctuations due to load changes, the pressure regulator valve can stabilize the pressure fluctuations in the inner tube 11. Multiple transverse holes 222 are distributed on the bottom surface of the annular grooves 22, with both ends of the transverse holes 222 penetrating the bottom surface of the annular grooves 22 and the annular cavity 132 of the outer tube, respectively. When the two ends of the adapter block 2 are connected to the corresponding ends of the three-layer pipe, the positioning round tubes 221 are respectively embedded in the stepped flange annular grooves 113 on the end face of the stepped flange 111 of the corresponding inner tube 11. The ends of the outer tube 13, the middle tube 12, and the inner tube 11 respectively abut against the bottom surface of the corresponding annular grooves 22, so that the two ends of the three-layer pipe are respectively positioned in the vertical end faces of the adapter block 2. Since the two ends of the multiple transverse holes 222 are respectively connected to the annular cavity 132 of the outer tube of the three-layer pipe, an outer nitrogen channel is provided for the three-layer pipe. The central hole 21 of the adapter block is connected to the inner tube 11, providing a central methanol fuel channel for the three-layer pipe.

[0030] like Figure 3 and Figure 8 As shown, the limiting plate 3 is formed by joining two half-limiting plates 31 together. The adjacent sides of the half-limiting plates 31 are respectively provided with semi-circular notches 311 that match the circumference of the outer tube flange 131. The semi-circular notches 311 are radially provided with semi-circular positioning grooves 312. The outer tube flange 131 is respectively provided with radially extending positioning ring ribs 133. When the two half-limiting plates 31 are positioned on the outer tube flange 131, the positioning ring ribs 133 are respectively embedded in the corresponding semi-circular positioning grooves 312, and the semi-circular notches 311 abut against the outer circumference of the outer tube flange 131. The fastening screws 5 pass through the four corners of the limiting plate 3 formed by splicing the two half-limiting plates 31 and are screwed into the vertical end face of the corresponding adapter block 2, thereby fixing multiple three-layer pipes into a pipe system with an integral structure through the adapter block 2 and the limiting plate 3 respectively.

[0031] The methanol injector oil pipe connector 6 is fixed on the adapter block 2. The central hole 21 of the adapter block is connected to the inner pipe 11, which serves as the methanol fuel passage. The adapter blocks 2 at both ends of the fuel supply pipeline connected to the methanol injector oil pipe connector 6 are respectively connected to the methanol station and the nitrogen station through corresponding double-walled pipes. The methanol injector oil pipe connector 6 leads to the methanol injectors of each cylinder of the methanol fuel engine through the methanol injector oil pipe, injecting methanol fuel into each cylinder for combustion and power generation, ensuring the normal operation of the methanol fuel engine.

[0032] like Figure 2 , Figure 3 and Figure 9 As shown, the power cord 124 at the end of the arc-shaped PTC heating plate 14 passes through the left end of the annular cavity 132 of the middle tube and then leads to the outside of the outer tube 13 through the connecting pipe 7; the inner end of the connecting pipe 7 passes through the outer tube 13 and the middle tube 12 in sequence and is welded to the outer tube 13 respectively; the inside of the connecting pipe 7 is sealed with sealant 71; the outer end of the connecting pipe 7 is sealed with a screw cap 72; and the power cord 124 is led out from the center hole of the screw cap 72.

[0033] like Figure 3 As shown, two radial O-rings 114 are installed in the stepped flange annular groove 113 on the end face of the stepped flange 111, and an axial O-ring 115 is installed on the end face of the stepped flange 111, effectively preventing nitrogen gas from entering the inner tube 11 from the annular cavity 132 of the middle tube. An outer radial O-ring 134 is installed at the end of the outer tube to seal the methanol fuel in the inner tube 11, preventing leakage and ensuring the safe use of this invention.

[0034] In addition to the above embodiments, the present invention may have other implementation methods. All technical solutions formed by equivalent substitution or equivalent transformation fall within the protection scope claimed by the present invention.

Claims

1. A fuel supply system for a methanol fuel engine having a heating function, characterized by: The three-layer pipe comprises an inner pipe, a middle pipe, an outer pipe and two arc-shaped PTC heating plates, the inner pipe is a pipe with stepped flanges at both ends and a recessed ring groove in the middle, the two arc-shaped PTC heating plates are embedded in the ring grooves, and the radial end faces of the arc-shaped PTC heating plates are limited by the axial limiting strips symmetrically arranged on the outer circumferential surface of the inner pipe; the inner pipe is inserted into the middle pipe, the stepped flanges at both ends of the inner pipe are threadedly connected with the inner holes at both ends of the middle pipe, and are coated with sealing glue; the outer circumferential surface of the arc-shaped PTC heating plate is provided with a middle pipe annular cavity with closed ends between the outer circumferential surface of the arc-shaped PTC heating plate and the inner hole of the middle pipe; the outer circumferential surface of the middle pipe is provided with two pairs of outwardly extending outer protruding seats arranged on the upper and lower sides in the radial direction; the middle pipe is inserted into the outer pipe and is sealed by the outer protruding seat O-shaped sealing ring embedded in the top surface of the outer protruding seat; the outer pipe is provided with outer pipe flanges at both ends; connecting screws are respectively inserted into the corresponding outer protruding seats through the outer pipe, so as to fixedly connect the outer pipe and the middle pipe into an integrated structure; the outer pipe annular cavity between the inner hole of the outer pipe and the outer circumferential surface of the middle pipe is used as a nitrogen passage; the two ends of the three-layer pipe are respectively inserted into one end of the corresponding adapter block, the limiting plates are respectively positioned on the end heads of the outer pipes and are respectively fixed on the vertical end surfaces of the corresponding adapter blocks, so that the plurality of three-layer pipes are fixedly connected into an integrated structure of the pipe system through the adapter blocks and the limiting plates; the alcohol sprayer oil pipe joints are fixed on the adapter blocks, and the central holes of the adapter blocks are connected with the inner pipes as methanol fuel passages; the adapter blocks at both ends of the fuel supply pipe system are connected with the methanol station and the nitrogen station through the corresponding double-wall pipes.

2. The methanol fuel engine fuel supply system having a heating function according to claim 1, characterized by: The adapter block is a cube, the vertical end surfaces at both longitudinal ends of the adapter block are respectively provided with annular grooves with a larger inner diameter than the central hole of the adapter block, the central axes of the annular grooves respectively extend outwardly to form positioning circular pipes, and the inner diameters of the positioning circular pipes are larger than the diameter of the central hole of the adapter block; the central parts of the two top corner bevels of the adapter block are respectively provided with an alcohol sprayer oil pipe joint threaded hole and a pressure stabilizing valve threaded hole, the inner ends of the alcohol sprayer oil pipe joint threaded hole and the pressure stabilizing valve threaded hole are respectively perpendicular to the central hole of the adapter block; a plurality of horizontal holes are distributed on the bottom surface of the annular groove, and the two ends of each horizontal hole respectively penetrate the bottom surface of the annular groove and the outer pipe annular cavity; when the two axial ends of the adapter block are respectively connected with the end heads of the corresponding three-layer pipes, the positioning circular pipes are respectively embedded in the stepped flange ring grooves in the stepped flange end faces of the corresponding inner pipe end heads, and the end heads of the outer pipe, the middle pipe and the inner pipe are respectively abutted on the corresponding bottom surfaces of the annular grooves, so that the two ends of the three-layer pipe are respectively positioned in the corresponding vertical end surfaces of the adapter block, the two ends of each horizontal hole are respectively communicated with the outer pipe annular cavities of the three-layer pipes, and the central hole of the adapter block is communicated with the inner pipe; the end heads of the outer pipes are respectively inserted into the annular grooves, and the limiting plates are respectively fixed on the vertical end surfaces of the corresponding adapter blocks, so that the three-layer pipes are fixedly connected into an integrated structure through the adapter blocks.

3. The methanol fuel engine fuel supply system having a heating function according to claim 1, characterized by: The limiting plate is formed by butt joint of two half limiting plates, adjacent sides of the half limiting plate are respectively provided with semicircular notches matched with outer tube flange peripheral surface, the semicircular notches are radially provided with semicircular positioning grooves, and the outer tube flange is respectively provided with radially extended positioning ring ribs; when the two half limiting plates are positioned on the outer tube flange, the positioning ring ribs are respectively embedded in the corresponding semicircular positioning grooves, the semicircular notches abut on the peripheral surface of the outer tube flange, and the fastening screws are respectively passed through the four corners of the limiting plate spliced by the two half limiting plates and are screwed into the corresponding adapter block vertical end surface, so that the multiple three-layer pipes are respectively fixed and connected into an integral structure pipe system by the adapter blocks and the limiting plates.

4. The methanol fuel engine fuel supply system having a heating function according to claim 1, characterized by: The power line of the arc-shaped PTC heating plate end passes through one end of the middle tube annular cavity, and then is introduced to the outside of the outer tube through the wiring tube; the inner end of the wiring tube successively transversely passes through the outer tube and the middle tube, and is welded with the outer tube, the inner end of the wiring tube is sealed with sealing glue, the outer end of the wiring tube is closed with a screw cap, and the power line is introduced from the screw cap center hole.

5. The methanol fuel engine fuel supply system having a heating function according to claim 2, characterized by: Two inner tube radial O-shaped sealing rings are arranged in the ring groove of the stepped flange end face, and the positioning circular tube is respectively inserted into the ring groove of the stepped flange end face of the corresponding inner tube end; the stepped flange end face is provided with an inner tube axial O-shaped sealing ring, and the outer tube end is provided with an outer tube radial O-shaped sealing ring.

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