Piston and gaseous fuel engine
By setting a pit on the top surface of the piston, the friction of the airflow is reduced and the airflow is guided, the problem of large loss of gas kinetic energy in the engine cylinder is solved, and the thermal efficiency of the gas fuel engine is improved.
Patent Information
- Application Number
- CN202420077564.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-12
- Publication Date
- 2025-01-17
- Estimated Expiration
- 2034-01-12
AI Technical Summary
The kinetic energy loss of the gas in the engine cylinder is too large, which affects the full combustion of gas fuel, resulting in low engine thermal efficiency.
A piston is designed, with the top surface including an outer peripheral flow extrusion area and a central depression area, and a pit is provided to reduce the friction force of the airflow and guide the airflow, maintain the rolling flow energy, and reduce the damage effect of the outer peripheral flow extrusion area on the rolling flow.
By reducing the friction force of the airflow and maintaining the rolling flow energy, the full combustion of the gas fuel is promoted and the thermal efficiency of the gas fuel engine is improved.
Smart Images
Figure CN222363066U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of engine pistons, in particular to a piston and a gas fuel engine using the piston. Background Art
[0002] During engine operation, the intake valve inputs gas fuel into the cylinder body, and the cylinder body cooperates with the top cylinder head to form a large-scale macroscopic tumble flow in the cylinder. When the intake valve is closed, the engine enters the compression stroke, the piston gradually approaches the cylinder head, the cylinder volume gradually decreases, and the gas flow in the cylinder begins to weaken, but the temperature and pressure of the gas in the cylinder gradually increase, the density increases, the friction loss of the gas when it flows over the piston surface increases, and the kinetic energy loss is too much, which is not conducive to full combustion and is not conducive to improving the thermal efficiency of the engine.
[0003] Therefore, how to reduce the kinetic energy loss of the gas in the engine cylinder to promote the complete combustion of the gas fuel in the cylinder and improve the thermal efficiency of the engine is an urgent problem to be solved by technical personnel in this field. Utility Model Content
[0004] In view of this, the utility model provides a piston, wherein a pit is provided in the middle recessed area of the top surface of the piston body, and a flow dead zone is formed at the pit, so that the airflow contacts the dead zone airflow at the pit during the tumbling process, rather than contacting the surface of the pit, thereby reducing the friction force on the airflow and reducing the kinetic energy loss of the airflow. At the same time, the pits provided in the peripheral squeeze flow area can guide the airflow and reduce the destructive effect of the peripheral squeeze flow area on the tumbling flow in the cylinder. The simultaneous action of the pits in the middle recessed area and the peripheral squeeze flow area can better maintain the tumbling flow of the airflow in the cylinder, which is beneficial to the full combustion of the fuel and is beneficial to improving the thermal efficiency of the gas fuel engine. The utility model also provides a gas fuel engine using the above piston, which has higher thermal efficiency.
[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:
[0006] A piston comprises a piston body, wherein the top surface of the piston body comprises an outer peripheral squeeze flow area and a middle recessed area; the outer peripheral squeeze flow area and the middle recessed area are respectively provided with pits.
[0007] Optionally, in the above piston, the peripheral squeeze flow area includes:
[0008] a first region, the first region being proximate to an intake side of an engine block;
[0009] a second region, the second region being proximate to an exhaust side of the engine block;
[0010] A third region, the third region being sandwiched between the first and second regions;
[0011] The fourth area is sandwiched between the first area and the second area; the first area, the second area, the third area and the fourth area are all provided with pits.
[0012] Optionally, in the above piston, the recess is oval;
[0013] The long axes of the pits in the first region are arranged along a first direction; the first direction is a straight line direction from the air intake side to the exhaust side; or
[0014] Among all the pits in the first area, a pit located in the middle along the second direction is a central pit, and its long axis is arranged along the first direction; the long axes of other pits in the first area gradually approach the central pit from the end away from the exhaust side to the end close to the exhaust side; the second direction is perpendicular to the first direction.
[0015] Optionally, in the above piston, the major axis of the pit in the middle recessed area is arranged along the second direction.
[0016] Optionally, in the above-mentioned piston, all the pits in the first area are symmetrically arranged, and the symmetry axis is parallel to the first direction and intersects with the center line of the piston body.
[0017] Optionally, in the above-mentioned piston, the major axes of the pits in the second area, the third area and the fourth area are arranged along a first direction; the first direction is a straight line direction from the intake side to the exhaust side.
[0018] Optionally, in the above piston, all the pits in the second region are symmetrically arranged, and the symmetry axis is parallel to the first direction and intersects with the center line of the piston body;
[0019] All the pits in the third region are symmetrically arranged, and the symmetry axis is perpendicular to the first direction and intersects with the center line of the piston body;
[0020] All the pits in the fourth region are symmetrically arranged, and the symmetry axis is perpendicular to the first direction and intersects with the center line of the piston body.
[0021] Optionally, in the above piston, the size of each pit in the first region gradually decreases from the middle to the end, the middle is the middle of the first region along the second direction, and the end is the end of the first region along the second direction;
[0022] The size of each pit in the second region gradually decreases from the middle to the end, the middle is the middle of the second region along the second direction, and the end is the end of the second region along the second direction;
[0023] The size of each pit in the third region gradually decreases from the middle to the end, the middle is the middle of the third region along the first direction, and the end is the end of the third region along the first direction;
[0024] The size of each pit in the fourth region gradually decreases from the middle to the end, the middle is the middle of the fourth region along the first direction, and the end is the end of the fourth region along the first direction;
[0025] The first direction is a straight line direction from the intake side to the exhaust side, and the second direction is perpendicular to the first direction.
[0026] Optionally, in the above piston, the size of the pits in the central recessed area is smaller than the pits in the peripheral squeeze flow area; the arrangement spacing of the pits in the central recessed area is smaller than the pits in the peripheral squeeze flow area.
[0027] A gas fuel engine comprises a piston, wherein the piston is the piston described in any one of the above technical solutions.
[0028] The utility model provides a piston, comprising a piston body, the top surface of which comprises an outer squeeze flow area and a middle recessed area; the outer squeeze flow area surrounds the outer periphery of the middle recessed area; and pits are respectively arranged in the outer squeeze flow area and the middle recessed area.
[0029] It can be understood by those skilled in the art that, during the operation of a gas fuel engine, the supercharger increases the intake pressure and then allows the airflow to be input into the cylinder through the intake valve; as the lift of the intake valve increases, the flow in the cylinder becomes stronger, and a large-scale macroscopic tumble flow is gradually formed under the action of the cylinder head; for the tumble flow, the tumble flow form should be maintained as much as possible before the piston reaches the top dead center to maintain its kinetic energy, and the tumble flow should be broken up as much as possible before ignition to convert it into small-scale vortices, so as to improve combustion and increase the thermal efficiency of the gas fuel engine.
[0030] The airflow velocity in the middle recessed area of the piston is relatively high, and there is a large flow resistance between the gas flow and the middle recessed area. In the solution provided by the utility model, a pit is provided in the middle recessed area of the top surface of the piston body, and a flow dead zone is formed at the pit, so that the airflow contacts the dead zone airflow at the pit during the tumbling process, rather than contacting the surface of the pit, thereby reducing the friction force on the airflow, reducing the kinetic energy loss of the airflow, and allowing the airflow in the cylinder to better maintain the tumbling flow. At the same time, the pits provided in the peripheral squeeze flow area can guide the airflow and reduce the destructive effect of the peripheral squeeze flow area on the tumbling flow in the cylinder.
[0031] The pits in the above-mentioned central recessed area and the pits in the peripheral squeeze flow area act simultaneously, which can enable the airflow in the cylinder to better maintain tumbling, which is beneficial to the complete combustion of the gas fuel and is beneficial to improving the thermal efficiency of the gas fuel engine.
[0032] The utility model also provides a gas fuel engine using the piston, which has high thermal efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0033] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0034] Figure 1 A schematic diagram of a matching circuit structure provided by an embodiment of the utility model;
[0035] Figure 2 A schematic diagram of the structure of a trap circuit provided in an embodiment of the utility model;
[0036] in, Figure 1-Figure 2 middle:
[0037] Central depression area 10; peripheral squeeze flow area 20; first area 101; third area 102; second area 103; fourth area 104; pit 105. DETAILED DESCRIPTION
[0038] The utility model embodiment discloses a piston, wherein a pit is provided in the middle recessed area of the top surface of the piston body, and a flow dead zone is formed at the pit, so that the airflow contacts the dead zone airflow at the pit during the tumbling process, rather than contacting the surface of the pit, thereby reducing the friction force on the airflow and reducing the kinetic energy loss of the airflow. At the same time, the pits provided in the peripheral squeeze flow area can guide the airflow and reduce the destructive effect of the peripheral squeeze flow area on the tumbling flow in the cylinder. The simultaneous action of the pits in the middle recessed area and the peripheral squeeze flow area can better maintain the tumbling flow of the airflow in the cylinder, which is beneficial to the full combustion of the fuel and is beneficial to improving the thermal efficiency of the gas fuel engine. The utility model embodiment also discloses a gas fuel engine using the above piston, which has higher thermal efficiency.
[0039] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0040] See also Figure 1-Figure 2The embodiment of the utility model provides a piston, including a piston body, the top surface of the piston body includes a peripheral squeeze flow area 20 and a central recessed area 10; the peripheral squeeze flow area 20 is surrounded by the central recessed area 10; the peripheral squeeze flow area 20 and the central recessed area 10 are respectively provided with pits 105.
[0041] It can be understood by those skilled in the art that, during the operation of a gas fuel engine, the supercharger increases the intake pressure and then inputs the intake air into the cylinder through the intake valve; as the lift of the intake valve increases, the flow in the cylinder becomes stronger, and a large-scale macroscopic tumble flow is gradually formed under the action of the cylinder head; for the tumble flow, the tumble flow form should be maintained as much as possible before the piston reaches the top dead center to maintain its kinetic energy, and the tumble flow should be broken up as much as possible before ignition to convert it into small-scale vortices, so as to improve combustion and increase the thermal efficiency of the gas fuel engine.
[0042] The air flow velocity is relatively high in the middle recessed area 10 of the piston, and there is a large flow resistance between the gas flow and the middle recessed area 10. In the solution provided by the utility model, a pit 105 is provided in the middle recessed area 10 on the top surface of the piston body, and a flow dead zone is formed at the pit 105, so that the airflow contacts the dead zone airflow at the pit 105 during the tumbling process instead of contacting the surface of the pit 105, thereby reducing the friction force on the airflow, reducing the kinetic energy loss of the airflow, and enabling the airflow in the cylinder to better maintain the tumbling flow.
[0043] At the same time, the peripheral squeeze flow area 20 will reduce the tumble flow in the cylinder during the intake and compression process, and the pits 105 provided in the peripheral squeeze flow area 20 can guide the airflow, reduce the destructive effect of the peripheral squeeze flow area 20 on the tumble flow in the cylinder, and better maintain the tumble flow.
[0044] The dimples 105 in the middle recessed area 10 and the dimples 105 in the peripheral squeeze flow area 20 act simultaneously, which can better maintain the tumble flow of the airflow in the cylinder, facilitate the complete combustion of the gas fuel, and improve the thermal efficiency of the gas fuel engine.
[0045] In addition, a flow dead zone is formed at the pit 105 of the middle recessed area 10, and the gas in the dead zone constitutes a gas heat insulation layer, which can reduce the heat dissipation loss of the piston.
[0046] like Figure 1 As shown, the peripheral squeeze flow area 20 includes the following four areas:
[0047] A first region 101, the first region 101 is close to the intake side of the engine block;
[0048] A second region 103, the second region 103 is close to the exhaust side of the engine block;
[0049] A third region 102, the third region 102 is sandwiched between the first and second regions;
[0050] The fourth area 104 is sandwiched between the first area and the second area; the first area 101 , the second area 103 , the third area 102 and the fourth area 104 are all provided with pits 105 .
[0051] In the above piston, the recess 105 is configured to be elliptical.
[0052] In one embodiment, the first region 101 has a plurality of pits 105, and the long axis of each pit 105 is arranged along a first direction, and the first direction is a straight line direction from the air intake side to the exhaust side, such as Figure 1 shown.
[0053] In another embodiment, see Figure 2 Among all the pits 105 in the first area 101, the pit 105 located in the middle along the second direction is the central pit, and the long axis of the central pit is arranged along the first direction; the long axes of the other pits 105 in the first area 101 gradually approach the central pit 105 from the end away from the exhaust side to the end close to the exhaust side; the second direction is perpendicular to the first direction.
[0054] The long axis of the pit 105 of the middle depression area 10 is arranged along the second direction, such as Figure 1 , 2 In the solution provided in this embodiment, the pit 105 of the middle recessed area 10 adopts a structure in which the long axis is parallel to the second direction, which further adapts to the tumble flow organization form of the roof cylinder head of the gas fuel engine, reduces the friction between the gas flow in the cylinder and the piston surface to a greater extent, improves the flow capacity, and reduces the flow loss.
[0055] In some embodiments, all the pits 105 in the first region 101 are symmetrically arranged, and the axis of symmetry is parallel to the first direction and intersects with the center line of the piston body.
[0056] In the above piston, the long axes of the pits 105 in the second region 103, the third region 102 and the fourth region 104 are arranged along the first direction; the first direction is a straight line direction from the intake side to the exhaust side of the engine cylinder.
[0057] All the pits 105 in the second area 103 are symmetrically arranged, with the axis of symmetry parallel to the first direction and intersecting with the center line of the piston body; all the pits 105 in the third area 102 are symmetrically arranged, with the axis of symmetry perpendicular to the first direction and intersecting with the center line of the piston body; all the pits 105 in the fourth area 104 are symmetrically arranged, with the axis of symmetry perpendicular to the first direction and intersecting with the center line of the piston body.
[0058] In some embodiments, the size of each pit 105 in the first region 101 gradually decreases from the middle to the end, the middle is the middle of the first region 101 along the second direction, and the end is the end of the first region 101 along the second direction. The size of each pit 105 in the second region 103 gradually decreases from the middle to the end, the middle is the middle of the second region 103 along the second direction, and the end is the end of the second region 103 along the second direction. The size of each pit 105 in the third region 102 gradually decreases from the middle to the end, the middle is the middle of the third region 102 along the first direction, and the end is the end of the third region 102 along the first direction. The size of each pit 105 in the fourth region 104 gradually decreases from the middle to the end, the middle is the middle of the fourth region 104 along the first direction, and the end is the end of the fourth region 104 along the first direction.
[0059] In the above piston, the size of the pits 105 in the central recessed area 10 is smaller than the size of the pits in the peripheral squeezing flow area 20. The sizes of the pits 105 in the central recessed area 10 can be set to be consistent, or some smaller pits 105 can be arranged at the edge of the central recessed area 10 due to space size limitations. The pits 105 in the central recessed area 10 are arranged in staggered rows; the arrangement spacing of the pits 105 in the central recessed area 10 is smaller than the arrangement spacing of the pits 105 in the peripheral squeezing flow area 20.
[0060] In the piston provided by the embodiment of the utility model, the pits 105 of the peripheral squeeze flow area 20 in the top surface of the piston body are designed in a zoned manner, and the pits 105 in different areas adopt different size change rules and different arrangement methods, which can enhance the guiding effect of the airflow, minimize the destructive effect of the peripheral squeeze flow area 20 on the tumble flow, better maintain the tumble flow, and convert the kinetic energy carried by the tumble flow into turbulent kinetic energy of small-scale vortices before ignition, thereby improving combustion.
[0061] The piston body is arranged as a rotating body, and its squeezing ratio can be arranged to be 0.4-0.75.
[0062] The utility model embodiment also provides a gas fuel engine, comprising a piston, and the piston is the piston provided in the above embodiment.
[0063] The gas fuel engine provided in this embodiment uses the piston provided in the above embodiment, and has higher thermal efficiency. Of course, the gas fuel engine provided in this embodiment also has other effects related to the piston provided in the above embodiment, which will not be repeated here.
[0064] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.
[0065] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A piston, characterized in that: It includes a piston body, the top surface of which includes a peripheral squeeze flow area and a central recessed area; the peripheral squeeze flow area and the central recessed area are respectively provided with pits; the size of the pits in the central recessed area is smaller than the pits in the peripheral squeeze flow area; the arrangement spacing of the pits in the central recessed area is smaller than the pits in the peripheral squeeze flow area.
2. The piston according to claim 1, characterized in that The peripheral squeeze flow area includes: a first region, the first region being proximate to an intake side of an engine block; a second region, the second region being proximate to an exhaust side of the engine block; A third region, the third region being sandwiched between the first and second regions; The fourth area is sandwiched between the first area and the second area; the first area, the second area, the third area and the fourth area are all provided with pits.
3. The piston according to claim 2, characterized in that The pit is oval; The long axes of the pits in the first region are arranged along a first direction; the first direction is a straight line direction from the air intake side to the exhaust side; or Among all the pits in the first area, a pit located in the middle along the second direction is a central pit, and its long axis is arranged along the first direction; the long axes of other pits in the first area gradually approach the central pit from the end away from the exhaust side to the end close to the exhaust side; the second direction is perpendicular to the first direction.
4. The piston according to claim 3, characterized in that The long axes of the pits in the middle recessed area are arranged along the second direction.
5. The piston according to claim 3, characterized in that All the pits in the first region are symmetrically arranged, and the symmetry axis is parallel to the first direction and intersects with the center line of the piston body.
6. The piston according to claim 3, characterized in that The long axes of the pits in the second region, the third region and the fourth region are arranged along a first direction; the first direction is a straight line direction from the air intake side to the exhaust side.
7. The piston according to claim 6, characterized in that All the pits in the second region are symmetrically arranged, and the symmetry axis is parallel to the first direction and intersects with the center line of the piston body; All the pits in the third region are symmetrically arranged, and the symmetry axis is perpendicular to the first direction and intersects with the center line of the piston body; All the pits in the fourth region are symmetrically arranged, and the symmetry axis is perpendicular to the first direction and intersects with the center line of the piston body.
8. The piston according to claim 2, characterized in that The size of each pit in the first region gradually decreases from the middle to the end, the middle is the middle of the first region along the second direction, and the end is the end of the first region along the second direction; The size of each pit in the second region gradually decreases from the middle to the end, the middle is the middle of the second region along the second direction, and the end is the end of the second region along the second direction; The size of each pit in the third region gradually decreases from the middle to the end, the middle is the middle of the third region along the first direction, and the end is the end of the third region along the first direction; The size of each pit in the fourth region gradually decreases from the middle to the end, the middle is the middle of the fourth region along the first direction, and the end is the end of the fourth region along the first direction; The first direction is a straight line direction from the intake side to the exhaust side, and the second direction is perpendicular to the first direction.
9. A gas fuel engine comprising a piston, characterized in that: The piston is the piston according to any one of claims 1 to 8.