Device and control method for maintaining uniform pressure and temperature in an engine intake chamber

Abstract

This invention discloses a device and control method for maintaining uniform pressure and temperature in the engine intake chamber. The device includes a circulation pipe, with its two ends fixedly connected to the flywheel end and free end of the intake chamber, respectively. The intake passages of the first and last cylinders are connected to the intake chamber. Temperature and pressure detection devices are installed on both the first and last cylinder intake passages. A regulating valve is installed on the circulation pipe to adjust the flow rate of the boosted intercooled air in the circulation pipe. The detection devices are connected to the ECU, and the regulating valve is controlled by the ECU. The regulating valve is configured as an electronic throttle. The ECU monitors the intake pressure and temperature signals of each cylinder in real time, obtains a preset electronic throttle opening angle based on the temperature and pressure differences, and controls the opening angle of the electronic throttle according to the preset angle. This precisely controls and adjusts the flow rate of the boosted intercooled air in the circulation pipe, ensuring uniform intake pressure and temperature in each cylinder, improving engine knock pressure uniformity, exhaust temperature uniformity, and reducing vibration.

Description

Technical Field

[0001] This invention relates to the field of internal combustion engine technology, and in particular to a device and control method for maintaining uniform pressure and temperature in the engine intake chamber. Background Technology

[0002] Marine engines typically employ a box-type engine block design to ensure compact structure, reliable connections, and ease of maintenance. Figure 1 As shown, the engine block has a built-in intake chamber. Boosted intercooled air enters the intake chamber from the flywheel end (although in some engines, the boosted intercooled air enters from the free end). The cylinder head's intake duct directly connects to the intake chamber to obtain boosted intercooled air. During engine operation, especially under medium to high operating conditions (above 60% RPM), the inner wall of the engine block's intake chamber reaches approximately 80°C. Boosted intercooled air enters from one end of the engine block and flows to the other, gradually being heated. Furthermore, as engine operating conditions change, the pressure at both ends of the intake chamber differs. Therefore, the intake pressure and temperature of each cylinder will vary, meaning the quality of air participating in combustion in each cylinder is uneven. This results in inconsistent air-fuel ratios in each cylinder, poor power output consistency, manifesting as uneven engine knock pressure, uneven exhaust temperature, and excessive vibration. Summary of the Invention

[0003] In view of the above-mentioned defects in the prior art, the first technical problem to be solved by the present invention is to provide a device for maintaining the uniform pressure and temperature of the engine intake chamber, which can make the intake pressure and temperature of each cylinder uniform, improve the uniformity of engine detonation pressure and exhaust temperature, and reduce vibration.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0005] A device for maintaining uniform pressure and temperature in the intake chamber of an engine includes a circulation pipe, with its two ends fixedly connected to the flywheel end and the free end of the intake chamber, respectively. The intake passages of the first and last cylinders of the engine are connected to the intake chamber. Both the first and last cylinder intake passages are equipped with temperature and pressure detection devices. The circulation pipe is equipped with a regulating valve for adjusting the flow rate of the boosted intercooled air in the circulation pipe. The detection devices are connected to an ECU, and the regulating valve is controlled by the ECU.

[0006] Preferably, the regulating valve for adjusting the opening of the circulation pipeline is configured as an electronic throttle valve, which is electrically connected to the ECU.

[0007] Preferably, the detection device includes a pressure and temperature sensor.

[0008] Based on the same inventive concept, the second technical problem to be solved by the present invention is to provide a method for maintaining uniform pressure and temperature in the engine intake chamber, which can make the intake pressure and temperature of each cylinder uniform, improve the uniformity of engine detonation pressure and exhaust temperature, and reduce vibration.

[0009] A method for maintaining uniform pressure and temperature in the engine intake chamber, using the aforementioned device for maintaining uniform pressure and temperature in the engine intake chamber, includes the following steps:

[0010] S100: Obtain the real-time intake air temperature T1 of the first cylinder, the real-time intake air temperature T2 of the last cylinder, the real-time intake air pressure P1 of the first cylinder, and the real-time intake air pressure P2 of the last cylinder.

[0011] S200: The temperature difference ΔT is obtained based on the real-time intake temperature T1 of the first cylinder and the real-time intake temperature T2 of the last cylinder. At the same time, the pressure difference ΔP is obtained based on the real-time intake pressure P1 of the first cylinder and the real-time intake pressure P2 of the last cylinder.

[0012] S300: Based on the temperature difference ΔT and pressure difference ΔP, the preset electronic throttle opening angle is obtained;

[0013] S400: Based on the preset electronic throttle opening angle, the ECU controls the opening angle of the electronic throttle to maintain uniform pressure and temperature in the engine intake chamber.

[0014] Preferably, before step S100, the following step is further included:

[0015] S10. Obtain engine operating parameters;

[0016] S20. Determine whether the operating parameters meet the preset trigger conditions;

[0017] S30. If the operating parameters meet the preset trigger conditions, the electronic throttle control is triggered, and S100 is executed.

[0018] Preferred operating parameters include engine speed;

[0019] S10 includes: obtaining the engine speed n1;

[0020] S20 includes: determining whether the engine speed n1 exceeds the preset speed n;

[0021] If the engine speed n1 exceeds the preset speed n, the operating parameters meet the preset trigger conditions.

[0022] Preferred operating parameters include load;

[0023] S10 includes: acquiring engine load L1;

[0024] S20 includes: determining whether the load L1 exceeds the preset load L;

[0025] If the engine load L1 exceeds the preset load L, the operating parameters meet the preset trigger conditions.

[0026] Preferred setting: The preset speed n is 60% of the rated speed.

[0027] Preferred setting: The preset load L is 25% of the rated power.

[0028] Preferred: The preset electronic throttle opening angle is obtained from the preset map table, which is set according to the temperature difference, pressure difference and electronic throttle opening angle.

[0029] Specifically, S300 includes finding the corresponding preset electronic throttle opening angle by searching a preset map based on the temperature difference ΔT and pressure difference ΔP.

[0030] After adopting the above technical solution, the beneficial effects of the present invention are:

[0031] This invention provides a device for maintaining uniform pressure and temperature in the engine intake chamber. The two ends of a circulation pipe are fixedly connected to the flywheel end and the free end of the intake chamber, respectively. The intake passages of the first and last cylinders are connected to the intake chamber. Temperature and pressure detection devices are installed on both the first and last cylinder intake passages. A regulating valve is installed on the circulation pipe to adjust the flow rate of the boosted intercooled air in the circulation path. The detection devices are connected to the ECU, and the regulating valve is controlled by the ECU. The boosted intercooled air in the intake chamber flows from the free end to the flywheel end of the intake chamber through the circulation pipe, thus circulating the boosted intercooled air in the intake chamber. The ECU precisely controls and adjusts the flow of boosted intercooled air in the circulation pipe by controlling the opening of the regulating valve. This makes the pressure and temperature difference between the first and last cylinders approach zero. Since the pressure and temperature difference between the first and last cylinders is the largest among all cylinders, a more uniform pressure and temperature difference between the first and last cylinders will also make the pressure and temperature in all parts of the intake chamber more uniform. This ensures that the air-fuel ratio of each cylinder remains consistent, and that the combustion process and result of each cylinder are consistent. This improves the uniformity of engine detonation pressure and exhaust temperature, and reduces vibration.

[0032] The method for maintaining uniform pressure and temperature in the engine intake chamber of the present invention is implemented using the aforementioned device for maintaining uniform pressure and temperature in the engine intake chamber. The ECU monitors the intake pressure and temperature signals of each cylinder in real time, obtains the pressure and temperature difference between the first and last cylinders, and obtains a preset electronic throttle opening angle based on the temperature and pressure differences. The ECU controls the opening angle of the electronic throttle according to the preset electronic throttle opening angle, thereby precisely controlling and adjusting the flow rate of the boosted intercooled air in the circulation pipe, so that the pressure and temperature difference between the first and last cylinders approaches zero, thereby making the pressure and temperature of each part of the intake chamber more uniform, achieving a consistent air-fuel ratio in each cylinder, and ensuring that the combustion process and result in each cylinder are consistent, thereby improving the uniformity of engine detonation pressure, uniformity of exhaust temperature, and reducing vibration.

[0033] In order to maintain uniform pressure and temperature in the engine intake chamber, the engine speed must exceed the preset speed or the engine load must exceed the preset load before the electronic throttle control can be triggered. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of an engine intake system in the prior art;

[0035] Figure 2 This is a schematic diagram of the device for maintaining uniform pressure and temperature in the engine intake chamber according to the present invention.

[0036] Figure 3 This is a schematic diagram of the principle of the device for maintaining uniform pressure and temperature in the engine intake chamber according to the present invention.

[0037] Figure 4 This is a flowchart of the method for maintaining uniform pressure and temperature in the engine intake chamber according to the present invention;

[0038] Figure 5 This is another flowchart of the method for maintaining uniform pressure and temperature in the engine intake chamber according to the present invention;

[0039] In the diagram: 1. Circulation pipe; 2. Intake chamber; 3. Detection device; 4. Electronic throttle. Detailed Implementation

[0040] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments to further understand the purpose, solution and effect of the present invention, but it is not intended to limit the scope of protection of the appended claims.

[0041] In the description of this invention, it should be noted that the terms "first", "last", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0042] Furthermore, although terms such as "I-cylinder," "VI-cylinder," etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may only be used to distinguish one element, component, region, layer, or segment from another region, layer, or segment. Unless the context clearly indicates otherwise, terms such as "I," "VI," and other numerical terms used in this document do not imply any order or sequence. Therefore, the I-elements, components, regions, layers, or segments discussed below may be referred to as VI-elements, components, regions, layers, or segments without departing from the teachings of the exemplary embodiments.

[0043] In this embodiment, the application of a device for maintaining uniform pressure and temperature in the engine intake chamber to a six-cylinder engine is used as an example for illustration.

[0044] like Figure 2 As shown, a device for maintaining uniform pressure and temperature in the engine intake chamber includes a circulation pipe 1. The two ends of the circulation pipe 1 are fixedly connected to the flywheel end and the free end of the intake chamber 2, respectively. The intake passages of the first and last cylinders of the engine are connected to the intake chamber 2. For a six-cylinder engine, this means the intake passages of cylinders I and VI are connected to the intake chamber 2. Temperature and pressure detection devices 3 are installed on both the intake passages of cylinders I and VI. A regulating valve is installed on the circulation pipe 1 to adjust the flow rate of the boosted intercooled air in the circulation pipeline. The detection devices are connected to the ECU, and the regulating valve is controlled by the ECU.

[0045] In some embodiments, the regulating valve for adjusting the opening of the circulation pipeline is configured as an electronic throttle valve 4, which is electrically connected to the ECU. Of course, the electronic throttle valve 4 can also be other electric butterfly valves.

[0046] Preferably, the detection device 3 includes a pressure and temperature sensor. Of course, the detection device 3 may also include a pressure sensor and a temperature sensor respectively.

[0047] A device for maintaining uniform pressure and temperature in the engine intake chamber circulates cool air during intake chamber pressurization via a circulation pipe 1. The optimal amount of cool air circulating during intake chamber pressurization is calculated using an algorithm model. This invention controls the amount of cool air flowing during intake chamber pressurization, resulting in uniform intake pressure and temperature in each cylinder, improving engine knock pressure uniformity, exhaust temperature uniformity, and reducing vibration.

[0048] In some embodiments, the circulation pipe described above is made of stainless steel. Of course, other high-temperature alloy pipes made of high-temperature resistant materials can also be used.

[0049] The engine of this invention can be a six-cylinder engine, a four-cylinder engine, or an eight-cylinder engine, etc. For a four-cylinder engine, the first and last cylinders refer to cylinders I and VI, while for an eight-cylinder engine, the first and last cylinders refer to cylinders I and VIII. The same logic applies to engines with different numbers of cylinders, and will not be elaborated upon here.

[0050] like Figures 3 to 5 As shown, a method for maintaining uniform pressure and temperature in the engine intake chamber, implemented using the aforementioned device for maintaining uniform pressure and temperature in the engine intake chamber, includes the following steps:

[0051] S100: Obtain the real-time intake air temperature T1 of the first cylinder, the real-time intake air temperature T2 of the last cylinder, the real-time intake air pressure P1 of the first cylinder, and the real-time intake air pressure P2 of the last cylinder. For a six-cylinder engine, the specific steps are as follows: Obtain the real-time intake air temperature T1 and real-time intake air pressure P1 of cylinder I through the detection device 3 of cylinder I intake port, and at the same time obtain the real-time intake air temperature T2 and real-time intake air pressure P2 of cylinder VI through the detection device 3 of cylinder VI intake port.

[0052] S200. The temperature difference ΔT is obtained from the real-time intake temperature T1 of the first cylinder and the real-time intake temperature T2 of the last cylinder, ΔT=T1-T2; at the same time, the pressure difference ΔP is obtained from the real-time intake pressure P1 of the first cylinder and the real-time intake pressure P2 of the last cylinder, ΔP=P1-P2.

[0053] S300: Based on the temperature difference ΔT and pressure difference ΔP, the preset opening angle of the electronic throttle valve 4 is obtained;

[0054] S400: According to the preset opening angle of the electronic throttle valve 4, the ECU controls the opening angle of the electronic throttle valve 4, thereby adjusting the flow rate of the boosted intercooled air in the circulation pipe 1 to maintain the pressure and temperature of the engine intake chamber 2 uniformly.

[0055] Prior to S100 above, the following steps are also included:

[0056] S10. Obtain engine operating parameters;

[0057] S20. Determine whether the operating parameters meet the preset trigger conditions;

[0058] S30. If the operating parameters meet the preset trigger conditions, the electronic throttle valve 4 control is triggered, and S100 is executed.

[0059] If the above operating parameters include engine speed;

[0060] S10 includes: obtaining the engine speed n1;

[0061] S20 includes: determining whether the engine speed n1 exceeds the preset speed n;

[0062] If the engine speed n1 exceeds the preset speed n, the operating parameters meet the preset trigger conditions.

[0063] Preferably, the preset speed n is 60% of the rated speed; that is, when the engine speed n1 exceeds 60% of the rated speed, the operating parameters meet the preset trigger conditions.

[0064] If the above operating parameters include load;

[0065] S10 includes: acquiring engine load L1;

[0066] S20 includes: determining whether the load L1 exceeds the preset load L; if the engine load L1 exceeds the preset load L, the operating parameters meet the preset trigger conditions.

[0067] Preferably, the preset load L is 25% of the rated power; that is, when the engine load L1 exceeds 25% of the rated power, the operating parameters meet the preset triggering conditions.

[0068] The preset opening angle of the electronic throttle body 4 is obtained from the preset map table, which is set based on the temperature difference, pressure difference, and the opening angle of the electronic throttle body 4.

[0069] Specifically, S300 involves finding the corresponding preset electronic throttle opening angle based on the temperature difference ΔT and pressure difference ΔP by searching a preset map.

[0070] For example, under certain operating conditions, the pressure and temperature sensor measures the intake air temperature of cylinder I to be 24℃ and the intake pressure to be 200kPa, while the intake air temperature of cylinder VI is 20℃ and the intake pressure is 190kPa. Therefore, ΔT = 24℃ - 20℃ = 4℃, and ΔP = 200kPa - 190kPa = 10kPa. Based on the pressure difference ΔP and temperature difference ΔT between cylinders I and VI, and considering the current engine speed n1 or load L1, the ECU reads the pre-set electronic throttle valve 4 opening angle value from the map. If the engine speed n1 exceeds 60% of the rated speed, the condition is triggered; or if the load L1 exceeds 25% of the rated power, the condition is triggered. The ECU then controls the opening angle of the electronic throttle valve 4, adjusting the flow rate of the boosted intercooled air in the circulation pipe 1 to maintain uniform pressure and temperature in the engine intake chamber 2.

[0071] like Figure 4 As shown, when the engine is the primary propulsion engine, the ECU is triggered to control the electronic throttle when the engine speed n1 is greater than 60% of the rated speed. The pressure and temperature sensors collect the intake pressure and temperature signals of cylinders I and VI and transmit them to the ECU. The ECU reads the preset electronic throttle opening angle value from the map table based on the intake pressure difference ΔP and temperature difference ΔT between cylinders I and VI, and issues a command to control the electronic throttle opening angle, opening the electronic throttle to adjust the flow of pressurized intercooled air in the intake chamber from the end (free end) to the beginning (flywheel end) through the circulation pipe 1. This circulates the pressurized intercooled air in the intake chamber, making the pressure and temperature in each part of the chamber more uniform. The intake pressure difference between each cylinder is controlled between 3 kPa and 6 kPa, and the intake temperature difference between each cylinder is controlled between 0.5℃ and 1℃. Ideally, the pressure and temperature difference between the first and last cylinders approaches zero.

[0072] The ECU monitors the intake pressure and temperature signals of each cylinder in real time, controls and adjusts the opening angle of the electronic throttle, and precisely controls the circulation flow of the intercooled air in the boost system. This ensures that the differences in intake pressure and temperature between cylinders remain within a controlled range, achieving an air-fuel ratio (λ) difference of less than or equal to 2% between cylinders. This ensures that the combustion process and results in each cylinder are consistent, thereby improving engine knock pressure uniformity, exhaust temperature uniformity, and reducing vibration. The electronic throttle is controlled by a rotary motor, and its rotation angle can communicate with the ECU in real time.

[0073] In summary, the intake pressure difference between cylinder I and cylinder VI of an engine is typically controlled between 3 kPa and 6 kPa, and the temperature difference between 0.5℃ and 1℃. In practical applications, precise adjustments are made based on actual operating conditions and engine design.

[0074] like Figure 5As shown, when the engine is a generator engine, the ECU is triggered to control the electronic throttle when the load L1 is greater than 25% of the rated power. Typically, the load L1 is identified by the boost air pressure, and the engine load rate corresponding to the boost air pressure is determined through experimental calibration.

[0075] The present invention provides a method for maintaining uniform pressure and temperature in the engine intake chamber. By using a device to control the flow of cold air during intake chamber pressurization, the intake pressure and temperature of each cylinder are made uniform, thereby improving the uniformity of engine detonation pressure and exhaust temperature, and reducing vibration.

[0076] This invention is not limited to the above embodiments. All improvements made based on the concept, principle, structure and method of this invention are within the protection scope of this invention.

Claims

1. A device for maintaining uniform pressure and temperature in the engine intake chamber, characterized in that: The system includes a circulation pipe (1), with its two ends fixedly connected to the flywheel end and the free end of the intake chamber (2), respectively. The intake passages of the first cylinder and the last cylinder of the engine are connected to the intake chamber (2). Both the first cylinder intake passage and the last cylinder intake passage are equipped with a detection device (3) for detecting temperature and pressure. The circulation pipe (1) is equipped with a regulating valve for regulating the flow rate of the boosted cold air in the circulation pipeline. The detection device (3) is connected to the ECU, and the regulating valve is controlled by the ECU.

2. The device for maintaining uniform pressure and temperature in the engine intake chamber as described in claim 1, characterized in that: The regulating valve for adjusting the opening of the circulation pipeline is set as an electronic throttle valve (4), which is electrically connected to the ECU.

3. The device for maintaining uniform pressure and temperature in the engine intake chamber as described in claim 1, characterized in that: The detection device (3) includes a pressure and temperature sensor.

4. A method for maintaining uniform pressure and temperature in the engine intake chamber, using the apparatus for maintaining uniform pressure and temperature in the engine intake chamber as described in claim 2, characterized in that: Includes the following steps: S100: Obtain the real-time intake air temperature T1 of the first cylinder, the real-time intake air temperature T2 of the last cylinder, the real-time intake air pressure P1 of the first cylinder, and the real-time intake air pressure P2 of the last cylinder. S200: The temperature difference ΔT is obtained based on the real-time intake temperature T1 of the first cylinder and the real-time intake temperature T2 of the last cylinder. At the same time, the pressure difference ΔP is obtained based on the real-time intake pressure P1 of the first cylinder and the real-time intake pressure P2 of the last cylinder. S300. Based on the temperature difference ΔT and pressure difference ΔP, the preset opening angle of the electronic throttle (4) is obtained. S400. According to the preset opening angle of the electronic throttle valve 4, the ECU controls the opening angle of the electronic throttle valve (4) to maintain the pressure and temperature of the engine intake chamber (2) uniform.

5. The method for maintaining uniform pressure and temperature in the engine intake chamber as described in claim 4, characterized in that: Prior to S100, the following steps are also included: S10. Obtain engine operating parameters; S20. Determine whether the operating parameters meet the preset trigger conditions; S30. If the operating parameters meet the preset trigger conditions, the electronic throttle valve (4) is triggered to control and execute S100.

6. The method for maintaining uniform pressure and temperature in the engine intake chamber as described in claim 5, characterized in that: Operating parameters include engine speed; S10 includes: obtaining the engine speed n1; S20 includes: determining whether the engine speed n1 exceeds the preset speed n; If the engine speed n1 exceeds the preset speed n, the operating parameters meet the preset trigger conditions.

7. The method for maintaining uniform pressure and temperature in the engine intake chamber as described in claim 5, characterized in that: Operating parameters include load; S10 includes: acquiring engine load L1; S20 includes: determining whether the load L1 exceeds the preset load L; If the engine load L1 exceeds the preset load L, the operating parameters meet the preset trigger conditions.

8. The method for maintaining uniform pressure and temperature in the engine intake chamber as described in claim 6, characterized in that: The preset speed n is 60% of the rated speed.

9. The method for maintaining uniform pressure and temperature in the engine intake chamber as described in claim 8, characterized in that: The preset load L is 25% of the rated power.

10. The method for maintaining uniform pressure and temperature in the engine intake chamber as described in claim 6, characterized in that: The preset opening angle of the electronic throttle (4) is obtained from the preset map table, which is set according to the temperature difference, pressure difference and the opening angle of the electronic throttle (4). The S300 specifically includes finding the corresponding preset electronic throttle opening angle (4) by searching a preset map based on the temperature difference ΔT and pressure difference ΔP.

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