阅读说明：本技术 一种谐振进气的柴油机系统 (Diesel engine system with resonant air intake ) 是由 余侃 杨书乔 王明 李先南 张文正 于 2020-12-21 设计创作，主要内容包括：本发明公开了一种谐振进气的柴油机系统,包括压气机、进气总管、柴油机和谐振装置。压气机用于向柴油机系统输入空气。进气总管与压气机连通。柴油机具有多个气缸,多个气缸均连通至进气总管,且多个气缸并联设置。谐振装置设置于进气总管的远离压气机的端部,谐振装置包括空腔,空腔具有开口端与封闭端,开口端与进气总管连通。谐振装置还包括至少两个谐振阀,至少两个谐振阀可开闭地设置于空腔,以使得空腔的与进气总管连通的空间形成谐振腔。根据本发明的谐振进气的柴油机系统,设置有端部封闭的谐振装置,柴油机产生的进气压力波能够进入谐振装置后反射形成谐振波,谐振波能够与进气压力波至少部分抵消,进而提高柴油机各个气缸的进气一致性。(The invention discloses a diesel engine system with resonant air intake, which comprises an air compressor, an air intake manifold, a diesel engine and a resonant device. The compressor is used for inputting air to the diesel engine system. The air inlet manifold is communicated with the air compressor. The diesel engine is provided with a plurality of cylinders which are communicated to the air inlet main pipe and are arranged in parallel. The resonance device is arranged at the end part, far away from the compressor, of the air inlet main pipe and comprises a cavity, the cavity is provided with an opening end and a closed end, and the opening end is communicated with the air inlet main pipe. The resonance device also comprises at least two resonance valves which can be opened and closed and are arranged in the cavity, so that the space of the cavity communicated with the air inlet main pipe forms a resonance cavity. According to the diesel engine system with the resonance air intake, which is disclosed by the invention, the resonance device with the closed end part is arranged, the air intake pressure wave generated by the diesel engine can enter the resonance device and then is reflected to form the resonance wave, and the resonance wave and the air intake pressure wave can be at least partially counteracted, so that the air intake consistency of each cylinder of the diesel engine is improved.)

1. A resonant intake diesel engine system, comprising:

the air compressor is used for inputting air to the diesel engine system;

the air inlet main pipe is communicated with the air compressor;

the diesel engine is provided with a plurality of cylinders which are communicated to the air inlet main pipe and are arranged in parallel; and

the resonance device is arranged at the end part, far away from the compressor, of the air inlet main pipe and comprises a cavity, the cavity is provided with an opening end and a closed end, and the opening end is communicated with the air inlet main pipe;

the resonance device further comprises at least two resonance valves, and the at least two resonance valves are arranged in the cavity in an openable and closable mode, so that a space of the cavity, which is communicated with the air inlet main pipe, forms a resonance cavity.

2. The diesel engine system of claim 1, further comprising a control device in signal connection with the at least two resonance valves, the control device configured to control the length of the resonance chamber by controlling the at least two resonance valves to open and close;

wherein the length of the resonant cavity is configured as the distance between the first closed state of the resonant valve and the open end in a direction away from the intake manifold;

and/or the cavity is configured as the resonant cavity when the at least two resonant valves are both in an open state.

3. The diesel engine system of claim 2, wherein the control device is in signal communication with the diesel engine, the control device configured to control the length of the resonant cavity based on a speed of the diesel engine.

4. The diesel engine system of claim 3, wherein the diesel engine reaches an idle speed when the diesel engine is in an idle state, and the control device is configured to control both of the at least two resonance valves to be in a closed state.

5. The diesel engine system of claim 4, wherein the control device is configured to control both of the at least two resonance valves to be in an open state when the diesel engine reaches a first rotational speed that is greater than the idle rotational speed of the diesel engine and less than a rated rotational speed of the diesel engine.

6. The diesel engine system of claim 5, wherein the control device is configured to control at least one of the resonator valves proximate the closed end of the cavity to close when the diesel engine reaches a second speed, the second speed being greater than the first speed and less than or equal to the nominal speed.

7. The diesel engine system of claim 5, wherein the control device is configured to control the at least two resonance valves to open sequentially in a direction away from the intake manifold when the diesel engine is in a loading process in which the rotation speed is increased from the idle rotation speed to the first rotation speed.

8. The diesel engine system of claim 6, wherein when the diesel engine is in a load shedding process in which the rotation speed is reduced from the second rotation speed to the idle rotation speed, the control device is configured to control the at least two resonance valves to be closed in sequence in a direction approaching the intake manifold.

9. The diesel engine system of claim 5, wherein a ratio of the first rotational speed to the rated rotational speed is 0.65:1 to 0.75: 1.

10. The diesel engine system of claim 6, wherein when the diesel engine reaches the rated rotation speed, the control device is configured to control the length ratio of the resonant cavity to the cavity to be 0.65: 1-0.75: 1.

11. The diesel engine system of any of claims 1-10, wherein a ratio of a radial cross-sectional area of the cavity to a radial cross-sectional area of the intake manifold is 0.25:1 to 1: 1.

Technical Field

The invention relates to the technical field of marine diesel engines, in particular to a diesel engine system with resonant air intake.

Background

At present, most marine diesel engines are multi-cylinder diesel engines, but the applicant finds that air intakes of a plurality of cylinders are different from one another, namely the problem that the air intake consistency of the existing multi-cylinder diesel engines is poor.

Specifically, there is a difference in the amount and pressure of intake air per cylinder, resulting in a difference in the combustion speed of each cylinder. The prior methods for improving the consistency of each cylinder generally comprise two methods, namely, the oil injection timing and the pulse width of each cylinder are adjustable through a common rail oil injection system or an electronic unit pump; secondly, a throttle valve is installed on an intake manifold of each cylinder to respectively adjust the air intake amount of each cylinder, and the method is common in high-speed gas engines.

However, the problems of poor intake uniformity are not solved from the source in both of the solutions, and the reliability of the parts is highly required.

Therefore, there is a need for a resonant intake diesel engine system that at least partially addresses the above problems.

Disclosure of Invention

In this summary, concepts in a simplified form are introduced that are further described in the detailed description. This summary of the invention is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

To at least partially solve the above problems, the present invention provides a resonant intake diesel engine system comprising:

the air compressor is used for inputting air to the diesel engine system;

the air inlet main pipe is communicated with the air compressor;

the diesel engine is provided with a plurality of cylinders which are communicated to the air inlet main pipe and are arranged in parallel; and

the resonance device is arranged at the end part, far away from the compressor, of the air inlet main pipe and comprises a cavity, the cavity is provided with an opening end and a closed end, and the opening end is communicated with the air inlet main pipe;

the resonance device further comprises at least two resonance valves, and the at least two resonance valves are arranged in the cavity in an openable and closable mode, so that a space of the cavity, which is communicated with the air inlet main pipe, forms a resonance cavity.

According to the diesel engine system with the resonance air intake, which is disclosed by the invention, the resonance device with the closed end part is arranged, the air intake pressure wave generated by the diesel engine air intake system can enter the resonance device and then be reflected to form resonance wave, and the resonance wave can be at least partially counteracted with the air intake pressure wave, so that the air intake consistency of each cylinder of the diesel engine is improved; and when the rotating speed of the diesel engine is changed, the at least two resonance valves can be opened and closed to change the length of the resonant cavity, so that the phase and/or the wavelength of the resonant waves reflected by the resonant cavity are changed, and the resonant cavity can adapt to the changed intake pressure fluctuation.

Further, the diesel engine system further comprises a control device, the control device is in signal connection with the at least two resonance valves, and the control device is configured to control the opening and closing of the at least two resonance valves so as to control the length of the resonance cavity;

wherein the length of the resonant cavity is configured as the distance between the first closed state of the resonant valve and the open end in a direction away from the intake manifold;

and/or the cavity is configured as the resonant cavity when the at least two resonant valves are both in an open state.

Further, the control device is in signal connection with the diesel engine, and the control device is configured to control the length of the resonant cavity according to the rotating speed of the diesel engine. According to the arrangement, the control device can control the opening and closing of the resonance valve through the rotating speed of the diesel engine, so that the length of the resonant cavity is changed, and the resonance wave and the intake pressure wave can be partially offset all the time.

Further, when the diesel engine is in an idle state, the diesel engine reaches an idle rotation speed, and the control device is configured to control the at least two resonance valves to be in a closed state.

Further, when the diesel engine reaches a first rotation speed, which is greater than the idle rotation speed of the diesel engine and less than a rated rotation speed of the diesel engine, the control device is configured to control both of the at least two resonance valves to be in an open state.

Further, the control device is configured to control at least one of the resonance valves close to the closed end of the cavity to close when the diesel engine reaches a second rotational speed, which is greater than the first rotational speed and less than or equal to the rated rotational speed.

Further, when the diesel engine is in a loading process that the rotation speed is increased from the idle rotation speed to the first rotation speed, the control device is configured to control the at least two resonance valves to be opened in sequence in a direction away from the air inlet main pipe.

Further, when the diesel engine is in a load shedding process in which the rotation speed is reduced from the second rotation speed to the idle rotation speed, the control device is configured to control the at least two resonance valves to close sequentially in a direction approaching the intake manifold.

Further, the ratio of the first rotating speed to the rated rotating speed is 0.65: 1-0.75: 1.

Further, when the diesel engine reaches the rated rotating speed, the control device is configured to control the length ratio of the resonant cavity to the cavity to be 0.65: 1-0.75: 1.

Further, the ratio of the radial sectional area of the cavity to the radial sectional area of the air inlet main pipe is 0.25: 1-1: 1.

Drawings

The following drawings of the invention are included to provide a further understanding of the invention. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

In the drawings:

FIG. 1 is a schematic diagram of a resonant intake diesel engine system according to a preferred embodiment of the present invention;

FIG. 2 is a schematic diagram of the resonant assembly of FIG. 1, wherein both resonant valves are in a closed position;

FIG. 3 is a schematic diagram of the resonant assembly of FIG. 1, wherein both resonant valves are in an open state;

FIG. 4 is a schematic structural view of the resonator device of FIG. 1 with one resonator valve in an open state and the other resonator valve in a closed state;

FIG. 5 is a schematic signal connection diagram of the control device of FIG. 1;

FIG. 6 is a schematic diagram of the control strategy for a resonant intake diesel engine system according to a preferred embodiment of the present invention;

FIG. 7 is a schematic illustration of intake pressure fluctuations for a resonant intake diesel engine system according to a preferred embodiment of the present invention; and

FIG. 8 is a schematic illustration of intake pressure fluctuation and resonance wave cancellation for a resonant intake diesel engine system according to a preferred embodiment of the present invention.

Description of reference numerals:

100: resonant intake diesel engine system 110: gas compressor

120: air cooler 130: diesel engine

131: the cylinder 140: air inlet main pipe

141: intake branch pipe 150: exhaust manifold

151: exhaust branch pipe 160: supercharging device

170: the resonance device 171: resonance valve

172: first resonance valve 173: second resonance valve

174: cavity 175: resonant cavity

176: open end 177: closed end

180: the control device 181: memory module

Detailed Description

In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without one or more of these specific details. In other instances, well-known features have not been described in order to avoid obscuring the invention.

In the following description, a detailed description will be given in order to thoroughly understand the present invention. It is to be understood that these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of these exemplary embodiments to those skilled in the art. It is apparent that the implementation of the embodiments of the invention is not limited to the specific details familiar to those skilled in the art. The following detailed description of the preferred embodiments of the invention, however, the invention is capable of other embodiments in addition to those detailed.

It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the invention. As used herein, the singular is intended to include the plural unless the context clearly dictates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

Ordinal words such as "first" and "second" are referred to herein merely as labels, and do not have any other meaning, such as a particular order, etc. Also, for example, the term "first component" does not itself imply the presence of "second component", and the term "second component" does not itself imply the presence of "first component". It is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "inner", "outer", and the like are used herein for purposes of illustration only and are not limiting.

Exemplary embodiments according to the present invention will now be described in more detail with reference to the accompanying drawings.

Fig. 1 shows a resonant intake diesel engine 130 system 100 of a preferred embodiment of the present invention, which includes a compressor 110, an intake manifold 140, intake branches 141, an exhaust manifold 150, exhaust branches 151, a supercharging device 160, a diesel engine 130, and an air cooler 120.

The compressor 110 is used to input air to the diesel engine 130, and may be an air compressor or the like. An intake manifold 140 communicates with the compressor 110 for receiving air delivered by the compressor 110 and delivering it to the diesel engine 130. The diesel engine 130 is in communication with an intake manifold 140. Specifically, the diesel engine 130 has a plurality of cylinders 131, and the plurality of cylinders 131 are preferably connected in parallel to the intake manifold 140. Alternatively, each of the plurality of cylinders 131 is connected to the intake manifold 140 through an intake manifold 141.

The exhaust branch pipes 151 are connected to the respective cylinders 131 in parallel, and are gathered to an exhaust manifold 150. The exhaust manifold 150 can then lead to a boosting device 160 for turbocharging. Further, an air cooler 120 is preferably provided to the intake manifold 140 to cool the air.

In long-term research, it has been found that in the diesel engine 130 having the plurality of cylinders 131 described above, the intake branch 141 that delivers air to each cylinder 131 does not simply draw a steady-pressure airflow from the intake manifold 140.

Gas fluctuations in the diesel engine intake system are extremely complex, as fluctuations in gas flow are generated during intake by each cylinder 131. The frequency of the intake pressure fluctuation has a certain relation with the on-off time of the valve of the cylinder 131, the intake flow rate of the diesel engine, the friction resistance and other parameters, and the amplitude of the intake pressure fluctuation is related to the volume of the intake passage, the supercharging pressure and other parameters.

The combined effect of these factors is that the diesel engine 130 will generate a substantially sinusoidal intake pressure fluctuation (such as the curve shown in fig. 7) with a substantially constant frequency and amplitude at a substantially constant speed. When the rotation speed of the diesel engine 130 is changed, the frequency and amplitude of the intake pressure fluctuation are also changed.

Specifically, differences in the amount of air and/or pressure entering each cylinder 131 may result in different excess air ratios within each cylinder, and thus different combustion speeds for each cylinder of the diesel engine 130. The deviation between the detonation pressure and the exhaust temperature of each cylinder 131 is shown, which has a great influence on the performance of the diesel engine 130.

For example, on the premise that the fuel injection amount of each cylinder is consistent, the cylinder 131 with a large intake air amount has a high excess air coefficient and a high combustion speed, and therefore, the explosion pressure is high and the exhaust temperature is low; otherwise, the detonation pressure is low and the exhaust temperature is high. With the development of supercharging technology, the supercharging pressure is higher and higher, which leads to the more prominent contradiction caused by the consistency of each cylinder. Moreover, the problem of cylinder consistency of the two-stage supercharging system is more obvious due to the fact that the supercharging pressure is higher.

For this purpose, reference is made to fig. 1, 2, 3 and 4. The resonant intake diesel engine 130 system 100 of the present invention further includes a resonant device 170. Which is preferably disposed at the end of the intake manifold 140 remote from the compressor 110. The resonator device 170 has a closed-ended cavity 174 therein, i.e., the cavity 174 has an open end 176 and a closed end 177. Also, the open end 176 of the cavity 174 communicates with the intake manifold 140.

For example, in the illustrated embodiment, one end of the intake manifold 140 communicates with the compressor 110 and the other end communicates with an open end 176 of the cavity 174 of the resonator device 170. In an embodiment not shown, the resonator device 170 may also be connected to a middle portion of the intake manifold 140.

Preferably, the resonance device 170 further includes at least two resonance valves 171, and the at least two resonance valves 171 are openably and closably disposed in the cavity 174 such that a space of the cavity 174 communicating with the intake manifold 140 forms a resonance chamber 175. Wherein, when at least two resonance valves 171 are in an open state, the entire cavity 174 is formed as the resonance cavity 175.

In the embodiment shown in fig. 1 to 4, the resonator device 170 may be a section of pipe with one end closed. Preferably, the ratio of the radial cross-sectional area of the cavity 174 to the intake manifold 140 is 0.25:1 to 1: 1. More preferably, the ratio of the radial cross-sectional area of the cavity 174 to the intake manifold 140 is 0.3:1 to 1: 1. In this embodiment, the ratio of the radial cross-sectional area of the cavity 174 to the intake manifold 140 is 0.3:1, i.e., the radial cross-sectional area of the cavity 174 is one third of the radial cross-sectional area of the intake manifold 140. However, the larger the radial cross-sectional area of the cavity 174, the better the resonant effect of the cavity 175. Illustratively, the ratio of the radial cross-sectional area of the cavity 174 to the intake manifold 140 is 1:1 for optimal results.

In the present embodiment, the resonance device 170 is provided with two resonance valves 171, i.e., a first resonance valve 172 and a second resonance valve 173. Wherein a first resonator valve 172 may be provided at the open end 176 to control the opening or closing of the entire resonator device 170. A second resonator valve 173 is openably and closably disposed in the cavity 174 of the resonator device 170 so that it can divide the cavity 174 into two parts when closed. Illustratively, with the first resonator valve 172 open and the second resonator valve 173 closed, the space of the cavity 174 near the closed end 177 is not in communication with the intake manifold 140, and the space of the cavity 174 near the open end 176 forms the resonant cavity 175.

Thus, the first resonance valve 172 can control whether the resonance device 170 is opened or not, and the second resonance valve 173 can perform switching of the length of the resonance chamber 175. That is, the length of the resonance chamber 175 is the distance between the first resonance valve 172 and the second resonance valve 173, or the length of the resonance chamber 175 is the length of the entire cavity 174.

Furthermore, by changing the length of the resonator 175, the phase and/or wavelength of the resonance wave can be changed after the intake pressure fluctuation is reflected in the resonator 175 to form the resonance wave, so that the resonance wave can be cancelled with the intake pressure fluctuation part all the time (as shown in fig. 8), the amplitude of the intake pressure fluctuation is reduced, and finally, the intake consistency of each cylinder 131 of the diesel engine 130 is improved.

It will be appreciated that the resonator device 170 may also be provided with more resonator valves 171, such as three, four, five, six or more resonator valves, etc., so that the length of the resonator 175 can be adjusted within a finer range, and thus can be more adapted to the variation of the intake air fluctuation caused by the variation of the rotation speed of the diesel engine 130.

In this case, the length of the resonance chamber 175 is preferably configured as the distance between the first resonance valve 171 in the closed state and the open end 176 in the direction away from the intake manifold 140, or the length of the resonance chamber 175 when all the resonance valves 171 are open is the length of the cavity 174 of the entire resonance device 170.

Preferably, the diesel engine 130 control system may further comprise a control device 180 (shown in fig. 1 and 5), and the control device 180 may be in signal connection with the resonance device 170, specifically, the control device 180 is in signal connection with each resonance valve 171 in the resonance device 170. Thus, the control device 180 can control the opening and closing of all the resonance valves 171, thereby controlling the length of the resonance chamber 175.

More preferably, the control device 180 can also be in signal connection with the diesel engine 130. Therefore, the control device 180 can detect the current rotation speed of the diesel engine 130, determine the length of the resonant cavity 175 suitable for the current rotation speed, and further control the opening and closing of the corresponding resonant valve 171, thereby finally achieving the effect that the resonant wave and the intake pressure wave can be partially cancelled all the time in the operation process of the diesel engine 130.

The control device 180 is preferably provided with a memory module 181, in which the corresponding relationship between the rotation speed of the diesel engine 130 and the length of the resonant cavity 175 can be recorded, and the control device 180 can control the opening and closing of the resonant valve 171 based on the recorded relationship.

For example, the memory module 181 may store the following correspondence relationship.

When the diesel engine 130 is started and can be in an idle state, the rotation speed is an idle rotation speed N_minIn this case, in order to increase the response speed of the diesel engine 130, the intake pressure fluctuation is sufficiently utilized and the resonance device 170 is not turned on. That is, the rotation speed of the diesel engine 130 is the idling rotation speed N_minAt this time, the resonance valve 171 is fully closed (as shown in fig. 2, in a state where both the first resonance valve 172 and the second resonance valve 173 are closed).

When the rotation speed of the diesel engine 130 reaches the rated rotation speed N_maxWhen the length ratio of the resonant cavity 175 to the cavity 174 is preferably 0.65:1 to 0.75: 1. More preferably, the length of the cavity 175 and the cavity 174 is 0.7: 1. That is, when the diesel engine 130 reaches the maximum rotational speed (or the rated rotational speed N)_max) In this case, the length of the cavity 175 needs to be about 70% of the length of the cavity 174. At this time, the resonance valve 171 needs to be partially opened and partially closed, for example, in a state where the first resonance valve 172 is opened but the second resonance valve 173 is closed as shown in fig. 4.

It has been found that when the resonant valve 171 is fully opened, i.e. when the length of the resonant cavity 175 is at a maximum (in which the cavity 174 is the resonant cavity 175), the corresponding rotational speed N is not the maximum load of the rotational speed of the diesel engine 130_maxSetting the rotation speed at this time to N₀. Then N is₀And N_maxThe ratio of (A) to (B) is preferably 0.65:1 to 0.75: 1. More preferably 0.7: 1. That is, when the current rotational speed is about 70% of the rated rotational speed, the resonance valve 171 needs to be fully opened to cancel the resonance wave and the intake air pulsation.

Thus, the length of cavity 175 needs to be increased and then decreased as the speed of diesel engine 130 increases.

As described above, control device 180 can control opening and closing of resonance valve 171 according to the following logical relationship.

Let the current rotational speed of the diesel engine 130 be n.

If N is equal to N_minThe control device 180 is configured to control all the resonance valves 171 to be in the closed state.

If N is present_min＜n＜N₀The control device 180 is configured to control the closing of at least one resonator valve 171 proximate the closed end 177 of the cavity 174. During this stage, if the diesel engine 130 is in the loading process of increasing the rotation speed, the control device 180 is configured to control the plurality of resonant valves 171 to open sequentially in a direction away from the intake manifold 140. The control device 180 is configured to control the plurality of resonant valves 171 to close sequentially in a direction approaching the intake manifold 140 when the diesel engine 130 is in the unloading process of the reduction of the rotational speed.

If N is equal to N₀The control device 180 is configured to control both of the at least two resonance valves 171 in the opened state.

If N is present₀＜n≤N_maxThe control device 180 is configured to control the closing of at least one resonator valve 171 proximate the closed end 177 of the cavity 174. In this stage, if the diesel engine 130 is in the loading process of increasing the rotation speed, the control device 180Configured to control the plurality of resonance valves 171 to close in sequence in a direction approaching the intake manifold 140. The control means 180 is configured to control the at least two resonance valves 171 to open sequentially in a direction away from the intake manifold 140 if the diesel engine 130 is in the unloading process of the reduction of the rotational speed.

In the present embodiment, referring to fig. 6 for example, when the diesel engine 130 is in the loading process, the rotation speed thereof starts to increase from the idle rotation speed, and when the rotation speed thereof increases to the first rotation speed N₁And N is_min＜N₁＜N_maxThe control device 180 controls both the first resonance valve 172 and the second resonance valve 173 to be opened. Wherein N is₁May be with N₀Similar rotational speeds.

When the rotation speed of the diesel engine 130 is increased to the second rotation speed N₂And N is₁＜N₂≤N_maxThe control device 180 controls the first resonance valve 172 to be opened and controls the second resonance valve 173 to be closed.

When the rotation speed of the diesel engine 130 reaches the rated rotation speed N_maxAt this time, the control device 180 controls the first resonance valve 172 to be opened and controls the second resonance valve 173 to be closed.

When the diesel engine 130 is in the load shedding process, the rotation speed of the diesel engine starts to decrease from the rated rotation speed, and when the rotation speed of the diesel engine 130 decreases to a third rotation speed N₃And N is_min＜N₃＜N_maxThe control device 180 controls both the first resonance valve 172 and the second resonance valve 173 to be opened. Wherein N is₃May be with N₀Similar rotational speeds.

When the rotation speed of the diesel engine 130 is reduced to the fourth rotation speed N₄And N is₄＜N₃The control device 180 controls both the first resonant valve 172 and the second resonant valve 173 to be opened and closed. Wherein N is₄May be with N_minSimilar rotational speeds. Thereby fully utilizing the intake pressure fluctuation to accelerate the intake at a lower rotation speed.

The flows and steps described in all the preferred embodiments described above are only examples. Unless an adverse effect occurs, various processing operations may be performed in a different order from the order of the above-described flow. The above-mentioned steps of the flow can be added, combined or deleted according to the actual requirement.

Unless defined otherwise, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Features described herein in one embodiment may be applied to another embodiment, either alone or in combination with other features, unless the feature is otherwise inapplicable or otherwise stated in the other embodiment.

The present invention has been illustrated by the above embodiments, but it should be understood that the above embodiments are for illustrative and descriptive purposes only and are not intended to limit the invention to the scope of the described embodiments. Furthermore, it will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and that many variations and modifications may be made in accordance with the teachings of the present invention, which variations and modifications are within the scope of the present invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.