Power system and engine cleaning method

Abstract

To provide a power system and an engine cleaning method capable of maintaining a state in which carbon hardly accumulates inside an engine and in an exhaust pipe. 【Solution means】The power system includes an engine, a power unit configured to be driven by the engine, and a gas supply unit configured to supply a cleaning gas containing hydrogen gas and oxygen gas. The gas supply unit is configured to continuously supply the cleaning gas to the air intake of the engine when the power unit is being driven by the engine. In the engine cleaning method, when the engine is driving the power unit, a cleaning gas containing hydrogen gas and oxygen gas is continuously supplied to the air intake of the engine.

Description

Technical Field

[0001] The present disclosure relates to a power system and an engine cleaning method.

Background Art

[0002] Engine cleaning methods are described in Patent Documents 1 and 2. In the engine cleaning method described in Patent Document 1, hydrogen gas is supplied into the combustion chamber of the engine. In the engine cleaning method described in Patent Document 2, a mixed gas of hydrogen gas and oxygen gas is supplied to the intake port of the engine. The engine cleaning methods described in Patent Documents 1 and 2 are intended to remove carbon deposited inside the engine and in the exhaust pipe.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] Even if carbon can be temporarily removed by implementing the engine cleaning methods described in Patent Documents 1 and 2, carbon will deposit again inside the engine and in the exhaust pipe as the engine is used. In one aspect of the present disclosure, it is preferable to provide a power system and an engine cleaning method capable of maintaining a state in which carbon hardly deposits inside the engine and in the exhaust pipe.

Means for Solving the Problems

[0005] One aspect of the present disclosure provides a power system including an engine, a power unit configured to be driven by the engine, and a gas supply unit configured to supply a cleaning gas containing hydrogen gas and oxygen gas. When the power unit is driven by the engine, the gas supply unit is configured to continuously supply the cleaning gas to an air intake of the engine. According to the power system which is one aspect of the present disclosure, it is possible to maintain a state in which carbon is less likely to accumulate inside the engine and in the exhaust pipe.

[0006] Another aspect of the present disclosure provides an engine cleaning method in which, when the engine is driving the power unit, a cleaning gas containing hydrogen gas and oxygen gas is continuously supplied to an air intake of the engine.

[0007] According to the engine cleaning method which is another aspect of the present disclosure, it is possible to maintain a state in which carbon is less likely to accumulate inside the engine and in the exhaust pipe. BRIEF DESCRIPTION OF THE DRAWINGS

[0008]

Figure 1

Figure 2

Figure 3

[0009] Exemplary embodiments of the present disclosure will be described with reference to the drawings. <First Embodiment> 1. Configuration of Power System 1 The configuration of the power system 1 will be described with reference to FIG. 1. The power system 1 is a power source for, for example, a moving body, a generator, a construction machine, etc. Examples of the moving body include a ship, a vehicle, an aircraft, etc. The power system 1 is mounted on, for example, a moving body, a generator, a construction machine, etc.

[0010] The power system 1 includes an engine 3, a power unit 5, a gas supply unit 7, an exhaust pipe 9, and a generator 11. Examples of the engine 3 include a gasoline engine, a diesel engine, a gas engine, and the like.

[0011] The power unit 5 is a member configured to be driven by the engine 3. Examples of the power unit 5 include a ship's propeller, vehicle wheels, and the like. For example, the power unit 5 can be switched between a state of being connected to the engine 3 and a state of being disconnected from the engine 3. When the power unit 5 is connected to the engine 3, it is driven by the engine 3. When the power unit 5 is disconnected from the engine 3, even if the engine 3 is operating, it is not driven by the engine 3.

[0012] The gas supply unit 7 is a member configured to supply a cleaning gas containing hydrogen gas and oxygen gas to the air intake 8 of the engine 3. When the power unit 5 is being driven by the engine 3, the gas supply unit 7 continuously supplies the cleaning gas to the air intake 8.

[0013] When the power unit 5 is being driven by the engine 3, for example, it is when a moving body equipped with the power system 1 is moving, when the moving body equipped with the power system 1 is stopped but the engine 3 is running, when a generator equipped with the power system 1 is generating electricity, or when a construction machine equipped with the power system 1 is operating. When the moving body is moving, for example, it is when a ship is sailing or when a vehicle is traveling.

[0014] The gas supply unit 7 includes a gas generator 21, a battery 23, and a main switch 25. The gas generator 21 is a device that electrolyzes an aqueous electrolyte solution in which an electrolyte is dissolved to generate a cleaning gas containing hydrogen gas and oxygen gas. Examples of the electrolyte include sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium sulfate, sodium hydrogen carbonate, and the like. The concentration of the electrolyte in the aqueous electrolyte solution is, for example, 0.1 to 10% by mass, and preferably 0.5 to 5% by mass.

[0015] Examples of commercially available products of the gas generator 21 include the hybrid fuel reduction device HFR-3000 (manufactured by Eight Factory Co., Ltd., registered trademark), etc. Also, as the gas generator 21, the "cleaning gas generator 2" described in paragraphs 0026 to 0035 of the specification of Patent Document 2 and FIG. 2 can be used.

[0016] The cleaning gas is, for example, a gas mainly composed of hydrogen gas and oxygen gas. For example, in the cleaning gas, the volume ratio of hydrogen gas to oxygen gas is 2:1. For example, the cleaning gas, excluding impurities, does not contain components other than hydrogen gas and oxygen gas. Examples of the impurities include water vapor, trace components in the atmosphere, etc. The cleaning gas, for example, in addition to hydrogen gas and oxygen gas, contains a part or all of O - (monovalent oxygen radical), O 2- (divalent oxygen radical), OH - (hydrogen oxygen radical), and O 3 (ozone).

[0017] The cleaning gas generated by the gas generator 21 is supplied to the air intake 8. The air intake 8 inhales the cleaning gas together with the air. For example, the cleaning gas is naturally aspirated from the air intake 8. The greater the intake amount of air in the air intake 8, the greater the amount of cleaning gas inhaled into the air intake 8.

[0018] The battery 23 supplies power for electrolysis to the gas generator 21. The main switch 25 turns on / off the electrical connection between the battery 23 and the gas generator 21. The main switch 25 is on when the engine 3 is running. The main switch 25 is off when the engine 3 is stopped.

[0019] The exhaust pipe 9 exhausts the exhaust gas generated by the engine 3. The generator 11 charges the battery 23 using the driving force of the engine 3. The voltage supplied by the battery 23 to the gas generator 21 increases as the rotational speed of the engine 3 increases. For example, when the rotational speed of the engine 3 is 600 rpm, the voltage supplied by the battery 23 to the gas generator 21 is 24V. Also, for example, when the rotational speed of the engine 3 is 3000 rpm, the voltage supplied by the battery 23 to the gas generator 21 is 30V. Therefore, the gas supply unit 7 supplies more cleaning gas to the air intake 8 as the rotational speed of the engine 3 increases.

[0020] 2. Engine cleaning method executed by the power system 1 When the engine 3 is driving the power unit 5, the power system 1 continuously supplies cleaning gas to the air intake 8 of the engine 3.

[0021] When the engine 3 is driving the power unit 5 means, for example, when the moving body equipped with the power system 1 is moving, when the generator equipped with the power system 1 is generating electricity, when the construction machine equipped with the power system 1 is operating. When the moving body is moving means, for example, when a ship is sailing, when a vehicle is running.

[0022] The greater the intake amount of air at the air intake 8, the greater the amount of cleaning gas inhaled into the air intake 8. The gas supply unit 7 supplies more cleaning gas to the air intake 8 as the rotational speed of the engine 3 increases.

[0023] 3. Effects of the power system 1 and the engine cleaning method (1A) When the power unit 5 is driven by the engine 3, the power system 1 continuously supplies the cleaning gas to the air intake 8. Therefore, it is possible to maintain a state in which carbon is less likely to accumulate inside the engine 3 and in the exhaust pipe 9.

[0024] (1B) In the engine cleaning method executed by the power system 1, when the engine 3 is driving the power unit 5, the cleaning gas is continuously supplied to the air intake 8 of the engine 3. Therefore, it is possible to maintain a state in which carbon is less likely to accumulate inside the engine 3 and in the exhaust pipe 9.

[0025] (1C) In the power system 1 and the engine cleaning method, the greater the intake amount of air at the air intake 8, the greater the amount of cleaning gas inhaled into the air intake 8. Therefore, even when the rotational speed of the engine 3 changes and the intake amount of air at the air intake 8 changes, the concentration of the cleaning gas inside the engine 3 can be maintained within an appropriate range. The appropriate range is a range in which the adhesion of carbon to the inside of the engine 3 and the exhaust pipe 9 can be suppressed and the load on the engine 3 is reduced.

[0026] (1D) In the power system 1 and the engine cleaning method, the higher the rotational speed of the engine 3, the more the cleaning gas is supplied to the air intake 8. Therefore, even when the rotational speed of the engine 3 changes and the intake amount of air at the air intake 8 changes, the concentration of the cleaning gas inside the engine 3 can be maintained within an appropriate range. The appropriate range is a range in which the adhesion of carbon to the inside of the engine 3 and the exhaust pipe 9 can be suppressed and the load on the engine 3 is reduced.

[0027] (1E) The power system 1 can reduce the amount of fuel consumed by the engine 3 compared to the case where the cleaning gas is not supplied to the air intake 8. The reason is presumably that the hydrogen gas contained in the cleaning gas acts as fuel for the engine 3.

[0028] (1F) The power system 1 supplies power to the gas generator 21 by the generator 11. Therefore, it is not necessary to provide a dedicated power source for the gas generator 21. (1G) In the power system 1 and the engine cleaning method, the amount of cleaning gas supplied to the engine 3 per unit time may be small compared to the engine cleaning methods described in Patent Documents 1 and 2. Therefore, the load on the engine 3 is small, and the life of the engine 3 can be extended.

[0029] 4. Example 1 (1) Configuration of the power system 1 in Example 1 A power system 1 having the configuration described in "1. Configuration of the power system 1" was prepared. In this example, the power system 1 was installed on a ship. The power system 1 was the power source of the ship. The ship was a 7.3-ton EP ship. The power unit 5 was the screw of the ship. The engine 3 was a Yanmar 6CA-GT. The gas generation device 21 was a hybrid fuel reduction device HFR-3000 (manufactured by Eight Factory Co., Ltd.). The cleaning gas was a gas mainly composed of hydrogen gas and oxygen gas. In the cleaning gas, the volume ratio of hydrogen gas to oxygen gas was 2:1. The cleaning gas contained, in addition to hydrogen gas and oxygen gas, O - (oxygen radical monovalent), O 2- (oxygen radical divalent), OH - (hydrogen oxygen radical), and O 3 (ozone).

[0030] (2) Measurement of fuel consumption The ship was operated under the following conditions A and B, respectively. Condition A: During the operation of the ship, the cleaning gas was continuously supplied to the air intake 8 at all times. The greater the intake amount of air at the air intake 8, the greater the amount of cleaning gas inhaled into the air intake 8. Also, the gas supply unit 7 supplied more cleaning gas to the air intake 8 as the rotational speed of the engine 3 was higher. The relationship between the rotational speed of the engine 3 and the voltage V supplied by the battery 23 to the gas generation device 21 was as shown in Table 1.

[0031]

Table 1

[0032] Condition B: During the operation of the ship, no cleaning gas was supplied to the air intake 8 at all. Under Conditions A and B, the fuel consumption per hour of ship operation (hereinafter referred to as fuel efficiency) was calculated. The results are shown in Table 2. Note that the measurement of fuel efficiency was performed twice for each of Conditions A and B.

[0033]

Table 2

[0034] The fuel efficiency under Condition A was significantly reduced compared to that under Condition B.

[0035] 5. Example 2 (1) Configuration of the power system 1 in Example 2 A power system 1 having the configuration described in the above “1. Configuration of the power system 1” was prepared. In this example, the power system 1 was mounted on a diesel generator. The power system 1 was the power source of the diesel generator. The engine 3 was a diesel engine (manufactured by Yamaha, model number: 4TNE88 - RAG2). The gas generation device 21 was a hybrid fuel reduction device HFR - 3000 (manufactured by Eight Factory Co., Ltd.). The cleaning gas was a gas mainly composed of hydrogen gas and oxygen gas. In the cleaning gas, the volume ratio of hydrogen gas to oxygen gas was 2:1. The cleaning gas contained, in addition to hydrogen gas and oxygen gas, O - (oxygen radical monovalent), O 2- (oxygen radical divalent), OH - (hydroxyl radical), and O 3 (ozone).

[0036] (2) Operation of the diesel generator The diesel generator was operated daily for 7 days. On the first day, the diesel generator was continuously operated for 2 hours. On the second to seventh days, the diesel generator was continuously operated for 1 hour each day. During the operation of the diesel generator, the cleaning gas was constantly and continuously supplied to the air intake 8. After the operation on the first day, soot fell in pieces from the injector of the engine 3.

[0037] At the end of the operation on the first day, at the end of the operation on the fourth day, and at the end of the operation on the seventh day, the upper surface of the piston, the upper part of the cylinder, and the cylinder valve surface of the engine 3 were observed respectively. From the observation results, it was confirmed that the carbon deposition in the engine 3 decreased. The reason for the decrease in carbon deposition in the above test is speculated as follows.

[0038] The carbon mentioned here is carbon atoms generated by the decomposition of hydrocarbons, which are compounds of carbon and hydrogen, or soot formed by the aggregation of carbon atoms. Since substances that appear black are considered aggregates of carbon, those released into the air or adhering to the wall surface are referred to as soot. Since the size (i.e., diameter) of carbon atoms is shorter than the wavelength of visible light, they cannot be recognized by the naked eye even when released into the air. However, when a plurality of these carbon atoms aggregate and the size of the aggregated soot becomes equal to or greater than the wavelength of visible light, it can be recognized by the naked eye and appears as black smoke.

[0039] Similarly, when soot adheres to the combustion chamber or the exhaust pipe wall surface of the engine 3, it becomes soot that appears black to the naked eye when it has a size above a certain level, similar to soot formed by the aggregation of carbon in the air.

[0040] On the other hand, in the power system 1, it is presumed that the cleaning gas generated by the electrolysis of water contains some or all of the following radicals (i) to (iv) and ozone. (i)O - (monovalent oxygen radical) (ii)O 2- (divalent oxygen radical) (iii)OH- (Hydrogen peroxide radical) (iv)O 3 (Ozone)

[0041] O - (Monovalent oxygen radical) has high reactivity towards reactions and may combine with carbon contained in soot to form CO. Due to this reaction, soot in the air or on the wall surface will decrease. At this time, the generated CO (carbon monoxide) is a colorless and transparent gas at normal temperature and pressure, so it is difficult to be recognized by the naked eye even when discharged. Therefore, although the carbon itself has not disappeared, only the decrease in soot is recognized because it is discharged in a changed form.

[0042] O 2- (Divalent oxygen radical) may react with O - (Monovalent oxygen radical) to become CO 2 (Carbon dioxide). CO 2 (Carbon dioxide) is also a colorless and transparent gas at normal temperature and pressure, so it is difficult to be recognized by the naked eye even when discharged. Furthermore, since CO (carbon monoxide) is non-polar, it is insoluble in water which is a polar solvent, but CO 2 (Carbon dioxide) is soluble in water, so it is even more difficult to recognize the discharge because it comes out contained in the water in the exhaust gas.

[0043] O 2- (Divalent oxygen radical) has even higher reactivity towards reactions compared to O - (Monovalent oxygen radical), and may combine with carbon contained in soot to form CO. The reason for recognizing that the soot has decreased due to this reaction is the same as in the case of O - (Monovalent oxygen radical).

[0044] OH - (Hydrogen radical) has high activity and reacts as follows, and two OH - (Hydrogen radicals) combine to form H 2 O 2 (Hydrogen peroxide). OH - + OH - = H2 O 2 However, H 2 O 2 (hydrogen peroxide) is unstable and thus reacts as follows to decompose into water and O - (monovalent oxygen radical). The O - (monovalent oxygen radical) generated thereby will also reduce soot by the same process as described above. H 2 O 2 = H 2 0 + O -

[0045] O 3 (ozone) also has high activity and thus may react with the carbon in the soot, contributing to soot reduction in the same process as O - (monovalent oxygen radical), O 2- (divalent oxygen radical), or OH - (hydrogen radical). However, O 3 (ozone) has the property of reacting and decomposing as follows when the temperature reaches about 400°C or higher. O 3 = O 2 + O -

[0046] Therefore, when the cleaning gas is introduced into the air intake 8 of the engine 3 as in the present disclosure, O 3 (ozone) is likely to be decomposed by entering the engine combustion chamber. Thus, it is presumed that the reduction of soot is likely due to the action of O 3 (monovalent oxygen radical) after decomposition rather than O - (ozone) itself.

[0047] Next, in the case of Example 1, the reason why the fuel consumption could be reduced under Condition A is presumed as follows. The reduction of the above-mentioned soot targets the soot present in the exhaust of the engine 3, whereas the improvement in fuel consumption targets the reaction with the fuel in the combustion process of the engine 3.

[0048] Here, when discussing fuel efficiency, the efficiency of engine 3 will be described. The efficiency of engine 3 is the ratio of the energy obtained from engine 3 to the energy of the fuel input. On the other hand, the fuel efficiency is the ratio of the work obtained to the cost of the fuel input. Therefore, an improvement in fuel efficiency can be regarded as an improvement in efficiency. The formula for defining the efficiency of engine 3 is described below. Efficiency of engine 3 = Combustion efficiency × Mechanical conversion efficiency

[0049] Here, the combustion efficiency is the ratio of the fuel that contributed to combustion, i.e., the oxidation reaction, among the fuel input. The mechanical conversion efficiency is the ratio of the thermal energy generated by the combustion of the fuel that the mechanism of engine 3 could convert into kinetic energy.

[0050] Therefore, the factor for improving efficiency is either an improvement in combustion efficiency or an improvement in mechanical conversion efficiency. The effect according to the present disclosure is considered unlikely to affect the mechanism of engine 3 and is considered to be due to an improvement in the former combustion efficiency. Combustion is the reaction of C (carbon) or H (hydrogen) in the fuel with O (oxygen), and an increase in this ratio is an improvement in combustion efficiency. The fuel components that could not contribute to the reaction in the combustion of engine 3 will go out into the exhaust as HC (hydrocarbon).

[0051] Here, some or all of the radicals (i) to (iv) and ozone generated by the electrolysis of water using the power system 1 contribute. The radicals (i) to (iv) and ozone all promote the oxidation reaction, and the reaction described by the reduction of soot is the basic mechanism.

[0052] Here, the aforementioned reduction of soot targets the soot present in the exhaust of the engine 3, while the improvement in fuel efficiency targets the reaction with fuel in the combustion process of the engine 3. That is, the carbon molecules contained in the gas in the combustion chamber generated by the decomposition of the vaporized fuel are the target. Furthermore, the hydrogen contained in the gas in the combustion chamber generated by the decomposition of the vaporized fuel is also the target. Therefore, it is considered that the promotion of this oxidation reaction, that is, the ratio of the fuel that can effectively contribute to the reaction in the input fuel = the combustion efficiency is improved, thereby improving the fuel efficiency.

[0053] 6. Example 3 (1) Configuration of the power system 1 in Example 3 A power system 1 having the configuration described in "1. Configuration of the power system 1" was prepared. In this example, the power system 1 was mounted on a vehicle. The power system 1 was the power source of the vehicle. The power unit 5 was the vehicle's wheels. The engine 3 was a diesel engine (manufactured by Nissan, model number: KC-CD45). The displacement of the engine 3 was 12500 CC.

[0054] The gas generation device 21 was a hybrid fuel reduction device HFR-3000 (manufactured by Eight Factory Co., Ltd.). The cleaning gas was a gas mainly composed of hydrogen gas and oxygen gas. In the cleaning gas, the volume ratio of hydrogen gas to oxygen gas was 2:1. The cleaning gas contained, in addition to hydrogen gas and oxygen gas, O - (oxygen radical monovalent), O 2- (oxygen radical divalent), OH - (hydroxyl radical), and O 3 (ozone).

[0055] (2) Operation of the vehicle The vehicle was operated daily for four days. On the first day, no cleaning gas was supplied to the air intake 8 during the operation of the vehicle. On the second to fourth days, cleaning gas was continuously supplied to the air intake 8 at all times during the operation of the vehicle. The greater the intake of air at the air intake 8, the greater the amount of cleaning gas inhaled into the air intake 8. Also, the gas supply unit 7 supplied more cleaning gas to the air intake 8 as the engine 3 had a higher rotational speed.

[0056] For each day, the daily driving distance of the vehicle, the daily consumption of light oil, and the driving distance per liter of light oil are shown in Table 3.

[0057]

Table 3

[0058] As shown in Table 3, on the second to fourth days when cleaning gas was continuously supplied to the air intake 8, the driving distance per liter of light oil was significantly longer than that on the first day when no cleaning gas was supplied to the air intake 8.

[0059] Before the operation on the first day, the soot discharged from the exhaust pipe 9 was collected on a gray cloth. The cloth is shown in Figure 2. After the operation on the fourth day, the soot discharged from the exhaust pipe 9 was collected on a gray cloth. The cloth is shown in Figure 3. Before the operation on the first day, there was a lot of soot discharged from the exhaust pipe 9. After the operation on the fourth day, the soot discharged from the exhaust pipe 9 had significantly decreased.

[0060] <Other Embodiments> As described above, the embodiments of the present disclosure have been described, but the present disclosure is not limited to the above-described embodiments and can be implemented with various modifications.

[0061] (1) In each of the above embodiments, the functions of one component may be shared among a plurality of components, or the functions of a plurality of components may be performed by one component. Also, a part of the configuration of each of the above embodiments may be omitted. Further, at least a part of the configuration of each of the above embodiments may be added to, replaced with, etc., the configuration of other above embodiments.

[0062] (2) In addition to the power system 1 described above, the present disclosure can also be realized in various forms such as a higher-level system having the power system 1 as a component, a control method of the power system 1, a method for improving the fuel efficiency of an engine, etc.

Description of Reference Numerals

[0063] 1... Power system, 3... Engine, 5... Power unit, 7... Gas supply unit, 8... Air intake, 9... Exhaust pipe, 11... Generator, 21... Gas generator, 23... Battery, 25... Main switch

Claims

1. The engine, a power unit configured to be driven by the engine; a gas supply configured to supply a cleaning gas including hydrogen gas, oxygen gas, oxygen radicals, oxygen-hydrogen radicals, and ozone; A generator configured to output a voltage according to the engine speed; Equipped with the gas supply unit is configured to receive power from the generator and generate an amount of the cleaning gas in response to the voltage supplied thereto, and is configured to continuously supply the cleaning gas to an air intake of the engine whenever the power unit is driven by the engine; Power system.

2. 2. The power system of claim 1, The greater the amount of air suctioned into the air intake, the greater the amount of cleaning gas suctioned into the air intake. Power system.

3. 3. The power system according to claim 1 or 2, The gas supply unit supplies a larger amount of the cleaning gas as the engine speed increases. Power system.

4. A method for washing an engine, comprising: receiving a supply of electric power from a generator configured to output a voltage corresponding to the engine speed, thereby generating a cleaning gas in an amount corresponding to the voltage, the cleaning gas including hydrogen gas, oxygen gas, oxygen radicals, oxygen-hydrogen radicals, and ozone; continuously supplying said scrubbing gas to an air intake of said engine whenever said engine is powered; An engine cleaning method.

5. 5. The engine washing method according to claim 4, Even if the amount of air suctioned into the air intake changes, the concentration of the cleaning gas sucked into the air intake is maintained within a predetermined range. How to wash an engine.

6. The engine washing method according to claim 4 or 5, The higher the engine speed, the more cleaning gas is supplied. How to wash an engine.

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