KR-20260062592-A - Liquid fuel supply system and Engine

KR20260062592AKR 20260062592 AKR20260062592 AKR 20260062592AKR-20260062592-A

Abstract

A liquid fuel supply system comprising: a high-pressure pump that compresses fuel and supplies it as high-pressure fuel; a diesel injector that receives and injects the high-pressure fuel; a high-pressure fuel supply pipe connecting the high-pressure pump and the diesel injector; a first solenoid valve provided in the high-pressure fuel supply pipe to regulate the amount of high-pressure fuel supplied to the diesel injector; a drain line located upstream of the first solenoid valve; a second solenoid valve that selectively opens and closes the drain line; and a control unit that controls the first solenoid valve and the second solenoid valve.

Inventors

유영수
박현춘

Assignees

에이치디현대중공업 주식회사

Dates

Publication Date: 20260507
Application Date: 20241029

Claims (12)

A high-pressure pump that compresses fuel and supplies it as high-pressure fuel; A diesel injector that receives and injects the above-mentioned high-pressure fuel; A high-pressure fuel supply pipe connecting the above-mentioned high-pressure pump and the above-mentioned diesel injector; A first solenoid valve provided in the high-pressure fuel supply pipe to regulate the amount of high-pressure fuel supplied to the diesel injector; A drain line located upstream of the first solenoid valve; A second solenoid valve for selectively opening and closing the drain line; and A liquid fuel supply system comprising a control unit that controls the first solenoid valve and the second solenoid valve.
In paragraph 1, The above control unit A liquid fuel supply system characterized by performing single injection of diesel fuel into the diesel injector by opening the first solenoid while the second solenoid is closed.
In paragraph 2, The above control unit A liquid fuel supply system characterized by opening the second solenoid valve after the above diesel single injection to remove residual fuel in the high-pressure fuel supply pipe.
In paragraph 3, The above control unit A liquid fuel supply system characterized by closing the first solenoid valve at a time equal to or later than the opening time of the second solenoid valve after the diesel single injection.
In paragraph 1, A liquid fuel supply system characterized by including a pressure sensor located between the above-mentioned diesel injector and the above-mentioned first solenoid valve.
In paragraph 1, A liquid fuel supply system characterized in that the above-described diesel injector is a mechanical injector that opens and closes by the pressure of high-pressure fuel supplied through the above-described high-pressure fuel supply pipe.
An engine comprising a liquid fuel supply system of any one of claims 1 to 6.
A step of generating high-pressure fuel by compressing liquid fuel in a high-pressure pump; A step of supplying the high-pressure fuel to the diesel injector by opening a first solenoid valve of a high-pressure fuel supply pipe that supplies the high-pressure fuel to the diesel injector; and The method includes the step of opening a second solenoid valve of a drain pipe branched from a high-pressure fuel supply pipe connecting a high-pressure pump and a diesel injector to discharge residual fuel from the high-pressure pipe. A liquid fuel supply system control method characterized in that the drain pipe is connected to the high-pressure fuel supply pipe at the upstream end of the first solenoid valve.
In paragraph 8, The step of supplying the high-pressure fuel to the diesel injector is performed while the second solenoid valve is closed, and A liquid fuel supply system control method characterized by including the step of closing the first solenoid valve after the step of supplying the high-pressure fuel to the diesel injector.
In Paragraph 9, A liquid fuel supply system control method characterized in that the step of closing the first solenoid valve is performed simultaneously with the step of discharging residual fuel or later than the step of discharging residual fuel.
In paragraph 8, A liquid fuel supply system control method characterized by the step of supplying the high-pressure fuel to the diesel injector being performed in milliseconds, thereby injecting the high-pressure fuel through the diesel injector.
An engine control method comprising a method for controlling a liquid fuel supply system according to any one of claims 8 to 11.

Description

Liquid fuel supply system and Engine The present invention relates to a liquid fuel supply system including a mechanical diesel injector and an engine including the same. Generally, ships obtain propulsion for their hulls by using one of the following: a diesel engine that generates driving force using diesel oil, a gas engine that generates driving force using gas such as LNG, or a dual-fuel engine that generates driving force using a mixture of diesel oil and gas. The dual-fuel engine system has a gas fuel operating mode using gas fuel and a liquid fuel operating mode using liquid fuel. Liquid fuel is injected into the combustion chamber by injectors equipped in each cylinder head, and gas fuel is distributed from the main feed pipe to the distribution pipes for each cylinder and then injected into the cylinder head through the Gas Admission Valve (GAV). Unlike gasoline engines, which ignite fuel with a spark plug, dual-fuel engine systems are based on diesel engines that induce spontaneous ignition by compressing the intake air to high temperature and pressure. However, gaseous fuels such as natural gas have low flash points but high spontaneous ignition temperatures of around 550°C, making spontaneous ignition difficult. A dual-fuel engine system can perform pilot injection using a diesel injector that injects liquid diesel fuel to assist in the ignition of gaseous fuel. During pilot injection, in gaseous fuel operation mode, a small amount of pilot fuel (diesel) is injected through the diesel injector immediately before injecting the main fuel (gaseous fuel) to induce stable spontaneous ignition of the gaseous fuel. Diesel injectors generally use a mechanical method that utilizes the increase in internal pressure. However, mechanical injectors have the disadvantage of high manufacturing costs due to the complex arrangement of many components, such as high-speed motors, inverters, camshafts, high-pressure pumps (plungers), high-pressure fuel supply pipes, fuel valves, and nozzles. In addition, the mechanical method of transmitting power to a high-pressure pump via a high-speed motor and inverter for injection has the problem of difficulty in single-injection (one-shot injection) and injection volume control due to the inability to control motor rotation. Figure 1 is a conceptual diagram of a marine engine of the present invention. Figure 2 is a conceptual diagram of a fuel supply system of a conventional mechanical diesel injector. FIG. 3 is a conceptual diagram according to one embodiment of the fuel supply system of a diesel injector of the present invention. FIG. 4 is a drawing illustrating a fuel single injection sun according to the embodiment of FIG. 3. FIG. 5 is a conceptual diagram according to another embodiment of the fuel supply system of a diesel injector of the present invention. FIG. 6 is a drawing illustrating a fuel single injection sun according to the embodiment of FIG. 5. Hereinafter, embodiments disclosed in this specification will be described in detail with reference to the attached drawings. Identical or similar components regardless of drawing symbols will be assigned the same reference number, and redundant descriptions thereof will be omitted. The suffixes "module" and "part" used for components in the following description are assigned or used interchangeably solely for the ease of drafting the specification and do not inherently possess distinct meanings or roles. Furthermore, in describing embodiments disclosed in this specification, if it is determined that a detailed description of related prior art could obscure the essence of the embodiments disclosed in this specification, such detailed description will be omitted. Additionally, the attached drawings are intended only to facilitate understanding of the embodiments disclosed in this specification; the technical concept disclosed in this specification is not limited by the attached drawings, and it should be understood that they include all modifications, equivalents, and substitutions that fall within the spirit and technical scope of the present invention. Terms including ordinal numbers, such as first, second, etc., may be used to describe various components, but said components are not limited by said terms. These terms are used solely for the purpose of distinguishing one component from another. When it is stated that one component is "connected" or "connected" to another component, it should be understood that while it may be directly connected or connected to that other component, there may also be other components in between. On the other hand, when it is stated that one component is "directly connected" or "directly connected" to another component, it should be understood that there are no other components in between. A singular expression includes a plural expression unless the context clearly indicates otherwise. In this application, terms such as “comprising” or “having” are intended to specify the existence o