CN101302972A - Dimethyl ether engine split gear pump fuel supply system - Google Patents

Abstract

Dimethyl ether engine split gear pump fuel supply system belongs to the technical field of power machinery engineering, including: high pressure oil pump, driving wheel, transmission belt, driven wheel, transmission shaft, accumulator, gear pump, switch valve, dimethyl ether tank , Cooler, overflow valve, pressure gauge, coarse filter, fine filter. The invention utilizes the driving wheel installed at the front end of the dimethyl ether engine to drive the gear pump to run through the transmission belt to pressurize the liquid dimethyl ether. The gear pump is directly mechanically driven by the engine, avoiding the conversion link of mechanical energy-electrical energy-mechanical energy; the cooler cools and returns DME to keep the temperature of the DME tank lower than 40°C, ensuring sufficient power output by the DME engine. The dimethyl ether flow is adjusted in real time according to the engine speed to avoid energy waste; the gear pump has low cost, long life, low noise, and is easy to maintain and use.

Description

Dimethyl ether engine split gear pump fuel supply system

technical field

The invention relates to a dimethyl ether engine fuel supply system, in particular to a dimethyl ether engine split gear pump type fuel supply system, which belongs to the technical field of power machinery engineering.

Background technique

At normal temperature and pressure, dimethyl ether is gaseous and liquefied under 0.5MPa pressure. There are two types of supply systems used by DME engines: nitrogen pressurized type and electric pump type. In the existing technology, S.Kaji tani introduced the nitrogen pressurization used in the dimethyl ether engine in the article "Engine Performance and Exhaust Characteristics of Direct-injection Diesel Engine Operated with DME" (Society of Automotive Engineers paper, number: SAE Paper 972973) supply system. This kind of system has complicated structure and inconvenient application, and is especially unsuitable for vehicle DME engines. In the article "Study on Combustion and EmissionsCharacteristics of Turbocharged Engine Fuelled with Dimethyl Ether" (KSAE 2006, Vol.7, NO.6, P645~652), Wu Junhua introduced the electric pump supply system used in dimethyl ether engines. In this system, the electric pump is always in a full-load state, and the flow cannot be adjusted in real time according to the engine speed, so the energy consumption is high; at the same time, the electromagnetic coil of the electric pump is prone to heat, which causes the temperature of the dimethyl ether fuel to increase and the density to decrease, which affects the engine power. output. In addition, the electric pump has high cost, short life and high noise.

Contents of the invention

In order to overcome the deficiencies and defects in the prior art, the present invention provides a dimethyl ether engine split gear pump type fuel supply system, and the present invention is realized through the following technical solutions. The invention includes: high-pressure oil pump, driving wheel, transmission belt, front bearing, driven wheel, transmission shaft, rear bearing, accumulator, connecting flange, gear pump, first switch valve, dimethyl ether tank, second switch valve, Return pipe, cooler, overflow valve, first pressure gauge, inlet pipe, coarse filter, fine filter, second pressure gauge. The high pressure oil pump is driven by the engine. The driving wheel is installed at the front end of the engine, the driven wheel is connected with the driving wheel belt through the transmission belt, the driven wheel is installed on the transmission shaft, the gear pump is connected with the transmission shaft through the connecting flange, and the transmission shaft is supported by the front bearing and the rear bearing, which constitute the gear pump drive system. One end of the inlet pipe goes deep into the bottom of the dimethyl ether tank, the other end is connected to the inlet of the gear pump through the first on-off valve and the coarse filter, and the outlet of the gear pump is connected to the inlet of the high-pressure oil pump through the fine filter, and they constitute the inlet system. The outlet of the high-pressure oil pump is connected with the fuel injector installed on the engine. The return port of the high-pressure oil pump communicates with the dimethyl ether tank through the overflow valve, cooler, return pipe, and the second switch valve, and they constitute the return system. The first pressure gauge is placed on the pipeline between the first on-off valve and the coarse filter to display the pressure in the dimethyl ether tank. The second pressure gauge is installed on the return pipe between the return port of the fuel injection pump and the overflow valve to display the return pressure. The accumulator is placed on the pipeline between the inlet of the high-pressure oil pump and the fine filter to suppress pressure fluctuations in the pipeline.

When the engine is running, the driving wheel rotates, drives the driven wheel and the transmission shaft to rotate through the transmission belt, and the transmission shaft drives the gear pump to run through the connecting flange. The gear pump pressurizes the liquid dimethyl ether from the dimethyl ether tank and sprays it into the engine through the high-pressure oil pump. The dimethyl ether returned by the high-pressure oil pump passes through the overflow valve, the cooler, and the second on-off valve in sequence and enters the dimethyl ether tank. The overflow valve adjusts the return pressure of the high-pressure oil pump. In order to ensure that the dimethyl ether is in a liquid state in the high-pressure oil pump and make the engine run reliably, the return pressure is 1.5MPa-2.1MPa. The cooler cools and returns the dimethyl ether, so that the temperature of the dimethyl ether tank 13 is lower than 40° C. to ensure that the dimethyl ether engine outputs sufficient power.

Beneficial effects of the present invention: the present invention utilizes the driving wheel installed at the front end of the dimethyl ether engine to drive the gear pump through the transmission belt to pressurize the liquid dimethyl ether. The gear pump is directly mechanically driven by the engine, avoiding the conversion link of mechanical energy-electric energy-mechanical energy; the flow rate of dimethyl ether is adjusted in real time according to the speed of the engine to avoid energy waste; the gear pump is low in cost, long in life, low in noise, and easy to maintain and use; The cooler cools and returns the dimethyl ether, so that the temperature of the dimethyl ether tank is lower than 40°C, so as to ensure that the dimethyl ether engine outputs sufficient power.

Description of drawings

Fig. 1 is a schematic structural diagram of the system of the present invention.

In the figure, 1 engine, 2 high-pressure oil pump, 3 driving wheel, 4 transmission belt, 5 front bearing, 6 driven wheel, 7 transmission shaft, 8 rear bearing, 9 accumulator, 10 connecting flange, 11 gear pump, 12 first On-off valve, 13 DME tank, 14 second on-off valve, 15 return pipe, 16 cooler, 17 overflow valve, 18 first pressure gauge, 19 inlet pipe, 20 coarse filter, 21 fine filter, 22 second pressure gauge.

Detailed ways

The specific implementation of the present invention will be further described below in conjunction with the accompanying drawings.

As shown in Figure 1, the present invention includes: high-pressure oil pump 2, driving wheel 3, transmission belt 4, front bearing 5, driven wheel 6, transmission shaft 7, rear bearing 8, accumulator 9, coupling flange 10, gear pump 11 , the first on-off valve 12, the dimethyl ether tank 13, the second on-off valve 14, the return pipe 15, the cooler 16, the overflow valve 17, the first pressure gauge 18, the inlet pipe 19, the coarse filter 20, the fine filter 21 , The second pressure gauge 22. The high-pressure oil pump 2 is driven by the engine 1 . The driving wheel 3 is installed on the front end of the engine 1, the driven wheel 6 is connected with the belt of the driving wheel 3 through the transmission belt 4, the driven wheel 6 is mounted on the transmission shaft 7, the gear pump 11 is connected with the transmission shaft 7 through the connecting flange 10, and the transmission shaft 7 Supported by the front bearing 5 and the rear bearing 8, they constitute the gear pump drive system. One end of the inlet pipe 19 goes deep into the bottom of the dimethyl ether tank 13, and the other end is connected to the inlet of the gear pump 11 through the first on-off valve 12 and the coarse filter 20, and the outlet of the gear pump 11 is connected to the inlet of the high-pressure oil pump 2 through the fine filter 21. They constitute Inflow system. The outlet of the high-pressure oil pump 2 is connected with the fuel injector installed on the engine 1. The return port of the high-pressure oil pump 2 communicates with the dimethyl ether tank 13 through the overflow valve 17, the cooler 16, the return pipe 15, and the second switch valve 14, and they constitute a return system. The first pressure gauge 18 is placed on the pipeline between the first on-off valve 12 and the strainer 20 to display the pressure in the dimethyl ether tank 13 . The second pressure gauge 22 is installed on the return pipe 15 between the return port of the fuel injection pump 2 and the overflow valve 17, and displays the return pressure. The accumulator 9 is placed on the pipeline between the inlet of the high-pressure oil pump 2 and the fine filter 21 to suppress pressure fluctuations in the pipeline.

When the engine 1 is running, the driving wheel 3 rotates, and drives the driven wheel 6 and the transmission shaft 7 to rotate through the transmission belt 4, and the transmission shaft 7 drives the gear pump 11 to run through the connecting flange 10. The gear pump 11 pressurizes the liquid dimethyl ether from the dimethyl ether tank 13 and injects it into the engine 1 by the high-pressure oil pump 2 . The high-pressure oil pump 2 returns dimethyl ether to the dimethyl ether tank 13 through the overflow valve 17, the cooler 16, and the second switching valve 14 in sequence. The overflow valve 17 regulates the return pressure of the high-pressure oil pump 2. In order to ensure that the dimethyl ether is in a liquid state in the high-pressure oil pump 2 and make the engine run reliably, the return pressure is 1.5MPa-2.1MPa. The cooler 16 cools and returns the dimethyl ether, so that the temperature of the dimethyl ether tank 13 is lower than 40° C. to ensure that the dimethyl ether engine outputs sufficient power.

Claims (2)

1. A dimethyl ether engine split gear pump type fuel supply system, including: high pressure oil pump (2), driving wheel (3), transmission belt (4), front bearing (5), driven wheel (6), transmission shaft (7), rear bearing (8), accumulator (9), connecting flange (10), gear pump (11), first switch valve (12), dimethyl ether tank (13), second switch valve (14), return pipe (15), cooler (16), overflow valve (17), first pressure gauge (18), inlet pipe (19), coarse filter (20), fine filter (21), The second pressure gauge (22) is characterized in that: the high-pressure oil pump (2) is driven by the engine (1); the driving wheel (3) is installed on the front end of the engine (1), and the driven wheel (6) is connected to the driving wheel through the transmission belt (4) (3) Belt connection, the driven wheel (6) is installed on the transmission shaft (7), the gear pump (11) is connected to the transmission shaft (7) through the connecting flange (10), and the transmission shaft (7) is supported by the front bearing ( 5) supported by the rear bearing (8); one end of the inlet pipe (19) goes deep into the bottom of the dimethyl ether tank (13), and the other end passes through the first on-off valve (12), the coarse filter (20) and the gear pump (11) The inlet is connected, the outlet of the gear pump (11) is connected to the inlet of the high-pressure oil pump (2) through the fine filter (21); the outlet of the high-pressure oil pump (2) is connected to the injector installed on the engine (1), and the high-pressure oil pump (2) returns The port communicates with the dimethyl ether tank (13) through the overflow valve (17), the cooler (16), the return pipe (15), and the second on-off valve (14); the first pressure gauge (18) is placed on the first switch On the pipeline between the valve (12) and the strainer (20), the second pressure gauge (22) is installed on the return pipe (15) between the return port of the fuel injection pump (2) and the overflow valve (17). The energy device (9) is placed on the pipeline between the inlet of the high-pressure oil pump (2) and the fine filter (21). 2. The dimethyl ether engine split gear pump type fuel supply system according to claim 1, characterized in that the return pressure of the high-pressure oil pump (2) is 1.5MPa～2.1MPa; the dimethyl ether tank (13) The temperature is below 40°C.

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