Process for converting diesel internal combustion engine vehicles to a dual-fuel gas version with optimization of the gas percentage

Abstract

Method for converting diesel internal combustion engine vehicles to a dual-fuel gas version with optimized gas percentage. The invention relates to the field of converting internal combustion engine vehicles to a dual-fuel gas version in the case of turbocharged diesel vehicles. The method incorporates the elimination of turbocharging (T) or the reduction of turbocharging pressure (T) compared to the original configuration. The object of the invention is, by accepting a loss of engine boost (M), to reduce the combustion compression ratio and thus allow the injection of a larger quantity of gas while remaining below the knock limit. The gas is methane rather than butane, propane, or a mixture of the two such as LPG (Liquefied Petroleum Gas). Figure to be published with the abstract: Fig. 2.

Description

Title of the invention: Method for converting diesel internal combustion engine vehicles to a dual-fuel gas version with optimization of the gas percentage

[0001] FIELD OF THE INVENTION TO WHICH THE INVENTION RELATES

[0002] The invention relates to the field of conversions of internal combustion engine vehicles to a dual-fuel gas version.

[0003] This involves converting a thermal vehicle, a fleet of thermal vehicles, or a fleet of thermal vehicles, vehicles already originally put into circulation with thermal engines, to a dual-fuel gas engine and optimizing the percentage of gas relative to the original fuel. EARLIER ART

[0004] It is common to convert internal combustion engine vehicles to dual-fuel gas, including older gasoline vehicles operating with indirect gasoline injection.

[0005] In this context, the bi-fuel gas operating mode can be 100% gas, but according to the embodiments, once a certain temperature of the engine is reached, and in particular of its cooling water, to vaporize the gas.

[0006] In the context of gasoline engines with direct injection in each cylinder, it is common to retain around 15% gasoline not for physico-chemical reasons but to cool the injectors which, in the absence of the original fuel, would overheat and deteriorate.

[0007] In the context of diesel engines, in the absence of spark plugs, a direct injection of a minimum of diesel is necessary to initiate the combustion of the two fuels, namely the original fuel diesel and the gas.

[0008] In fact, in terms of fuel consumption and emissions, the conversion of a diesel vehicle to gas is all the more relevant as the proportion of gas is high and hardly bears comparison with the conversion to gas in gasoline injection, in particular in indirect injection.

[0009] BRIEF DESCRIPTION OF THE INVENTION

[0010] The method for converting vehicles already in circulation equipped with a diesel internal combustion engine to a dual-fuel gas version with optimized gas percentage according to the invention relates to turbocharged diesel internal combustion engines and consists at least of adding a second tank with its gas inlet and filler neck in addition to the original tank with its fuel inlet and filler neck Originally, it consists at least of adding an injection system with its own electronic control unit and injectors for gas in addition to the original injection system with the original electronic injection control unit and its injectors for the original fuel, as well as removing turbo boosting or reducing turbo boost pressure compared to the original configuration.

[0011] Advantageously, according to one embodiment, the reduction of the turbo boost pressure compared to the original configuration is achieved by a physical adjustment of the turbo boost pressure which is carried out at the level of the wastegate.

[0012] Advantageously, according to one embodiment, the reduction of the turbo boost pressure compared to the original configuration is achieved by downloading an engine control software version onto a retained engine control computer by programming a lower turbo boost pressure.

[0013] Advantageously, according to one embodiment, the original electronic injection computer uses the measurement of the turbo boost pressure by a pressure sensor and the reduction of the turbo boost pressure compared to the original configuration is achieved by tricking the original electronic injection computer by replacing the original pressure sensor with a pressure sensor giving a turbo boost pressure measurement higher than the pressure actually measured.

[0014] Advantageously, according to one embodiment, the original electronic injection control unit uses the measurement of the turbo boost pressure by a pressure sensor and the reduction of the turbo boost pressure compared to the original configuration is carried out by the electronic gas injection control unit by tricking the original electronic injection control unit by intercepting the original pressure measurement signal and modulating it to give a turbo boost pressure measurement signal corresponding to a pressure higher than the pressure actually measured.

[0015] Advantageously in terms of power, the decrease in boost pressure is compensated to within 10% by the additional power provided by the injection of gas in addition to the injection of diesel fuel.

[0016] Advantageously, the gas is methane rather than butane, propane or a mixture of the two such as LPG (Liquefied Petroleum Gas).

[0017] Advantageously, the conversion process involves adding a knock sensor to the engine and the gas injection system computer is connected to this knock sensor.

[0018] Advantageously, the conversion process includes the addition of a sensor The temperature on the engine exhaust line and the gas injection system computer is connected to this temperature sensor.

[0019] Advantageously, the conversion method involves adding an oxygen sensor to the engine's exhaust line, and the gas injection system's computer is connected to this oxygen sensor. Brief description of the drawings

[0020] Other features and advantages of the invention will become apparent from the following detailed description, for the understanding of which reference should be made to the accompanying drawings.

[0021] [Fig-1] shows an embodiment of a conversion of a vehicle into a bicar gas injection with in particular the addition of a second tank with its supply chute and its gas filling orifice and the addition of an injection system with its own electronic computer and its injectors for the gas.

[0022] [Fig.2] shows a vehicle with its engine and in particular its turbocharger mentation. DETAILED DESCRIPTION OF THE INVENTION

[0023] The method for converting vehicles (V) already in circulation comprising a diesel internal combustion engine (M) to a dual-fuel gas version with optimization of the gas percentage according to the invention relates to diesel internal combustion engines (M) supercharged by a turbocharger (T) and consists at least of adding a second tank (R2) with its gas supply chute and its gas filling port (O2) in addition to the original tank (RI) with its supply chute and its gas filling port (O1) for the original fuel, consists at least of adding an injection system with its own electronic control unit (C2) and its injectors (12) for the gas in addition to the original injection system with the original electronic injection control unit (C1) and its injectors (II) for the original fuel,

[0024] Fig. 1 illustrates the classic implementation of the conversion of a vehicle with an internal combustion engine already in circulation by a dual-fuel gas version consisting at least of the addition of a second tank (R2) with its gas supply chute and its gas filling orifice (02) in addition to the original tank (RI) with its original fuel supply chute and its original fuel filling orifice (01) and the addition of an injection system with its own electronic control unit (C2) and its injectors (12) for gas in addition to the original injection system with the original electronic injection control unit (C1) and its injectors (II) for the original fuel.

[0025] Advantageously, a polyvalve (PV) is associated with the gas reservoir (R2) in particular to ensure a safety valve function.

[0026] Conventionally, a vaporizer-regulator (VD) is added to convert the liquid LPG from the gas tank (R2) into a gas for the gas injectors (12), as well as in the case of low-temperature natural gas. To this end, the vaporizer-regulator (VD) utilizes the engine's heat by intercepting the engine's cooling circuit via water-conducting pipes (CE).

[0027] The method according to the invention includes the suppression of turbocharging (T) or the reduction of turbocharging pressure (T) compared to the original configuration.

[0028] The object of the invention is, by accepting a loss of boost pressure of the engine (M), to reduce the combustion compression ratio and thus allow a greater quantity of gas to be injected while remaining below the knock limit.

[0029] Indeed, the diesel internal combustion engine has a higher combustion compression ratio than a gasoline internal combustion engine, and the injection of a gas can trigger destructive knocking before the initialization of combustion is made by the direct injection of diesel into the combustion chamber of the cylinder.

[0030] Advantageously, according to one embodiment, the reduction of the turbo boost pressure (T) compared to the original configuration is achieved by a physical adjustment of the turbo boost pressure which is carried out at the level of the wastegate.

[0031] Advantageously, according to one embodiment, the reduction of the turbo boost pressure (T) compared to the original configuration is achieved by downloading an engine control software version onto a retained engine control computer (Cl) by programming a lower turbo boost pressure.

[0032] Advantageously, according to one embodiment, the original electronic injection control unit (Cl) uses the measurement of the turbo boost pressure by a pressure sensor and the reduction of the turbo boost pressure (T) compared to the original configuration is achieved by tricking the original electronic injection control unit (Cl) by replacing the original pressure sensor with a pressure sensor giving a turbo boost pressure measurement higher than the pressure actually measured.

[0033] Advantageously, according to one embodiment, the original electronic injection control unit (Cl) uses the turbo boost pressure measurement from a pressure sensor, and the reduction of the turbo boost pressure (T) compared to the original configuration is achieved by the electronic gas injection control unit by tricking the original electronic injection control unit (Cl) by intercepting the original pressure measurement signal and modulating it to give a turbo boost pressure measurement signal. responding to a pressure higher than the pressure actually measured.

[0034] Advantageously in terms of power, the decrease in boost pressure is compensated to within 10% by the additional power provided by the injection of gas in addition to the injection of diesel fuel.

[0035] The gas can be either natural gas in gaseous form or LPG (Liquefied Petroleum Gas).

[0036] Advantageously, the gas is methane rather than butane, propane or a mixture of the two such as LPG (Liquefied Petroleum Gas).

[0037] Indeed, methane, composed of a single carbon atom, is a fuel that is more difficult to ignite than butane, propane, or a mixture of the two such as LPG (Liquefied Petroleum Gas), which contain several carbon atoms and break down chemically more easily.

[0038] On the one hand, methane, with an octane rating therefore higher than that of LPG, can be injected in greater quantities at the knock limit, and on the other hand, in terms of greenhouse gas emissions, it will emit less CO2 than LPG due to its single carbon atom.

[0039] Advantageously, the conversion process involves adding a knock sensor to the engine and the gas injection system computer (C2) is connected to this knock sensor.

[0040] Indeed, it is possible to calibrate the LPG computer in open loop by adopting a safety margin with regard to the risk of knocking, but it is more advantageous to operate at the knock limit in closed loop operation.

[0041] Advantageously, the conversion process includes adding a temperature sensor on the engine exhaust line and the gas injection system computer (C2) is connected to this temperature sensor.

[0042] Indeed, it is possible to calibrate the LPG computer in open loop by adopting a safety margin with respect to the risk of excessive exhaust temperature, but it is more advantageous to operate at the limit of the risk of excessive exhaust temperature in closed loop operation.

[0043] Advantageously, the conversion process includes adding an oxygen sensor to the engine exhaust line and the gas injection system computer (C2) is connected to this oxygen sensor.

[0044] Indeed, it is possible to calibrate the LPG computer in open loop by adopting a safety margin with regard to the risk of excessive richness of the air, diesel and gas mixture, but it is more advantageous to operate in closed loop from an oxygen sensor installed on the exhaust. Industrial application

[0045] In terms of industrial application, the process relates to the conversion of diesel thermal vehicles already in circulation with an optimization of the percentage of gas compared to the original fuel.

[0046] The present invention is in no way limited to the embodiments described and represented, but a person skilled in the art will be able to make any variation in accordance with their spirit for implementations adapted to each specific context.

Claims

Claims

1. Method for converting vehicles (V) already put into circulation comprising a diesel thermal engine (M) to a dual-fuel gas version with optimization of the gas percentage characterized by the fact that the diesel thermal engine (M) is supercharged by a turbo (T), that the method consists at least in the addition of a second tank (R2) with its feed neck and its filling orifice (02) with gas in addition to the original tank (RI) with its feed neck and its filling orifice (01) with the original fuel, consists at least in the addition of an injection system with its own electronic computer (C2) and its injectors (12) for the gas in addition to the original injection system with the original electronic injection computer (Cl) and its injectors (II) for the original fuel,as well as the removal of turbocharging (T) or the reduction of turbocharging pressure (T) compared to the original configuration.,

2. Method according to claim 1 characterized in that the reduction of the boost pressure by the turbo (T) compared to the original configuration is carried out by a physical adjustment of the turbo boost pressure which is carried out at the level of the wastegate.

3. Method according to claim 1 characterized in that the reduction of the turbo boost pressure (T) compared to the original configuration is carried out by downloading an engine control software version onto an engine control computer (Cl) retained by programming a lower turbo boost pressure.

4. Method according to claim 1 characterized in that the original electronic injection computer (Cl) uses the measurement of the turbo boost pressure by a pressure sensor and that the reduction of the turbo boost pressure by the turbo (T) compared to the original configuration is carried out by deceiving the original electronic injection computer (Cl) by replacing the original pressure sensor with a pressure sensor giving a turbo boost pressure measurement higher than the pressure actually measured.

5. Method according to claim 1 characterized in that the calculator original electronic injection (Cl) uses the measurement of the turbo boost pressure by a pressure sensor and that the reduction of the turbo boost pressure (T) compared to the original configuration is carried out by the electronic gas injection computer by deceiving the original electronic injection computer (Cl) by intercepting the original pressure measurement signal and modulating it to give a turbo boost pressure measurement signal corresponding to a higher pressure than the pressure actually measured.

6. Method according to any one of claims 1 to 5, characterized in that in terms of power, the reduction in supercharging pressure is compensated to within 10% by the additional power input linked to the injection of gas in addition to the injection of diesel.

7. A method according to any one of claims 1 to 6 characterized in that the gas is methane rather than butane, propane or a mixture of the two such as LPG (Liquefied Petroleum Gas).

8. Method according to any one of claims 1 to 7, characterized in that the conversion method comprises the addition of a knock sensor to the engine and that the computer of the gas injection system (C2) is connected to this knock sensor.

9. Method according to any one of claims 1 to 8, characterized in that the conversion method comprises the addition of a temperature sensor on the exhaust line of the engine and that the computer of the gas injection system (C2) is connected to this temperature sensor.

10. Method according to any one of claims 1 to 9, characterized in that the conversion method comprises the addition of an oxygen sensor to the engine exhaust line and that the computer of the gas injection system (C2) is connected to this oxygen sensor.

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