# US 11,898,506 B1 · Two stage mixed fuel sensing system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,898,506 B1 - Document ID: US11898506B1 - Status: Granted - Kind: B1 - Application number: 18/323,897 - Filed: 2023-05-25 - Granted: 2024-02-13 - Earliest claimed: 2023-05-25 - Assignees: Caterpillar Inc. - Applicants: Caterpillar Inc. - Inventors: Michael David Gerstner; Daniel Raymond Baldwin; Robert Graumüller - Web page: https://patentgrep.com/patent/US11898506B1 ## CPC - F02D 19/061: {by controlling fuel injectors} - F02D 19/081: {Adjusting the fuel composition or mixing ratio; Transitioning from one fuel to the other} - F02D 19/0621: {Purging of the fuel system} - F02D 19/0634: {Determining a density, viscosity, composition or concentration (F02D19/087 takes precedence)} - F02D 19/0649: {Liquid fuels having different boiling temperatures, volatilities, densities, viscosities, cetane or octane numbers} - F02D 19/0655: {at least one fuel being an alcohol, e.g. ethanol (F02D19/084 takes precedence)} - F02D 19/0665: {Tanks, e.g. multiple tanks} - F02D 19/0673: {Valves; Pressure or flow regulators; Mixers} - F02D 19/0684: {High pressure fuel injection systems; Details on pumps, rails or the arrangement of valves in the fuel supply and return systems} - F02D 19/0689: {for in-cylinder direct injection} - F02D 19/0694: {operating with a plurality of fuels} - F02D 19/085: {Control based on the fuel type or composition} - F02D 19/087: {with determination of densities, viscosities, composition, concentration or mixture ratios of fuels} - F02D 41/0025: {Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures} - F02M 25/0227: {Control aspects; Arrangement of sensors; Diagnostics; Actuators} - F02M 25/0228: {Adding fuel and water emulsion} - F02M 37/0064: {for engines being fed with multiple fuels or fuels having special properties, e.g. bio-fuels; varying the fuel composition (controlling engines working with pluralities of fuels F02D19/06)} - F02D 2200/0611: Fuel type, fuel composition or fuel quality - F02D 2200/0614: Actual fuel mass or fuel injection amount - F02M 37/0047: {Layout or arrangement of systems for feeding fuel (fuel injection apparatus characterised by their conduits and venting means F02M55/00; fuel injection apparatus having a common rail F02M63/0225; arrangement of fuel conduits of low pressure fuel injection apparatus F02M69/462)} - Y02T 10/30: Use of alternative fuels, e.g. biofuels - F02D: CONTROLLING COMBUSTION ENGINES (vehicle fittings, acting on a single sub-unit only, for automatically controlling vehicle speed B60K31/00; conjoint control of vehicle sub-units of different type or different function, road vehicle drive control systems for purposes other than the control of a single sub-unit B60W) - F02M: SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract An internal combustion engine system is described herein. The internal combustion engine system uses one or more fuels that may be hydrophilic. The system uses a water measuring sensor to determine the concentration of water in the hydrophilic fuel. To meet power demands, the system uses the measured water concentration to modify data stored in a fuel map. The fuel map provides a controller the pump speeds and mixing ratio of the fuels for a given power level. The system receives that data and modifies it based on the measured concentration of water. ## Claims ### Claim 1 An internal combustion engine, comprising: a combustion cylinder; an injector fluidly connected to the combustion cylinder, the injector being configured to receive a fuel mixture via a fuel line, the fuel mixture comprising a first fuel and a second fuel; a first fuel pump fluidly connected to a first fuel tank, the first fuel pump being configured to direct the first fuel from the first fuel tank to a mixing valve fluidly connected to the fuel line; a second fuel pump fluidly connected to a second fuel tank, the second fuel pump being configured to direct the second fuel from the second fuel tank to the mixing valve; a first water sensor configured to detect a volume of water in the second fuel stored in the second fuel tank and output a first water volume signal; a second water sensor configured to detect a volume of water in an output of the mixing valve and output a second water volume signal; and a controller configured to: receive a power signal indicating a desired power level of the internal combustion engine; determine, based on the desired power level, a default ratio of the second fuel to the first fuel, a flowrate of the first fuel, and a flowrate of the second fuel; determine a concentration of water in the second fuel stored in the second fuel tank based on the first water volume signal; modify the default ratio, the flowrate of the first fuel, and the flowrate of the second fuel based on the concentration of the water in the second fuel; determine a concentration of water in the output of the mixing valve; and modify the flowrate of the first fuel and the second fuel based on the determination of the concentration of water in the output of the mixing valve. ### Claim 2 (depends on 1) The internal combustion engine of claim 1, wherein the first fuel comprises diesel and the second fuel comprises methanol, ethanol, n-propyl alcohol, isopropyl alcohol, or t-butyl alcohol. ### Claim 3 (depends on 1) The internal combustion engine of claim 1, wherein the controller is further configured to: receive a volumetric flowrate of mixed fuel in the fuel line from a flowrate sensor; and modify a first pump signal, a second pump signal, or a mixing signal based on the volumetric flowrate. ### Claim 4 (depends on 1) The internal combustion engine of claim 1, wherein the controller is further configured to output an injector signal to control an opening and closing of the injector based on the power signal. ### Claim 5 (depends on 1) The internal combustion engine of claim 1, wherein the first water sensor is configured to measure a specific gravity of the second fuel to generate the first water volume signal and the second water sensor is configured to measure a specific gravity of the output of the mixing valve to generate the second water volume signal. ### Claim 6 (depends on 1) The internal combustion engine of claim 1, wherein the first water sensor is configured to measure a conductivity of the second fuel to generate the first water volume signal and the second water sensor is configured to measure a conductivity of the output of the mixing valve to generate the second water volume signal. ### Claim 7 (depends on 1) The internal combustion engine of claim 1, wherein the controller is further configured to: receive a second power signal indicating a shutdown of the internal combustion engine; and in response to receiving the second power signal, transmit a gas control signal to open a gas valve, wherein opening the gas valve allows nitrogen to enter the internal combustion engine to purge the internal combustion engine of the first fuel and the second fuel. ### Claim 8 A controller for controlling an internal combustion engine, the controller comprising: a memory storing computer-executable instructions; and a processor in communication with the memory, the computer-executable instructions causing the processor to perform acts comprising: receiving a power signal indicating a desired power level of the internal combustion engine; accessing a fuel map to calculate a default ratio of a second fuel to a first fuel and a flowrate of the first fuel and the second fuel, wherein the fuel map is a table indicating that for a power level, an amount of the first fuel and an amount of the second fuel for the power level; calculating a concentration of water absorbed by the second fuel stored in a second fuel tank based on a water volume signal received from a water sensor; modifying the default ratio, the flowrate of the first fuel, and the flowrate of the second fuel based on the concentration of the water in the second fuel; outputting a mixing signal to modify a position of a mixing valve based on modifying the default ratio; and outputting a first pump signal to change the flowrate of the first fuel pump and a second pump signal to change the flowrate of the second fuel pump based on modifying the flowrate of the second fuel and the first fuel based on the concentration of the water in the second fuel. ### Claim 9 (depends on 8) The controller of claim 8, wherein the first fuel comprises diesel and the second fuel comprises methanol, ethanol, n-propyl alcohol, isopropyl alcohol, or t-butyl alcohol. ### Claim 10 (depends on 8) The controller of claim 8, further comprising computer-executable instructions causing the processor to perform acts comprising: receiving a volumetric flowrate of mixed fuel in the fuel line from a flowrate sensor; and modifying the first pump signal, the second pump signal, or the mixing signal based on the volumetric flowrate. ### Claim 11 (depends on 8) The controller of claim 8, further comprising computer-executable instructions causing the processor to perform acts comprising outputting an injector signal to control an opening and closing of the injector based on the power signal. ### Claim 12 (depends on 8) The controller of claim 8, wherein water sensor is configured to measure a specific gravity of the second fuel to generate the water volume signal. ### Claim 13 (depends on 8) The controller of claim 8, wherein the water sensor is configured to measure a conductivity of the second fuel to generate the water volume signal. ### Claim 14 (depends on 8) The controller of claim 8, further comprising computer-executable instructions causing the processor to perform acts comprising: receiving a second power signal indicating a shutdown of the internal combustion engine; and in response to receiving the second power signal, transmitting a gas control signal to open a gas valve, wherein opening the gas valve allows nitrogen to enter the internal combustion engine to purge the internal combustion engine of the first fuel and the second fuel. ### Claim 15 A method of operating an internal combustion engine, comprising: receiving a power signal indicating a desired power level of the internal combustion engine; accessing a fuel map to calculate a default ratio of a second fuel to a first fuel and a flowrate of the first fuel and the second fuel, wherein the fuel map is a table indicating that for a power level, an amount of the first fuel and an amount of the second fuel for the power level; calculating a concentration of water absorbed by the second fuel stored in a second fuel tank based on a water volume signal received from a water sensor; modifying the default ratio, the flowrate of the first fuel, and the flowrate of the second fuel based on the concentration of the water in the second fuel; outputting a mixing signal to modify a position of a mixing valve based on modifying the default ratio; and outputting a first pump signal to change the flowrate of the first fuel pump and a second pump signal to change the flowrate of the second fuel pump based on modifying the flowrate of the second fuel and the first fuel based on the concentration of the water in the second fuel. ### Claim 16 (depends on 15) The method of claim 15, wherein the first fuel comprises diesel and the second fuel comprises methanol, ethanol, n-propyl alcohol, isopropyl alcohol, or t-butyl alcohol. ### Claim 17 (depends on 15) The method of claim 15, further comprising: receiving a volumetric flowrate of mixed fuel in a fuel line from a flowrate sensor; and modifying the first pump signal, the second pump signal, or the mixing signal based on the volumetric flowrate. ### Claim 18 (depends on 15) The method of claim 15, further comprising outputting an injector signal to control an opening and closing of the injector based on the power signal. ### Claim 19 (depends on 15) The method of claim 15, further comprising measuring a specific gravity of the second fuel to generate the water volume signal. ### Claim 20 (depends on 15) The method of claim 15, further comprising measuring a conductivity of the second fuel to generate the water volume signal.