SYSTEM AND METHOD FOR DETERMINING THE REID VAPOR PRESSURE OF FUEL COMBUSTED BY AN ENGINE AND FOR CONTROLLING FUEL DELIVERY TO CYLINDERS OF THE ENGINE BASED ON THE REID VAPOR PRESSURE

• US 20160131055A1
• Filed: 11/12/2014
• Published: 05/12/2016
• Est. Priority Date: 08/29/2014
• Status: Abandoned Application

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: JEFFREY, SCOTT
• Application Number:
  US14/539,308
• Publication Number:
  US 20160131055A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: F02D 2200/0611 Fuel type, fuel composition or fuel quality
• CPC Class Codes: F02D 2200/703 Atmospheric pressure
• CPC Class Codes: F02D 41/0007 for control of turbo-charged or super-charged engines control of the pumps per se F02B37/12
• CPC Class Codes: F02D 41/0042 Controlling the combustible mixture as a function of the canister purging, e.g. control of injected fuel to compensate for deviation of air fuel ratio when purging
• CPC Class Codes: F02D 41/0045 Estimating, calculating or determining the purging rate, amount, flow or concentration
• CPC Class Codes: F02D 41/062 for starting F02D41/061 takes precedence
• CPC Class Codes: F02M 25/0836 Arrangement of valves controlling the admission of fuel vapour to an engine, e.g. valve being disposed between fuel tank or absorption canister and intake manifold

Abstract

A system according to the principles of the present disclosure includes a Reid vapor pressure (RVP) module and a fuel control module. The RVP module determines a Reid vapor pressure of fuel combusted by an engine based on a hydrocarbon concentration measured by a hydrocarbon sensor disposed in a fuel system of the engine. The fuel control module controls at least one of a fuel injector of the engine, a purge valve in an evaporative emissions (EVAP) system of the engine, and a vent valve in the EVAP system of the engine to adjust an amount of fuel delivered to cylinders of the engine based on the Reid vapor pressure.

Claims

1. A system comprising:

a Reid vapor pressure (RVP) module that determines a Reid vapor pressure of fuel combusted by an engine based on a hydrocarbon concentration measured by a hydrocarbon sensor disposed in a fuel system of the engine; and

a fuel control module that controls at least one of a fuel injector of the engine, a purge valve in an evaporative emissions (EVAP) system of the engine, and a vent valve in the EVAP system of the engine to adjust an amount of fuel delivered to cylinders of the engine based on the Reid vapor pressure.

2. The system of claim 1 wherein the RVP module determines the Reid vapor pressure further based on a pressure within a fuel tank in the fuel system, a temperature in the fuel tank, and a mathematical constant.

3. The system of claim 2 wherein the RVP module determines the mathematical constant based on a percentage of oxygenated fuel in the fuel that is combusted by the engine.

4. The system of claim 2 wherein the RVP module:

determines a vapor pressure of hydrocarbon fuel that is combusted by the engine based on the hydrocarbon concentration and the fuel tank pressure; and

determines the Reid vapor pressure based on the hydrocarbon vapor pressure.

5. The system of claim 4 wherein the RVP module determines the hydrocarbon fuel vapor pressure based on a product of the fuel tank pressure and a percentage that corresponds to the hydrocarbon concentration.

6. The system of claim 2 wherein the RVP module determines the Reid vapor pressure when a rate of change in at least one of the fuel tank pressure and the fuel tank temperature is less than a predetermined rate.

7. The system of claim 2 wherein the RVP module determines the Reid vapor pressure when the engine is started after the engine is shutdown for at least a predetermined period.

8. The system of claim 2 wherein the RVP module determines the Reid vapor pressure when the fuel tank is refilled with fuel.

9. The system of claim 1 wherein the fuel control module controls the fuel injector to adjust an amount of liquid fuel delivered to the cylinders of the engine based on the Reid vapor pressure.

10. The system of claim 1 wherein the fuel control module controls at least one of the purge valve and the vent valve to adjust an amount of purge vapor delivered to the cylinders of the engine based on the Reid vapor pressure.

11. A method comprising:

determining a Reid vapor pressure of fuel combusted by an engine based on a hydrocarbon concentration measured by a hydrocarbon sensor disposed in a fuel system of the engine; and

controlling at least one of a fuel injector of the engine, a purge valve in an evaporative emissions (EVAP) system of the engine, and a vent valve in the EVAP system of the engine to adjust an amount of fuel delivered to cylinders of the engine based on the Reid vapor pressure.

12. The method of claim 11 further comprising determining the Reid vapor pressure further based on a pressure within a fuel tank in the fuel system, a temperature in the fuel tank, and a mathematical constant.

13. The method of claim 12 further comprising determining the mathematical constant based on a percentage of oxygenated fuel in the fuel that is combusted by the engine.

14. The method of claim 12 further comprising:

determining a vapor pressure of hydrocarbon fuel that is combusted by the engine based on the hydrocarbon concentration and the fuel tank pressure; and

determining the Reid vapor pressure based on the hydrocarbon vapor pressure.

15. The method of claim 14 further comprising determining the hydrocarbon fuel vapor pressure based on a product of the fuel tank pressure and a percentage that corresponds to the hydrocarbon concentration.

16. The method of claim 12 further comprising determining the Reid vapor pressure when a rate of change in at least one of the fuel tank pressure and the fuel tank temperature is less than a predetermined rate.

17. The method of claim 12 further comprising determining the Reid vapor pressure when the engine is started after the engine is shutdown for at least a predetermined period.

18. The method of claim 12 further comprising determining the Reid vapor pressure when the fuel tank is refilled with fuel.

19. The method of claim 11 further comprising controlling the fuel injector to adjust an amount of liquid fuel delivered to the cylinders of the engine based on the Reid vapor pressure.

20. The method of claim 11 further comprising controlling at least one of the purge valve and the vent valve to adjust an amount of purge vapor delivered to the cylinders of the engine based on the Reid vapor pressure.