Octane separation system and operating method

Patent metadata

Field	Value
Publication number	US-9546583-B2
Application number	US-201514792306-A
Country	US
Kind code	B2
Filing date	Jul 6, 2015
Priority date	Aug 22, 2013
Publication date	Jan 17, 2017
Grant date	Jan 17, 2017

Abstract

An engine method, comprising delivering high octane fuel to a high octane fuel tank and delivering low octane fuel to a low octane fuel tank and injecting atmospheric air into an exhaust system for secondary air injection in response to delivering low octane fuel to an engine.

First claim

The invention claimed is:

1. An engine method, comprising:
delivering high octane fuel to a high octane fuel tank and delivering low octane fuel to a low octane fuel tank, wherein the high octane fuel has a higher octane rating than the low octane fuel;
injecting high octane fuel into an engine using a first routine or low octane fuel using a second routine in response to a first condition and secondary air injection; and
injecting low octane fuel into the engine using the first routine or high octane fuel using the second routine in response to a second condition and secondary air injection.

2. The engine method of claim 1 , further comprising, during secondary air injection, pumping atmospheric air from an air intake into an exhaust system.

3. The engine method of claim 1 , further comprising combusting an amount of unburnt hydrocarbons within exhaust gas following secondary air injection.

4. The engine method of claim 1 , further comprising determining if high octane fuel is desirable or if low octane fuel is desirable in response to a molecular weight, volatility, vapor pressure, refractance, capacitance, density, octane level, or some combination thereof, of the high octane fuel and the low octane fuel.

5. The engine method of claim 1 , wherein the first routine is implemented under the second condition in response to operating conditions being unsustainable with high octane fuel or an unavailability of high octane fuel; and the second routine is implemented under the second condition in response to operating conditions being unsustainable with low octane fuel or an unavailability of low octane fuel.

6. The engine method of claim 1 , wherein the second routine includes increasing an amount of spark retard or decreasing an AFR in response to the second routine being implemented.

7. The engine method of claim 1 , wherein in the first condition, using the first routine comprises injecting the high octane fuel to the engine if high octane fuel is not being injected into the engine, and using the second routine comprises continuing to inject low octane fuel into the engine; and
wherein in the second condition, using the first routine comprises injecting the low octane fuel to the engine if low octane fuel is not being injected into the engine, and using the second routine comprises continuing to inject high octane fuel into the engine.

Assignees

• Ford Global Tech Llc

Inventors

• Leone Thomas G

Classifications

• F02M37/0088

  Multiple separate fuel tanks or tanks being at least partially partitioned · CPC title

• F01N2900/08

  said parameters being related to the engine · CPC title

• F02D41/064

  at cold start (F02D41/067 takes precedence) · CPC title

• F02D41/0025

  Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures · CPC title

• F01N3/22

  Control of additional air supply only, e.g. using by-passes or variable air pump drives · CPC title