Cold Start Internal Combustion Engine Propane Injection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Internal combustion engines face challenges in starting at low ambient temperatures due to insufficient heat for fuel vaporization, and existing solutions like fuel and block pre-heaters are cumbersome, require external power, and increase weight and complexity.
Innovation Solution
A portable, non-powered external propane injection system is used to initiate ignition in the combustion chamber, utilizing propane's lower flashpoint to facilitate engine heating, allowing the engine to run on regular fuel once warmed.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If fuel and block pre-heaters are used for cold-start engines, then the engine can start at low temperatures, but the system requires external power sources and increases weight
Solution Approach 1:
The patent introduces an intermediary substance (starting fluid with lower flashpoint) that mediates between the cold engine environment and the main fuel. This starting fluid acts as a bridge, allowing ignition to occur at lower temperatures without requiring heavy pre-heating systems or external power sources.
Solution Approach 2:
The patent changes the chemical parameter (flashpoint) of the fuel introduced into the engine. By using a starting fluid with a significantly lower flashpoint than the main fuel, the system enables ignition at cold temperatures without requiring the engine block or fuel system to be pre-heated to high temperatures.
2Reliability
If built-in electric preheaters are applied to enable cold-start, then the engine can ignite fuel in cold conditions, but the device complexity and bulk increase
Solution Approach 1:
The starting fluid serves as a simple intermediary that requires no complex heating elements, thermostats, or control systems. It is introduced directly into the combustion chamber where it vaporizes and ignites at low temperatures, providing a straightforward solution to cold-start problems.
Solution Approach 2:
The starting fluid is a consumable item that is used temporarily during cold-start conditions. After the engine warms up and can run on main fuel alone, the starting fluid is no longer needed and is discarded, eliminating the need for permanent, complex pre-heating infrastructure.
3Reliability
If external power sources are used for pre-heating, then the engine can start at low ambient temperatures, but the system requires additional power infrastructure
Solution Approach 1:
The starting fluid is self-igniting at low temperatures without requiring external power sources. When introduced into the combustion chamber and exposed to the spark plug or hot surfaces, it automatically vaporizes and ignites, providing the necessary heat to ignite the main fuel without any external power input.
Solution Approach 2:
The patent exploits the difference in flashpoint parameters between starting fluid and main fuel. The starting fluid's low flashpoint allows it to vaporize and ignite at ambient cold temperatures, generating the heat needed to raise the engine temperature to a level where the main fuel can also ignite, eliminating the need for external power sources.
4Reliability
If traditional pre-heating methods are used, then the engine can operate in cold environments, but the start time is prolonged
Solution Approach 1:
The starting fluid performs preliminary heating action directly in the combustion chamber. By introducing this highly volatile fuel first, the system quickly raises the temperature of the combustion chamber and surrounding components, creating favorable conditions for main fuel ignition without requiring prolonged pre-heating of the entire engine block.
Solution Approach 2:
The dramatic difference in flashpoint between starting fluid and main fuel creates a rapid temperature increase in the combustion chamber. The starting fluid ignites immediately at low temperatures, releasing energy that quickly raises the local temperature, allowing the main fuel to ignite shortly thereafter and eliminating prolonged wait times.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method significantly reduces engine start time at cold temperatures without the need for extensive setup or external power, eliminating the weight and bulk of built-in electric preheaters, and ensures efficient combustion.
Implementation Method 1
The flashpoint is the lowest temperature where enough fluid can evaporate to form a combustible concentration of gas. The flashpoint of a typical Jet A aviation grade fuel at 3 bar atmospheric pressure is 114° F. Comparatively, the flashpoint of propane at 3 bar atmospheric pressure is 8.3° F.
Implementation Method 2
The insertion of a lower flashpoint fuel into the combustion chamber and subsequent initiation of the ignition process facilitates the propagation of heat throughout the engine even at very low ambient temperatures. Propane, or a similarly low flashpoint fuel source, is injected into the port below the throttle body which flows into the injection chamber and then into the combustion chamber through the transfer and boost ports. The air/fuel mixture in the combustion chamber is ignited using the spark plug and the combustion cycle begins.
Data Source
AI summary
An internal combustion engine has both a primary fuel system and a starting fuel intake assembly. The primary fuel system and the starting fuel intake assembly provide separate flow paths to a common chamber of the internal combustion engine. An external starting fuel source is fluidly connectable with the starting fuel intake assembly of the internal combustion engine, for instance when exposed to a low ambient temperature environment. The internal combustion engine is started while a starting fuel is flowing into a combustion chamber for the internal combustion engine. A primary fuel may also be flowing into the combustion chamber at this time. After the primary fuel is being consistently ignited in the combustion chamber, the flow of starting fuel to the combustion chamber may be terminated and the external starting fuel source may be fluidly disconnected from the starting fuel intake assembly of the internal combustion engine.