Internal Combustion Engine Trapping Efficiency Determination

Solution Overview

Problem

Existing methods cannot accurately determine the trapping efficiency and scavenging air mass of internal combustion engine cylinders during scavenging, especially at low engine revolutions, leading to inefficient turbocharger operation and torque production.

Innovation Solution

A method that creates an efficiency curve based on injection mass to determine the optimum injection mass, which represents the trapping efficiency and scavenging air mass, using sensors and pressure measurements to calculate the air mass in the cylinder and the difference between inflowing and trapped air masses.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If scavenging is used to reduce turbo lag at low engine revolutions, then torque production is improved, but the ability to accurately determine trapping efficiency and scavenging air mass deteriorates

Engineering Contradiction:

Improvetorque productionVSAvoidtrapping efficiency determination

Core Design Contradiction:

PowerVSMeasurement precision

Solution Approach 1:

The patent introduces an intermediary parameter (injection mass) that can be measured with high precision and uses it as a mediator to indirectly determine the trapping efficiency and scavenging air mass. By creating an efficiency curve that relates injection mass to engine efficiency, the system can accurately derive trapping efficiency without directly measuring the difficult-to-obtain scavenging air mass, thus resolving the measurement precision problem while maintaining the torque improvement benefits of scavenging.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent replaces complex mechanical measurement systems (exhaust gas analysis, high-pressure indicating, offline charging change calculation) with a simpler computational approach based on injection mass measurements and efficiency curve analysis. This substitution maintains measurement accuracy while simplifying the determination process for trapping efficiency during scavenging operations.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Device complexity

If conventional methods are used to determine air mass in the cylinder, then device complexity is reduced, but measurement precision of trapping efficiency deteriorates

Engineering Contradiction:

Improvemeasurement system complexityVSAvoidtrapping efficiency determination

Core Design Contradiction:

Device complexityVSMeasurement precision

Solution Approach 1:

The patent replaces complex mechanical measurement systems (exhaust gas analysis, high-pressure indicating, offline charging change calculation) with a simpler computational approach based on injection mass measurements and efficiency curve analysis. This substitution maintains measurement accuracy while simplifying the determination process for trapping efficiency during scavenging operations.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces an intermediary parameter (injection mass) that can be measured with high precision and uses it as a mediator to indirectly determine the trapping efficiency and scavenging air mass. By creating an efficiency curve that relates injection mass to engine efficiency, the system can accurately derive trapping efficiency without directly measuring the difficult-to-obtain scavenging air mass, thus resolving the measurement precision problem while maintaining the torque improvement benefits of scavenging.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Measurement precision

If exhaust gas analysis is used to determine trapping efficiency, then measurement precision is improved, but device complexity and cost increase

Engineering Contradiction:

Improvetrapping efficiency determinationVSAvoidmeasurement system complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent replaces complex mechanical measurement systems (exhaust gas analysis, high-pressure indicating, offline charging change calculation) with a simpler computational approach based on injection mass measurements and efficiency curve analysis. This substitution maintains measurement accuracy while simplifying the determination process for trapping efficiency during scavenging operations.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent uses inexpensive and readily available injection mass measurement data instead of expensive exhaust gas analysis equipment. By leveraging the existing injection mass measurements and creating an efficiency curve, the system achieves accurate trapping efficiency determination without requiring costly specialized measurement devices, thus reducing device complexity and cost while maintaining measurement precision.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

Data Source

PatentUS8001833B2Method for determining the trapping efficiency and/or a scavenging air mass of an internal combustion engine

Publication Date: 2011.08.23 EI DU PONT DE NEMOURS & CO

AI summary

A method for determining the trapping efficiency and/or a scavenging air mass of an internal combustion engine has the steps of: for operating points (BP), in which a scavenging of a cylinder of the internal combustion engine with air takes places, an efficiency curve (ηKL, ηKL,M1) of the internal combustion engine is created as a function of an injection mass (mK) of fuel in the cylinder, and on the basis of the efficiency curve (ηKL, ηKL,M1) an optimum injection mass (mK,opt) for an optimum efficiency (ηopt,1) of the internal combustion engine is determined, which is a measure for the trapping efficiency and/or a measure for the scavenging air mass of the internal combustion engine.