Prechamber Device Thermal Stress Reduction via Composite Core

Solution Overview

Problem

Indirect injection internal combustion engines face significant thermal stress issues in prechamber devices due to their proximity to the ignition source, leading to premature wear and costly maintenance.

Innovation Solution

A prechamber device design featuring a shell made of high-strength material with a thermally conductive core, where the core is in physical contact with both the interior and exterior portions and exposed through openings, allowing for efficient heat dissipation using coolant passages.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the prechamber device uses a shell made of high-strength material to withstand thermal stress, then the strength is improved, but the thermal conductivity is reduced leading to poor heat dissipation

Engineering Contradiction:

ImprovestrengthVSAvoidheat dissipation

Core Design Contradiction:

StrengthVSTemperature

Solution Approach 1:

The prechamber device employs a composite structure consisting of a shell made of high-strength material and a thermally conductive core material positioned within the shell. The shell provides the necessary mechanical strength to withstand thermal stress, while the thermally conductive core material facilitates efficient heat dissipation from the combustion chamber through its high thermal conductivity, thereby resolving the contradiction between strength and heat dissipation capabilities

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The invention applies different material properties to different regions of the prechamber device: the shell is made of high-strength material to handle mechanical and thermal stress, while the core material is specifically selected for its high thermal conductivity to optimize heat dissipation in the central region. This local differentiation of material qualities allows each region to perform its specific function optimally without compromising the other

Inventive Principle:

Principle #3Local quality

2Temperature

If the prechamber device uses a thermally conductive core material to improve heat dissipation, then the temperature control is improved, but the strength is reduced

Engineering Contradiction:

Improveheat dissipationVSAvoidstrength

Core Design Contradiction:

TemperatureVSStrength

Solution Approach 1:

The prechamber device employs a composite structure consisting of a shell made of high-strength material and a thermally conductive core material positioned within the shell. The shell provides the necessary mechanical strength to withstand thermal stress, while the thermally conductive core material facilitates efficient heat dissipation from the combustion chamber through its high thermal conductivity, thereby resolving the contradiction between strength and heat dissipation capabilities

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The thermally conductive core material acts as an intermediary heat transfer medium between the combustion chamber and the external cooling system. It efficiently conducts heat away from the combustion chamber through its high thermal conductivity, while the outer shell serves as a protective barrier that provides mechanical strength and contains the core material, thus resolving the strength limitation of thermally conductive materials

Inventive Principle:

Principle #24Intermediary (Mediator)

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

The design significantly reduces thermal stresses, extending the prechamber device's lifespan by effectively transferring heat away from high-temperature areas, thereby preventing issues like pre-ignition and tip cracking.

Implementation Method 1

A thermally conductive core portion is positioned within the cavity. The thermally conductive core portion is formed of a second material having a second thermal conductivity higher than the first thermal conductivity

Methodology Applied

Scientific EffectThermal conduction: Conduction (thermal)

Data Source

PatentUS9441528B2Prechamber device for internal combustion engine

Publication Date: 2016.09.13 CUMMINS INTELLECTUAL PROPERTY INC

AI summary

This disclosure relates to an improved prechamber device for an internal combustion engine. The prechamber device is positioned adjacent to a combustion chamber. The improved prechamber device is configured to improve removal of heat from the prechamber device, particularly in the area adjacent to the combustion chamber.