Engine Exhaust Catalyst Heating via Air Injection and Cylinder Deactivation

Solution Overview

Problem

Existing engine systems face challenges in achieving high compression ratios and reducing back pressure, especially in low speed regions, while also efficiently purifying exhaust gases, particularly in catalyst heating modes where low exhaust gas temperatures hinder catalyst activation.

Innovation Solution

The engine system integrates a mechanical turbocharger and an electric supercharger with a cylinder deactivation (CDA) device, allowing for selective deactivation of combustion chambers, bypassing exhaust gas to reduce back pressure and utilizing an air injection device to quickly increase catalyst temperature for improved purification.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If a mechanical turbocharger is used to increase combustion efficiency, then output is improved, but responsiveness is low and back pressure increases

Engineering Contradiction:

Improveengine outputVSAvoidresponsiveness

Core Design Contradiction:

PowerVSSpeed

Solution Approach 1:

The exhaust system is segmented into multiple paths: one path directs exhaust gas to the turbocharger turbine for power generation, while another path allows exhaust gas to bypass the turbocharger. This segmentation enables selective routing of exhaust flow to optimize both power output and responsiveness depending on operating conditions.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

A bypass valve is introduced to dynamically control the exhaust flow distribution between the turbocharger path and the bypass path. The bypass valve opens or closes based on engine operating conditions, allowing the system to adapt exhaust routing in real-time to balance power output and responsiveness.

Inventive Principle:

Principle #15Dynamics

2Power

If a mechanical turbocharger is used to increase combustion efficiency, then output is improved, but back pressure increases

Engineering Contradiction:

Improveengine outputVSAvoidback pressure

Core Design Contradiction:

PowerVSStress or pressure

Solution Approach 1:

The exhaust system is segmented into multiple paths: one path directs exhaust gas to the turbocharger turbine for power generation, while another path allows exhaust gas to bypass the turbocharger. This segmentation enables selective routing of exhaust flow to optimize both power output and responsiveness depending on operating conditions.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

A bypass valve is introduced to dynamically control the exhaust flow distribution between the turbocharger path and the bypass path. The bypass valve opens or closes based on engine operating conditions, allowing the system to adapt exhaust routing in real-time to balance power output and responsiveness.

Inventive Principle:

Principle #15Dynamics

3Use of energy by moving object

If exhaust gas temperature is low in cool engine state, then fuel consumption is reduced, but catalyst purification ratio decreases

Engineering Contradiction:

Improvefuel consumptionVSAvoidexhaust emission

Core Design Contradiction:

Use of energy by moving objectVSObject-generated harmful factors

Solution Approach 1:

The air injection device is activated in advance during cold engine operation to introduce additional air into the exhaust stream. This preliminary action creates conditions for enhanced oxidation reactions in the catalyst, compensating for the low exhaust temperature and ensuring effective emission purification from the start of engine operation.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

By injecting additional air into the exhaust stream during cold operation, the oxygen concentration is increased to promote oxidation reactions in the catalyst. This accelerates the purification process of harmful exhaust components even when exhaust gas temperature is low, maintaining high purification efficiency during cold start conditions.

Inventive Principle:

Principle #38Strong oxidants (Accelerated oxidation)

4Loss of energy

If cylinder deactivation is used to reduce pumping losses, then fuel efficiency is improved, but exhaust gas temperature for catalyst heating decreases

Engineering Contradiction:

Improvepumping lossVSAvoidexhaust gas temperature

Core Design Contradiction:

Loss of energyVSTemperature

Solution Approach 1:

The air injection device is activated in advance during cold engine operation to introduce additional air into the exhaust stream. This preliminary action creates conditions for enhanced oxidation reactions in the catalyst, compensating for the low exhaust temperature and ensuring effective emission purification from the start of engine operation.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

By injecting additional air into the exhaust stream during cold operation, the oxygen concentration is increased to promote oxidation reactions in the catalyst. This accelerates the purification process of harmful exhaust components even when exhaust gas temperature is low, maintaining high purification efficiency during cold start conditions.

Inventive Principle:

Principle #38Strong oxidants (Accelerated oxidation)

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 configuration enhances fuel efficiency by reducing pumping losses, achieves high compression ratios, and improves exhaust gas purification by rapidly heating the catalyst, thus enhancing emissions control.

Implementation Method 1

rotates a turbine by using pressure of exhaust gas discharged from an engine and thereby increases output of the engine by supplying high-pressure air to a combustion chamber by using rotational force thereof

Methodology Applied

Scientific EffectPressure energy conversion: Turbine

Implementation Method 2

an electric supercharger using a motor to drive a compressor to compress external air

Methodology Applied

Scientific EffectElectric motor conversion: Linear Motor

Implementation Method 3

vehicles are equipped with various types of catalyst devices for removing noxious materials such as NOx, CO, and THC contained in exhaust gases

Methodology Applied

Scientific EffectCatalysis: Catalysis

Implementation Method 4

diesel oxidation catalyst (DOC), a diesel particulate filter (DPF), a nitrogen oxide cleaning unit (LNT, lean NOx trap), a selective catalytic reduction (SCR) unit

Methodology Applied

Scientific EffectOxidation: Oxidation

Data Source

PatentUS10458300B2Engine exhaust catalyst heating system

Publication Date: 2019.10.29 HYUNDAI MOTOR CO LTD

AI summary

An engine system may include an intake line, and a cylinder deactivation (CDA) device selectively deactivating a portion of combustion chambers in the engine. The engine system may further include a first exhaust manifold connected to a first plurality of combustion chambers mounted with the CDA device, a second exhaust manifold connected to a second plurality of combustion chambers without the CDA device, a first exhaust line connected to the first exhaust manifold, a second exhaust line connected to the second exhaust manifold, and a third exhaust line connected with the first and second exhaust lines through an exhaust gas processing device. In addition, a turbocharger including a turbine is mounted at the first exhaust line and rotated by exhaust gas. An air injection device may supply air to the second exhaust manifold or the second exhaust line in a catalyst heating mode of the exhaust gas processing device.