Flat Heat-Exchange Tube Structure to Prevent Gas Bypass

Solution Overview

Problem

Existing heat exchangers in exhaust gas recirculation systems face issues with hot gas bypassing through larger lateral channels, leading to reduced efficiency, fouling, and pressure drop, which are not effectively addressed by additional pieces at the inlet.

Innovation Solution

A flat tube configuration with fins and deformed portions in the curved wall segments to reduce the hydraulic diameter of lateral channels, ensuring hot gas primarily flows through the fins, enhancing heat transfer and preventing fouling.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the lateral channels are left with their original larger hydraulic diameter, then the gas flow resistance is reduced and flow is easier, but the heat exchange efficiency decreases and fouling increases

Engineering Contradiction:

Improvegas flow through lateral channelsVSAvoidheat exchange efficiency

Core Design Contradiction:

Ease of operationVSProductivity

Solution Approach 1:

The patent applies local quality by creating deformed portions at specific locations within the lateral channels rather than uniformly modifying the entire channel. These localized deformations (reducing the hydraulic diameter in specific zones) increase flow resistance only where needed to prevent bypassing, while maintaining ease of flow through the majority of the channel. This resolves the contradiction by making the channel properties non-uniform: easy to flow through most areas, but restricted in specific zones to force gas through the fins.

Inventive Principle:

Principle #3Local quality

2Productivity

If additional pieces are added at the inlet to block lateral channels, then gas flow is directed through fins, but the device complexity increases

Engineering Contradiction:

Improvegas flow direction controlVSAvoidstructure complexity

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The patent merges the function of flow direction control with the existing tube structure by integrating deformed portions directly into the lateral channels of the tube itself. Instead of adding separate blocking pieces at the inlet, the tube wall is deformed to create flow restriction zones that inherently guide gas through the fins. This eliminates the need for additional components while achieving the same flow control objective, thus resolving the contradiction between productivity and device complexity.

Inventive Principle:

Principle #5Merging (Combining)

3Productivity

If the passage section in lateral channels is reduced, then gas flow is directed through fins, but the hydraulic resistance increases

Engineering Contradiction:

Improvegas flow distributionVSAvoidhydraulic resistance

Core Design Contradiction:

ProductivityVSStress or pressure

Solution Approach 1:

The patent applies local quality by creating deformed portions at specific locations within the lateral channels rather than uniformly modifying the entire channel. These localized deformations (reducing the hydraulic diameter in specific zones) increase flow resistance only where needed to prevent bypassing, while maintaining ease of flow through the majority of the channel. This resolves the contradiction by making the channel properties non-uniform: easy to flow through most areas, but restricted in specific zones to force gas through the fins.

Inventive Principle:

Principle #3Local quality

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 solution increases the hydraulic resistance of lateral channels, directing gas flow through the fins for efficient heat exchange, reducing fouling and improving engine performance.

Implementation Method 1

the hydraulic diameter of the lateral channels is larger than the hydraulic diameter of the internal channels... their resistance to the passage of the hot gas flow is lower

Methodology Applied

Scientific EffectHydraulic resistance:

Implementation Method 2

The hot gas gives off its heat to the fins, which in turn transfer said heat to the flat walls of the tube

Methodology Applied

Scientific EffectHeat convection: Convection

Implementation Method 3

The hot gas gives off its heat to the fins, which in turn transfer said heat to the flat walls of the tube

Methodology Applied

Scientific EffectHeat conduction: Conduction (thermal)

Implementation Method 4

a liquid coolant... removing heat from the gas by means of a liquid coolant

Methodology Applied

Scientific EffectHeat convection: Convection

Data Source

PatentUS20260063370A1Tube for heat exchange

Publication Date: 2026.03.05 BORGWARNER EMISSIONS EYSTEMS SPAIN SLU

AI summary

The present invention relates to a device for heat exchange between a hot gas and a liquid coolant. The tube has a flat configuration, with intermediate channels formed by a set of fins and two lateral channels with a larger hydraulic diameter. The invention is characterized by a specific way of reducing the passage section in order to prevent a by-pass effect in the tube so that gas flow is directed mainly through the set of fins.