Heat Exchanger Opening Layout for Low-Resistance Electric Heating

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing heating devices face challenges in efficiently heating fluid flows while minimizing flow resistance, as increased surface area for better heat transfer often results in higher resistance, and vice versa.

Innovation Solution

The design features a heat exchanger with a larger surface area of openings further away from the heating elements, combined with heat dissipation ribs that increase in distance and size from the nearest heating element, allowing for efficient fluid flow and heat dissipation by optimizing the distance and size of openings and ribs.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the openings of the heat exchanger make up a larger surface area of the inflow side to reduce flow resistance, then fluid flowability is improved, but heat transfer efficiency deteriorates

Engineering Contradiction:
Improvefluid flowabilityVSAvoidheat transfer efficiency
Core Design Contradiction:
Ease of operationVSTemperature

Solution Approach 1:

The heat exchanger is designed with non-uniform opening distribution: larger openings are positioned at the inflow side to minimize flow resistance, while smaller openings are positioned at the outflow side to maximize heat transfer surface area. This local differentiation of opening sizes allows the system to simultaneously achieve good fluid flowability and effective heat transfer without requiring uniform opening dimensions throughout.

Inventive Principle:
Principle #3Local quality

2Ease of operation

If the openings are made larger to reduce flow resistance, then fluid can flow through more easily, but the heat dissipation capability is reduced

Engineering Contradiction:
Improveflow resistanceVSAvoidheat dissipation capability
Core Design Contradiction:
Ease of operationVSLoss of energy

Solution Approach 1:

Different regions of the heat exchanger are assigned different opening characteristics: the inflow region features larger openings to minimize flow resistance and facilitate easy fluid entry, while the outflow region features smaller openings to increase the effective heat transfer surface area and improve heat dissipation capability. This spatial variation in opening quality resolves the contradiction between flow ease and heat dissipation efficiency.

Inventive Principle:
Principle #3Local quality

3Loss of energy

If heat dissipation ribs are placed closer together to improve heat transfer, then heat dissipation is enhanced, but flow resistance increases

Engineering Contradiction:
Improveheat dissipation efficiencyVSAvoidflow resistance
Core Design Contradiction:
Loss of energyVSEase of operation

Solution Approach 1:

The spacing between heat dissipation ribs is varied across different regions of the heat exchanger. In regions where heat transfer is most critical, ribs are positioned closer together to enhance heat dissipation efficiency. In regions where fluid flow is prioritized, ribs are spaced farther apart to minimize flow resistance. This non-uniform rib spacing strategy allows the system to optimize both heat dissipation and fluid flow performance in different locations simultaneously.

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

This configuration achieves a balance between low flow resistance and effective heat dissipation, enabling efficient heating of fluid flows with reduced energy expenditure and improved heat transfer.

Implementation Method 1

PTC heating elements are arranged between the heat exchangers

Methodology Applied
Scientific EffectPTC heating: Joule Heating

Implementation Method 2

the air flow to be heated flows through the heat exchanger

Methodology Applied
Scientific EffectHeat transfer: Convection

Data Source

PatentEP2199704B1Electric heating device
Publication Date: 2014.08.27 BORGWARNER LUDWIGSBURG GMBH
  • EP2199704B1 patent drawingFigure 1~2
  • EP2199704B1 patent drawingFigure 3~4
  • EP2199704B1 patent drawingFigure 5~6

AI summary

The electrical heating device comprises an electrical heating element (5) and a heat exchanger (1) which has an inflow side for passing a heating fluid. A large surface portion of the inflow side has different sizes of the openings, where the large openings are arranged at a large distance from the heating element. The size of the openings increases with increasing the distance from the heating element.