Double-pipe eat exchanger

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional double-pipe heat exchangers in vehicle air conditioners face inefficiencies in refrigerant agitation and structural strength, particularly in the agitation of refrigerants flowing between the outer and inner pipes, leading to suboptimal heat exchange efficiency and potential structural weaknesses.

Innovation Solution

A double-pipe heat exchanger design featuring an outer pipe, an inner pipe with a helical member that partitions its internal space, creating two refrigerant flow passages with helical shapes, where refrigerants flow in opposite directions to enhance agitation and structural integrity by aligning helical pitches and abutting lines for improved heat exchange and mechanical strength.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the heat exchanger is designed with a long and thin tubular structure to accommodate the pressure chamber, then the refrigerant flow passages are established, but the structural strength is insufficient

Engineering Contradiction:
Improverefrigerant flow passage configurationVSAvoidstructural strength
Core Design Contradiction:
ProductivityVSStrength

Solution Approach 1:

The invention introduces helical curved grooves on the outer pipe surface and helical fins inside the inner pipe, creating curved flow paths for both refrigerants. These curved structures not only enhance agitation and heat exchange efficiency but also distribute mechanical stresses more evenly along the length of the heat exchanger, improving structural strength despite the long and thin overall configuration.

Inventive Principle:
Principle #14Spheroidality (Curvature)

Solution Approach 2:

The heat exchanger employs a composite structure with an inner pipe and an outer pipe, where the outer pipe features helical grooves that can be filled with reinforcing materials or coated with strengthening layers. This composite approach allows the maintenance of the required long and thin tubular structure for refrigerant flow while enhancing structural strength through material composition and structural reinforcement.

Inventive Principle:
Principle #40Composite materials

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 design effectively agitates both refrigerants, enhancing heat exchange efficiency while improving the structural strength of the heat exchanger by ensuring the refrigerants flow in opposing helical directions and aligning key structural elements, thus addressing the inefficiencies and structural weaknesses of previous designs.

Implementation Method 1

a helical member that is disposed in an internal space of the inner pipe and that helically partitions the internal space... a refrigerant flowing in the second refrigerant flow passage flows into the second refrigerant flow passage from the one side of the inner pipe in the axial direction and then flows out from the other side

Methodology Applied
Scientific EffectHelical flow: Helix

Implementation Method 2

first helical grooves that are formed on an outer surface of the outer pipe... a refrigerant flowing in the first refrigerant flow passage flows into the first refrigerant flow passage from the other side of the inner pipe in an axial direction of the inner pipe and then flows out from one side

Methodology Applied
Scientific EffectHelical flow: Helix

Implementation Method 3

transfers heat between a low-temperature, low-pressure refrigerant flowing to an inner side of the inner pipe and a high-temperature, high-pressure refrigerant flowing between an outer peripheral surface of the inner pipe and an inner peripheral surface of the outer pipe

Methodology Applied
Scientific EffectHeat exchange: Heat Exchanger

Data Source

PatentEP3614074B1Double-pipe eat exchanger
Publication Date: 2022.04.06 VALEO JAPAN CO LTD
  • EP3614074B1 patent drawingFigure 1
  • EP3614074B1 patent drawingFigure 2
  • EP3614074B1 patent drawingFigure 3A~3B

AI summary

A double-pipe heat exchanger is configured with an outer pipe, an inner pipe disposed in an inner portion of the outer pipe, and a helical member that is disposed in an internal space of the inner pipe and that helically partitions the internal space, a gap space between the outer pipe and the inner pipe is a first refrigerant flow passage, the internal space of the inner pipe is a second refrigerant flow passage, a refrigerant flowing in the first refrigerant flow passage flows into the other side of the inner pipe in an axial direction of the inner pipe and then flows out from one side, a refrigerant flowing in the second refrigerant flow passage flows into the one side and then flows out from the other side, and the first refrigerant flow passage is helically partitioned.