Additively Manufactured Cooling Fins for Gradient Thermal Conductivity

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing cooling systems for heat-dissipating surfaces, such as those in radar and electronic systems, face challenges in managing temperature gradients, leading to unintentional beam steering and calibration difficulties due to complex coolant flow requirements and inefficient heat transfer.

Innovation Solution

The use of additive manufacturing to create a manifold structure with fins that have varying geometries and material properties along the cooling channel, providing a gradient convection coefficient and thermal conductivity, which reduces temperature rise and maintains a linear heat transfer rate across the heat-dissipating surface.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If traditional cooling systems with uniform fins are used, then the structure is simple to manufacture, but the temperature gradient across the heat-dissipating surface is high causing beam steering and calibration issues

Engineering Contradiction:
Improvetemperature gradientVSAvoidfin structure complexity
Core Design Contradiction:
TemperatureVSDevice complexity

Solution Approach 1:

The patent applies local quality by varying the fin characteristics (geometry, material composition, spacing) at different locations along the cooling channel. Specifically, fins near the inlet have different properties than fins near the outlet, creating a gradient that optimizes heat transfer at each location. This resolves the contradiction by achieving uniform temperature distribution (improving temperature control) while using localized variations rather than complete system redesign (managing complexity).

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent implements parameter changes by systematically varying fin parameters including geometry (height, thickness, spacing), material composition (gradients from aluminum to copper), and arrangement density along the cooling channel length. These parameter variations create a gradient heat transfer coefficient that compensates for the natural temperature drop along the channel, achieving uniform cooling across the heat-dissipating surface while using manufacturable gradient structures.

Inventive Principle:
Principle #35Parameter changes

2Temperature

If coolant flow rate is increased to reduce temperature gradient, then heat transfer improves, but the system complexity and calibration difficulty increase

Engineering Contradiction:
Improvetemperature uniformityVSAvoidcalibration ease
Core Design Contradiction:
TemperatureVSEase of operation

Solution Approach 1:

The patent applies self-service by designing a passive gradient fin structure that automatically compensates for temperature variations along the cooling channel without requiring active flow control or calibration. The gradient in fin properties (from inlet to outlet) creates a corresponding gradient in heat transfer coefficients that naturally balances the temperature distribution. This resolves the contradiction by achieving temperature uniformity through self-regulating geometry rather than complex active control systems.

Inventive Principle:
Principle #25Self-service

3Productivity

If additive manufacturing is used to create gradient fin structures, then heat transfer efficiency improves, but manufacturing complexity increases

Engineering Contradiction:
Improveheat transfer rateVSAvoidmanufacturing ease
Core Design Contradiction:
ProductivityVSEase of manufacture

Solution Approach 1:

The patent applies composite materials by creating fins with graded material composition along their length or across different fin positions. Specifically, the fins transition from aluminum-based materials at the inlet to copper-based materials at the outlet, or use intermediate alloy compositions. This gradient material distribution optimizes heat transfer efficiency (improving productivity) while additive manufacturing enables this complex material distribution in a single integrated structure (managing manufacturing complexity compared to traditional assembly methods).

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The patent applies segmentation by dividing the cooling channel into multiple zones with distinct fin characteristics. The channel is segmented into inlet, middle, and outlet sections, each with fins optimized for their specific thermal conditions. This segmentation allows additive manufacturing to create the gradient structure efficiently (improving heat transfer) while maintaining manufacturing feasibility through systematic zonation rather than continuous complex variations.

Inventive Principle:
Principle #1Segmentation

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 approach effectively minimizes temperature gradients and ensures a consistent heat transfer rate, enhancing the performance and calibration of electronic devices by optimizing heat dissipation through a structured and material gradient design.

Implementation Method 1

The plurality of fins include a material transition area in which the plurality of fins gradually transitions from a first material to second material... the plurality of fins are configured to provide a gradient thermal conductivity across the length of the heat-dissipating surface

Methodology Applied
Scientific EffectHeat conduction: Conduction (thermal)

Implementation Method 2

at least one cooling channel that is connected between the inlet fluid passage and the outlet fluid passage and extends along a length of the heat-dissipating surface

Methodology Applied
Scientific EffectConvection: Convection

Data Source

PatentEP3803252B1Additively manufactured structures for gradient thermal conductivity
Publication Date: 2022.09.28 RAYTHEON CO
  • EP3803252B1 patent drawingFigure 1~2
  • EP3803252B1 patent drawingFigure 3~7
  • EP3803252B1 patent drawingFigure 8~11

AI summary

A manifold structure is provided to cool a heat-dissipating surface and includes an inlet fluid passage, an outlet fluid passage, and at least one cooling channel that is connected between the inlet fluid passage and the outlet fluid passage and extends along a length of the heat-dissipating surface. Additively manufactured fins are arranged in the cooling channel. The fins are configured to provide a geometry transition area between fins having a first geometry and fins having a second geometry, and a material transition area between fins formed of a first material and fins formed of a second material. The manifold structure is configured to provide a gradient convection coefficient by way of the geometry transition area and a gradient thermal conductivity by way of the material transition area across the length of the heat-dissipating surface.