Closed-Loop Hybrid Cooling for Leak-Resistant Processor Operation

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Solution Overview

Problem

Existing cooling solutions for electronic devices are inadequate to manage the increased thermal energy generated by high-performance components, necessitating improved thermal management systems.

Innovation Solution

A hybrid cooling system combining air and liquid cooling methods, utilizing a hybrid cooling plate, radiator, and fans to efficiently transfer heat from CPUs and GPUs, with a working fluid and pump system to enhance thermal energy rejection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If a liquid cooling system is used to cool high-performance electronic components, then the cooling capacity and efficiency are improved, but the risk of component damage from leaks increases

Engineering Contradiction:
Improvecooling capacityVSAvoidcomponent damage risk
Core Design Contradiction:
TemperatureVSReliability

Solution Approach 1:

The patent introduces air as an intermediary cooling medium that contacts the electronic components directly, while the liquid cooling system is isolated to specific heat rejection areas. This mediator approach allows the liquid cooling benefits to be realized without the liquid directly contacting vulnerable components, thus maintaining high cooling capacity while reducing leak damage risk.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The cooling system is segmented into distinct air-cooled zones (direct component cooling) and liquid-cooled zones (heat rejection via radiator). This segmentation allows each subsystem to optimize its function while minimizing the downsides - air cooling provides safe direct contact with components, while liquid cooling handles the thermal rejection without exposing components to liquid.

Inventive Principle:
Principle #1Segmentation

2Productivity

If a hybrid cooling system combining air and liquid cooling is implemented, then the thermal management efficiency is improved, but the device complexity increases

Engineering Contradiction:
Improvethermal management efficiencyVSAvoidsystem complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent merges air cooling and liquid cooling subsystems into a unified hybrid cooling architecture where both systems work synergistically. The air cooling handles direct component thermal management while the liquid cooling system manages heat rejection, creating a combined system that achieves superior thermal management efficiency despite the increased complexity of integrating multiple cooling mechanisms.

Inventive Principle:
Principle #5Merging (Combining)

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 hybrid cooling system provides enhanced thermal management, allowing higher wattage operation of CPUs and GPUs by maximizing cooling capacity and efficiency, reducing the risk of component damage from leaks, and maintaining optimal operating temperatures.

Implementation Method 1

The working fluid can be operable to receive heat from the cooling plate and reject heat at the radiator

Methodology Applied
Scientific EffectHeat transfer: Convection

Implementation Method 2

A hybrid cooling plate can be operably coupled with the processor socket... The working fluid can be in fluidic communication with the radiator and the hybrid cooling plate

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 3

the one or more cooling fans can be operable to produce an airflow across the hybrid cooling plate, thereby allowing the hybrid cooling plate transfer thermal energy to the airflow

Methodology Applied
Scientific EffectForced convection: Forced Convection

Data Source

PatentEP3942907B1Closed loop hybrid cooling
Publication Date: 2025.09.10 CISCO TECHNOLOGY INC
  • EP3942907B1 patent drawingFigure 1
  • EP3942907B1 patent drawingFigure 2
  • EP3942907B1 patent drawingFigure 3~4

AI summary

A hybrid cooling server assembly can have a printed circuit board (PCB) with a processor socket disposed thereon and a hybrid cooling plate can be operably coupled with the processor socket. A radiator can having a working fluid received therein and be in fluidic communication with the radiator and the hybrid cooling plate by one or more tubular members. One or more cooling fans can be proximal to the radiator. The working fluid can be operable to receive heat from the cooling plate and reject heat at the radiator and the one or more cooling fans can be operable to produce an airflow across the hybrid cooling plate, thereby allowing the hybrid cooling plate transfer thermal energy to the airflow.