Single-Phase Data Center Cooling With Counter-Flow Heat Exchangers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Cooling systems for data centers face challenges in efficiently managing the increasing heat loads from high-density computer servers, with existing solutions experiencing pressure drops and compromised performance due to high temperature differences and fluid phase changes.
Innovation Solution
A single-phase fluid cooling system utilizing fluoroketone (FK) fluid with micro-encapsulated phase change material, coupled with multi-row counter-flow heat exchangers and extruded aluminum tubes, which operates under low pressure and is safer and more energy-efficient compared to traditional systems.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If traditional cooling systems use phase change fluids (two-phase flow), then heat transfer efficiency is improved, but pressure drops increase and system reliability deteriorates due to leakage risks and corrosion
Solution Approach 1:
The patent changes the physical state parameter of the cooling fluid from two-phase (phase-changing) to single-phase (liquid-only), using fluoroketone fluid that remains in liquid state throughout the system. This eliminates pressure drops and leakage risks associated with phase change while maintaining effective heat transfer through the single-phase liquid circulation in heat exchangers
Solution Approach 2:
The patent employs fluoroketone fluid, a composite cooling medium that combines the properties of liquid refrigerant with non-corrosive and non-freezing characteristics. This composite material approach allows the system to achieve reliable operation without the harmful effects of traditional phase-change fluids
2Temperature
If cooling systems operate at high temperature differences, then cooling capacity is improved, but pressure drops increase and fluid flow stability deteriorates
Solution Approach 1:
The patent maintains high temperature differences for effective cooling capacity while operating with single-phase liquid fluid that does not undergo phase change. This parameter change from two-phase to single-phase flow eliminates the pressure drops and flow instability that normally occur at high temperature differences in phase-change systems
3Use of energy by moving object
If traditional refrigerant fluids are used, then cooling performance is achieved, but environmental harm increases due to high global warming potential
Solution Approach 1:
The patent substitutes traditional high-GWP refrigerants with fluoroketone fluid that has extremely low global warming potential (GWP < 150). This parameter change in fluid composition maintains adequate cooling performance while dramatically reducing environmental harm and eliminating ozone depletion concerns
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 system achieves higher energy efficiency, reduced leakage risk, and increased 'free cooling' hours with lower fluid flow rates, while maintaining high temperature differences and avoiding corrosion and freezing issues.
Implementation Method 1
pumping a single-phase fluid through the heat exchanger from the second plurality of flat, aluminum-formed tubes to the first plurality of flat, aluminum-formed tubes to transfer heat from the air to the single-phase fluid
Implementation Method 2
The single-phase fluid is a fluoroketone (FK) fluid. In aspects, the FK fluid includes micro-encapsulated, phase change material.
Implementation Method 3
The single-phase fluid is a fluoroketone (FK) fluid. In aspects, the FK fluid includes micro-encapsulated, phase change material.
Implementation Method 4
The fan moves air from the hot aisle through the heat exchanger from the second row to the first row
Data Source
AI summary
A cooling system includes a heat exchanger having one or more rows of multiple flat tubes, louvered fins disposed between pairs of flat tubes, and special header tube connections to form a counter flow heat exchanger. Heat exchangers having multiple rows may be placed near or close to the server racks and may be in fluid communication with an outdoor heat exchanger having one or more rows. A single-phase fluid is pumped through a fluid circuit or loop, which includes the heat exchangers at the server racks and the outdoor heat exchanger. The single-phase fluid circuit including the heat exchangers at the IT racks may alternatively be in thermal communication with a water circuit that includes an outdoor fluid cooler. The flat tubes can be formed tubes with one or more channels, or extruded tubes with multiple channels. The heat exchangers include header tubes/connections, which facilitate easy fabrication and connection between rows and inlet/outlet, and lower the pressure drop.