dcp & oil immersion cooling

PowerPoint Presentation

Performance Evaluation of Plate-fin and Pin-fin Heat Sinks and Design Optimization of Dynamic Cold Plate (DCP) ByParth Jayeshkumar SoniMS Mechanical Engineering Graduate StudentThe University of Texas at ArlingtonDate:03/21/2016Thesis Advisor: Dr. Dereje AgonaferCommittee Members: Dr. A. Haji-Sheikh Dr. Miguel A AmayaParth Soni Advisor: Dr. Dereje Agonafer1

3/22/2016Parth Soni1

Why Liquid CoolingPower Trends

https://www.cisl.ucar.edu/nar/2006/1.0.sc.jspParth Soni Advisor: Dr. Dereje Agonafer2

23/22/2016Parth Soni

Focus Study 1: Design Validation of Dynamic Cold Plate (DCP)

Study 2: Parametric Study and Performance Comparison of Pin-fin and Plate-fin Heat Sinks for the Application of Oil Immersed Cooling

Parth Soni Advisor: Dr. Dereje Agonafer3


Focus Study 1: Design Validation of Dynamic Cold Plate (DCP)

Study 2: Parametric Study and Performance Comparison of Pin-fin and Plate-fin Heat Sinks for the Application of Oil Immersed Cooling



Original Cold Plate(OCP) vs Dynamic Cold Plate(DCP)One inlet one outletSame water flow for all heat generating componentsParth Soni Advisor: Dr. Dereje Agonafer5

Separate inlet and outlet for different compartment inside cold plateDifferent flow for different compartment


What is DCP?Dynamic cold plate is extended version of original cold plate


CAD modelFin placementReferance heat generating platform

Parth Soni Advisor: Dr. Dereje Agonafer7Dimensions (in mm)ASICs 14.71 13.31 0.8FPGA 10.5 12.7 0.8Reference Platform

Component QuantityPower(W)Base1-ASIC1(B1)40ASIC115FPGA15LICA1370

ASIC:-Application-Specific Integrated CircuitFPGA:-Field-Programmable Gate ArrayMCM serves as basis for design of solution- Power dissipation of 485W over 78mm 78mm


CFD Modeling of DCPParth Soni Advisor: Dr. Dereje Agonafer8

Methodology

Modeling :SolidworksMashing:ICEM CFDAnalysis:Ansys Fluent Parth Soni Advisor: Dr. Dereje Agonafer9

Model of Dynamic Cold Plate

Parth Soni Advisor: Dr. Dereje Agonafer10Dimensions cold lateFoot print : 90*90 mmBase height: 5mm

Fin dimensionsThickness:0.5 mmHeight:2mmLength:29mmPitch:1mm

Dimensions of coverFootprint :90*90 mmHeight: 15mm of inlet outlet:7mm Dimensions from Experimental setup

Purpose of StudyTo visualize the flow in side the cold plateTo validate of the CFD modelFor, Optimization of flow inside cold plateFor, parametric study of DCP


MeshUnstructured meshNo of elements:11,15,321Shape of elements: Tetra elementsMesh algorithm:Robust (octree)top-down meshing approachtop-down meshing approach


Mesh DensityFin surface:0.001 mFin thickness:0.005mOther surfaces:1mParth Soni Advisor: Dr. Dereje Agonafer13

AnalysisModels in fluentEnergy equationTurbulent model: K-epsilon turbulence modelMaterials used in the modeling


K-epsilon Turbulence ModelParth Soni Advisor: Dr. Dereje Agonafer15

Turbulent kinetic energy kEddy Dissipation 10% turbulent intensity from length scale model (Fluent user guide)

Boundary Conditions 4 inlets: Velocity inletsVelocity of water: 4 lpm (Reference experimental data)Temperature: Ambient Pressure : 3000 pa4 outlets: Pressure outletsNo back pressureParth Soni Advisor: Dr. Dereje Agonafer16


ResultsParth Soni Advisor: Dr. Dereje Agonafer17

Particle Tracking


Temperature Distribution

Parth Soni Advisor: Dr. Dereje Agonafer19This figure shows the heat spread on the copper plateAs temperature of B1 increases neighboring chips also shows some higher temperature

Pressure Drop


Pumping power=Pressure drop * Flow ratePumping power= 2.2 W(CFD result)Pumping power=2.76 w(Experimental result)

Validation Between ResultsParth Soni Advisor: Dr. Dereje Agonafer21

Experimental Data: Ruturaj kokates Thesis


ConclusionThus, from the CFD results this model is in good agreement with experimental resultsHence, this model can be used for the further study of optimization and parametric study Parth Soni Advisor: Dr. Dereje Agonafer22

Future WorkStudy 1:This model can be used to optimize the design of the DCPCover design optimization for better flow rateParametric study and documentation of different fins and different cover design Parth Soni Advisor: Dr. Dereje Agonafer23

Focus Study 1:Design Validation of Dynamic Cold Plate (DCP)

Study 2: Parametric study and performance comparison of pin fin and plate fin heat sinks for the application of oil immersed cooling Parth Soni Advisor: Dr. Dereje Agonafer24

Study 1Parametric study and performance comparison of pin fin and plate fin heat sinks for the application of oil immersed cooling for open compute generation one serverParth Soni Advisor: Dr. Dereje Agonafer25

Previous StudyValidation of the model using the identical boundary condition generated in experimentDocumentation of parametric study and the performance of the parallel plate heat sink for the oil immersed applicationOptimization of the parallel plate heat sink design


Parth Soni Advisor: Dr. Dereje Agonafer27Evaluate the performance of pin fin and plate fin heat sink

Compare the thermal resistance of both the heat sinks with current heat sink in use for open compute server

Motivation

MethodologyPlace plate fin and pin fin heat sink in place of the parallel plate heat sink on the validated modelParametric study of heat sinks for same condition as experimental set upBase height Pin thickness and radius Flow rate Documentation of the performance of both heat sinks



Types of Heat Sinks


http://img.diytrade.com/cdimg/720673/6272157/0/1214899819/pin_fin_heat_sink.jpg

http://www.enertron-inc.com/images/resources/forged/forged_2.JPG

http://www.newegg.ca/Product/Product.aspx?Item=N82E16816101827Parallel plate heat sinkPin fin heat sinkPlate fin heat sink

Parth Soni Advisor: Dr. Dereje Agonafer30Material PropertiesPCB, Ram- FR-4 epoxy resinDensity- 1900 kg/m3Thermal conductivity 0.17 W/m KSpecific heat 749 J/kg KHeat sink - AluminumDensity- 2700 kg/m3Thermal conductivity-218 W/m KSpecific heat- 900 J/Kg K

Mineral Oil Properties31STE Oil Company data sheets and MSDS:http://www.steoil.com/msds-tech-dataDensity 1680 Kg/m3Thermal conductivity 0.13 J/kg KSpecific heat 1680 Re: 4.6

Parth Soni Advisor: Dr. Dereje Agonafer

32 Flow ConditionsInlet temperature:30CVolume rate :1 lpmVelocity : 0.00115 m/sPressure : 6 psiRe : 13.6 Parth Soni Advisor: Dr. Dereje Agonafer


CFD Set Up

Parth Soni Advisor: Dr. Dereje Agonafer33Heat sink data:Foot print- 10 cm 7 cmBase height 0.6 cmTotal height 3.1 cmNumber of fins 25Fin radius 0.6 cmModel dataCabinetFootprint: 35*35 cmRamDimension: 14*3*8 cm

Heat sink data:Foot print- 10 cm 7 cmBase height 0.6 cmTotal height 3.1 cmNumber of fins 25Fin thickness 0.4 cm

Why Fixed Flow RatePressure drop in air cooling application is around 4 PaFor parallel plate heat sink in in oil cooling application pressure drop around 0.9 PaWhere as, in oil cooling application pressure drop is around 0.032 Pa

Parth Soni Advisor: Dr. Dereje Agonafer34Pumping power=Pressure drop * Flow rateAdvantage of fix Flow rate conceptLess time consumingEasy to use


ResultsParth Soni Advisor: Dr. Dereje Agonafer35

Grid independent StudyParth Soni Advisor: Dr. Dereje Agonafer36Inlet Temperature - 30 CVolume rate 1 lpm

Flow Rate vs Thermal ResistanceParth Soni Advisor: Dr. Dereje Agonafer37Inlet Temperature - 30 C

Base Height vs Thermal ResistanceParth Soni Advisor: Dr. Dereje Agonafer38Inlet Temperature - 30 CVolume rate 1 lpm

Include pic of base3/22/2016Parth Soni38

Fin Height and Fin Radius vs Thermal Resistance for Pin Fin Heat SinkParth Soni Advisor: Dr. Dereje Agonafer39

Highlight optimize zone3/22/2016Parth Soni39

Fin Height And Fin Thickness vs Thermal Resistance for Plate fin heat sinkParth Soni Advisor: Dr. Dereje Agonafer40

ConclusionBase height: Optimize base height can be 0.6cm as after that the thermal resistance is not varying much.Fin height:Fin height shows the optimum result at 2.5 to 3 cm as after that flow passes through lease resistance pathFin radius or thickness:recommended thickness of the fin can be 0.4mm to 0.6 mm (Plate fin) as after that resistance increases and performance decreasesRecommended radius of the fin can be 0.5 to 0.6 mm as after that flow resistance increases and performance decreases


Future WorkPerformance of the other available heat sinks can be documented for the same model as well as higher generation serversThis same can be studied for the fix pumping power method


Parth Soni Advisor: Dr. Dereje Agonafer43Thank YouQuestions?...

dcp & oil immersion cooling

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