Electronics Cooling Laboratory
Mechanical and Aerospace Engineering Department


at San Jose State University  
Charles W. Davidson
College of Engineering


The electronics cooling laboratory at SJSU has two primary goals:

        - serving the engineering community by performing applied research for both local and national organizations
fostering students' understanding of the thermal management of electronics.

The joint directors of this lab are Dr. Nicole Okamoto and Dr. Jinny Rhee. Please contact either of them if you would like to discuss sponsorship of a project.

Recent project partners include Hewlett Packard, Cisco Systems, Apple Computer, Therma, Inc., Lockheed Martin, and the National Science Foundation.

                    Experimental Facilities    Computer Modeling Tools     Publications    Recent Projects    Coursework


Numerical simulation of ducted pin fin heat sink © 2006 Melanie Beauchemin

Our current expertise includes


numerical modeling of electronic systems requiring thermal management


experimental testing of electronic components and systems cooled using single-phase convection (both air and liquid)


cooling of high heat density electronics


cooling at high elevations


design and testing of advanced thermal interface materials


micro heat pipes


microchannel heat transfer


modeling of data centers


heat exchanger design and testing

Experimental Facilities

bulletApproximately 1200 square foot laboratory
bulletHigh altitude thermal testing chamber, capable of simulating altitudes of up to 80,000 ft and temperatures from ambient to 160ºC, from Thermal Product Solutions
bulletAMCA 210-99 Airflow Test Chamber from Airflow Measurement Systems; used to measure chassis impedance, generate specified flow rates, and determine fan performance (shown below) 
bulletSmall airflow test chamber for analyzing component-level performance, such as heat sinks.
bulletLow-speed (0-2 m/s), low-turbulence intensity wind tunnel; used for a variety of heat transfer experiments
bulletNational Instruments automated data acquisition system
bulletAgilent automated data acquisition system
bulletInfrared camera
bulletLiquid crystal thermography system
bulletSite license for the data acquisition program LabView
bulletA wide variety of standard laboratory equipment such as handheld thermocouple readers, a high-precision electronic manometer (Microtector), and pressure transducers

Computer Modeling Tools

bulletAcademic site license for the electronics cooling commercial CFD package Flotherm with high-speed computers
bulletAcademic site license for Pro-E, for 3-D solid modelling, and Pro-Mechanica, for finite element analysis
bulletAcademic site license for Engineering Equation Solver (EES), a simultaneous equation solver with thermophysical properties built in that is good for thermal system analysis


AMCA 210-99 Airflow Test Chamber                                Low-Speed Wind Tunnel



            Airflow Test Chamber for Component-Level Testing             High Altitude Chamber


Flow visualization of offset-strip fin array © 1997 Nicole Okamoto

Shown below are recent publications by the lab directors Drs. Rhee and Okamoto (DeJong) with their students and colleagues related to the work of the laboratory.

Journal Publications Related to the Cooling of Electronics

Okamoto, N.C., Hsu, T-R, and Bash, C., 2009, "A Thermal Management of Electronics Course and Laboratory for Undergraduates," Advances in Engineering Education, Vol. 1, No. 3.

Rhee, J., and Bhatt, A., 2007, “Spatial and Temporal Resolution of Conjugate Conduction-Convection Thermal Resistance,” IEEE Transactions on Components and Packaging Technologies, Vol. 30, No. 4, pp. 673-682

Rhee, J., and Hernandez, S.I., 2006, “Thermal Management of Electronics in Telecommunications Products: Designing for the Network Equipment Building System (NEBS) Standards,”  ASME J. Electronics Packaging, Vol. 128, No. 4, pp. 484-493.

Rhee, J., and Moffat, R.J., 2006, "Experimental Estimate of the Continuous One-Dimensional Kernel Function in a Rectangular Duct With Forced Convection, Journal Heat Transfer, Vol. 128, No. 8, pp. 811-818.

DeJong, N.C., and A.M. Jacobi, 2003, “Heat Transfer and Pressure Drop for Flow through Bounded Louvered-Fin Arrays,” Experimental Thermal and Fluid Science, Vol. 27, pp. 237-250.

DeJong, N.C., and A.M. Jacobi, 2003, “Localized Flow and Heat Transfer Interactions in Louvered-Fin Arrays,” International Journal of Heat and Mass Transfer, Vol. 46, pp. 443-455.

Rhee, J., and Azar, K., 1999, “Adjusting Temperature Data for High Altitude” Electronics Cooling Magazine, September, Vol. 5, No. 3. Online version.

DeJong, N.C., and A.M. Jacobi, 1999, “Local Flow Structures and Heat Transfer in Convex-Louver Fin Arrays,” Journal of Heat Transfer, Vol. 121, pp. 136-141.

DeJong, N.C., L.W. Zhang, A.M. Jacobi, S. Balachandar, and D.K. Tafti, 1998, “A Complementary Experimental and Numerical Study of the Flow and Heat Transfer in Offset Strip-Fin Heat Exchangers,” Journal of Heat Transfer, Vol. 120, pp. 690-698.

DeJong, N.C., and A.M. Jacobi, 1997, “An Experimental Study of Flow and Heat Transfer in Parallel-Plate Arrays: Local, Row-by-Row and Surface Average Behavior,” International Journal of Heat and Mass Transfer, Vol. 40, pp.1365-1378.

DeJong, N.C., M.C. Gentry, and A.M. Jacobi, 1997, “An Entropy-Based, Air-Side Heat Exchanger Performance Evaluation Method: Application to a Condenser,” International Journal of HVAC&R Research, Vol. 3(3), pp. 185-195.

Conference Proceedings Related to the Cooling of Electronics

Nagendrappa, N., Okamoto, N.C., and Barez, F., 2010 "Thermal Characterization of Fan-in Package-on-Packages," accepted for Semi-Therm 26, Santa Clara, CA.

Meakins, M., Okamoto, N.C., and Bash, C., 2009, "An Energy and Exergy Analysis of Economizer-Based Data Centers, " Proceedings of the ASME International Energy Sustainability Conference, San Francisco, CA.

Singh, S., and Okamoto, N.C., 2009, "Optimal Micro Heat Pipe Configuration for High Performance Heat Spreaders, " IMAPS Workshop on Thermal Management, Palo Alto, CA.

Kam, P.C., Coppage, A.G., Kam, C.C., Shafian, S., Chun, B., and Rhee, J., 2008, "Lead-free, Fluxless Solder Joints to Synthetic Diamond," Proceedings of the 2008 ASME International Mechanical Engineering Congress and Exposition, Oct. 31-Nov.6, Boston, MA
Scanning electron microscopy of a lead-free, fluxless
solder joint from copper to metallization for synthetic
diamond (Kam, P, et al. © 2008 ASME)  

Rogacs, A., and Rhee, J., 2007, "Performance – Cost Optimization of a Diamond Heat Spreader,” Proceedings of 2007 IEEE CPMT Division, Advanced Packaging Materials Conference, San Jose, CA, Oct. 3-5

Bhave, N., and Okamoto, N.C., 2007, "Modeling Noncoplanarity Effects on Thermal Performance of Computer Chips," Proceedings of the IEEE Advanced Packaging Materials Symposium, San Jose, CA, Oct. 3-5.  

Beauchemin, M., and Rhee, J., 2006, “Investigation of Cylindrical Pin Fin Heat Sinks at High Altitude,” Proceedings of the ASME Congress and Exposition, Chicago, IL, Nov. 5-10.

Seidel, R., and Rhee, J., 2006, “Parametric Analysis of Heat Sink Performance at High Altitudes with Air Impingement Cooling,” Proceedings of the ASME Congress and Exposition, Chicago, IL, Nov. 5-10.

Rhee, J., 2006, "The Role of Temperature Superposition in Thermal Management," Proceedings of the 11th IEEE CPMT Advanced Packaging Materials Conference, Atlanta, GA

Bhatt, A., and Rhee, J., 2006, "Thermal Spreading Resistance for Square and Rectangular Entities," Proceedings of the 11th IEEE CPMT Advanced Packaging Materials Conference, Atlanta, GA

Heresztyn, A.J.H., and DeJong Okamoto, N.C., 2005, "Thermal Design of Microchannel Heat Sinks for Low-Orbit Micro-Satellites," Proceedings of the 3rd International Conference on Microchannels and Minichannels, American Society of Mechanical Engineers, Toronto.

Rhee, J., and Wong, G., 2004,  "Characterization of Airflow Impedance in Two Types of Telecommunications Chassis," Proceedings of the 20th Semi-Therm International Conference, San Jose, CA.. pdf

DeJong Okamoto, N.C., and Hsu, T-R, 2004, "Development of a Laboratory Curriculum Devoted to the Thermal Management of Electronics," Proceedings of the ASEE Annual Conference, Salt Lake City. Invited Presentation. pdf

Rhee, J., Danek, C.J., and Moffat, R.J., 1993 “The Adiabatic Heat Transfer Coefficient on the Faces of a Cube in an Electronics Cooling Situation,” Proceedings of the 1993 International Electronics Packaging Conference, Binghampton, NY

    Recent Projects

Top and side view of board level packaging © 2002 Sergio Hernandez


Thermal characterization of a new generation of PoP Packages


Optimal micro heat pipe configuration on high performance heat spreaders


Conjugate Conduction-Convection Thermal Management of LEDs


Energy and Exergy Analysis of Data Center Economizer Systems


Cooling Optimization of High Density Raised Floor Data Centers.


Eliminating the Raised Floor Configuration in a Data Center by Implementing a Single Cooling Coil.


Thermal Stress Analysis of a Heat Spreader and High Heat Flux Source


Modeling Noncoplanarity Effects on Thermal Performance of Computer Chips


Test Fixture for Heat Sink Performance Evaluation


Experimental Investigation of Thermal Interface Materials


Airflow Impedance and Fan Configuration in PC Cooling (senior design project)


Thermal Control of a Low-Earth Orbit Three-Axis Stabilized Micro-Satellite using Microchannel Heat Sink


Application of Microchannel Heat Transfer Enhancement


Characterization of Airflow Impedance for Two Types of Telecommunications Chassis


Determination of Heat Transfer Coefficient using Liquid Crystal Thermography


Preliminary Investigation of Forced Cooling at High Altitudes


Using CFD to Analyze the Effect of Fluid Properties on Micro-Channel Heat Exchanger Behavior






Cooling of high-heat flux electronics using liquid: Student design project from ME 146

In addition to basic courses in thermodynamics, heat transfer, and fluid dynamics, the Mechanical and Aerospace Engineering Department offers the electives "Thermal Management of Electronics" and "Electronics Packaging"

ME 146 Thermal Management of Electronics

The National Science Foundation has sponsored the development of this elective and associated lab relating to the thermal management of electronics. The website for this course includes handouts for lab experiments as well as Powerpoint lectures, which anyone may use. For additional information about any experiment, please contact Dr. Okamoto. If you teach a course on this topic, we would love to post a link to your course webpage.

Depending on semester, this course is taught either by Nicole Okamoto or else Cullen Bash and Chandrakant Patel of Hewlett Packard.

Class topics include:

Sources of heat generation in electronics Thermal resistance method
Pressure drop calculations Fans and heat sinks
Constriction and spreading resistance Thermal interface materials
Thermal stress analysis Air cooling of electronics
Liquid cooling of electronics Computational fluid dynamics
Jedec Standards Cooling of data centers
Heat Pipes Thermo-electric cooling
Vapor compression systems RoHS (restriction of hazardous substances)
Nano-scale heat transfer Temperature measurement methods

ME 145 Electronics Packaging

This course provides an introduction to the fundamental principles of electronic packaging, materials, thermal management, shock and vibrations, EMI/RFI/ESD, fatique, reliability, and standardized test procedures. Simple design to insure product rules and guidelines are presented.

This course is taught by Fred Barez, chair of the MAE Department.

Contact Information

                    Nicole Okamoto                               Jinny Rhee
                    voice: 408-924-4054                        voice: 408-924-3876
                    fax: 408-924-3995                           fax: 408-924-3995
                    email: Nicole.Okamoto at sjsu.edu    email: jrhee at email.sjsu.edu
                    web: www.engr.sjsu.edu/ndejong      web: www.engr.sjsu.edu/jrhee 

Department of Mechanical & Aerospace Engineering
San José State University
One Washington Square
San José, California 95192-0087

Development of this laboratory has been sponsored by the Department of Mechanical and Aerospace Engineering at San Jose State University and the National Science Foundation (through Grant Number 0311713).Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

This website is maintained by Nicole Okamoto.