Education

  • Ph.D., University of Pennsylvania, 1984
  • M.S., State University of New York, Buffalo, 1981
  • B. Tech., Indian Institute of Technology, Kanpur, 1979

Research Areas and Descriptors

Background

Prior to joining the Georgia Tech faculty in 2001 as a Professor, Dr. Joshi held academic positions at the University of Maryland, College Park, and the Naval Postgraduate School, Monterey, California. He also worked in the semiconductor assembly industry on process thermal model development. He was named to the McKenney/Shiver Chair in 2004.

Research

 

Adya Ali (B.S. Florida State University, M.S. Georgia Tech) is performing a visualization experiment to investigate boiling from microfabricated structures for the cooling of microelectronic components.

 

 

 

 

 

Velocity field and temperature rise above a computer room air conditioning
unit exhaust in a raised floor data center facility, operating at a 100 W/ft^2 power density.

 

 

Dr. Joshi's research deals with transport processes associated with emerging technologies in general. Past focus has been on electronic devices, packages and systems. Thermo/fluid challenges arise in these due to strongly localized heating, a wide range of length scales, a multitude of materials and interfaces, and multiple-coupled transport modes. Advances in these areas require an inter-disciplinary approach involving thermal sciences, materials science, semiconductor devices and manufacturing.

Compact Thermal Management Devices: Electronic systems continue to shrink in size with ever increasing functionality. These trends are resulting in heat fluxes at the chip level of over 100 W/cm2 in some applications. With an upper limit of 70-125°C as the maximum allowable chip temperature in many applications, acceptable thermal management is a key enabler for next generation electronic systems. A number of liquid and air cooling schemes are being investigated. For example, microfabrication techniques are being employed to develop compact two-phase thermosyphons, single phase heat exchangers and thin heat spreaders. A complementary activity is the modeling of these micro-thermal systems.

Conjugate Transport Mechanisms in Multi-Scale Systems: Rapidly shrinking product development times are demanding high fidelity computational tools for thermal design of electronic systems. Dr. Joshi and students have developed experimentally validated modeling methodologies to analyze multi-mode transport in discretely heated systems with multiple length scales.

Energy Efficient Thermal Management of Facilities: Data center facilities face significant thermal challenges due to increasing cabinet heat loads. Energy efficient thermal management approaches and rapid simulation methodologies for their assessment are under development.

Thermal management continues to be identified by the Semiconductor Industries Association Roadmap as one of the five key challenges during the next decade for achieving the projected performance goals of the industry. Our interests will focus broadly over thermal phenomena associated with electronic systems lifecycle. Development of micro-thermo/fluidic systems as well as data center thermal management will be pursued.

Useful aspects of this research include a combination of experimental and computational approaches to handle problems of contemporary interest, and the development of multidisciplinary expertise encompassing transport phenomena, semiconductor devices, and materials.

Distinctions

  • IEEE Fellow, 2012
  • Indian Institute of Technology, Kanpur, Distinguished Alumnus Award, 2010-2011
  • IBM Faculty Award recognizing program quality and its importance to industry, 2008
  • American Society of Mechanical Engineers
    • Electronics and Photonics Division Outstanding Contributions in Thermal Management Award, 2006
    • Journal of Electronic Packaging Associate Technical Editor, 1996-2001
    • Fellow, 2000
    • Curriculum Innovation Award (with A. Bar-Cohen and S. Bhavnani), 1999
  • Institute of Electrical and Electronics Engineers Semi-Therm Significant Contributor Award, 2009
  • American Association for the Advancement of Science Fellow, 2003
  • Naval Postgraduate School Certificate of Recognition for Outstanding Instructional Performance, 1992

Patents

  • Thermal Management Devices, Systems, and Methods, U. S. Patent 7,532,467, with A, Fedorov and S. Launay, May 12, 2009

Representative Publications

  • Lan Tang and Yogendra Joshi. 2005. A Multi-Grid Based Multi-Scale Thermal Analysis Approach for Combined Mixed Convection, Conduction, and Radiation Due to Discrete Heating. Journal of Heat Transfer 127, 18-26.
  • D. Yoo and Y. Joshi. 2004. Energy Efficient Thermal Management of Electronic Components Using Solid Liquid Phase Change Materials. IEEE Transactions on Device Materials and Reliability 4, 641-649.
  • L. Yuan, Y. Joshi, and W. Nakayama. 2003. Effect of Condenser Location and Imposed Circulation on the Performance of a Compact Two-Phase Thermosyphon. Microscale Thermophysical Engineering 7, 163-179.
  • C. Ramaswamy, et al. 2002. High-Speed Visualization of Boiling from an Enhanced Structure. International Journal of Heat Mass Transfer 45, 4761-4771.
  • Y. Joshi, et al. 2000. IC Test Structures for Multilayer Interconnect Stress Determination. IEEE Electron Device Letters 21, 12-14.