IEEE/CPMT Dinner Meeting:

"Heat Pipes for Electronics Cooling" --
Dr. Boris Yendler (ppt handouts), Lockheed Martin; James Lindemuth (ppt handouts), Thermacore International; Dr. Vivek Mansingh, Applied Thermal Technologies

Wednesday, October 13, 1999
Subsidized buffet dinner ($10 if reserved before Oct. 9; $15 after & at door) served at 6:30, Presentation (no cost) at 7:30.
Location: FAZ restaurant, at the Four Points Hotel, on Mathilda, north of Hiway 237 and Fwy 101 junction, Sunnyvale
PLEASE RSVP (for dinner and/or meeting) by email to Tom Tarter, or call our CPMT hotline at 800-686-9366.

OVERVIEWS:

Dr. Boris Yendler: Advanced Heat Pipes (Loop Heat Pipes) (ppt handouts)

Continuous increases in power consumption of electronic devices such as computers require innovative approaches for thermal management. Use of heat pipes in laptops in particular has increased significantly recently. The next generation of heat pipes, such as loop heat pipes, have significant advantages over conventional heat pipes -- namely, flexibility of transport lines, almost no limit on transport distance, and low sensitivity to gravity.
Basic operational parameters, advantages, and issues of using loop heat pipes in the electronics industry will be discussed.

James E. Lindemuth: Cost Reduction in Loop Heat Pipe Production (ppt handouts)

Utilizing the established manufacturing processes for production of conventional heat pipes, the goal is to also reduce the cost of loop heat pipes. As the performance of processor chips has increased, the use of heat pipes to remove heat from chips has also increased. Increased heat pipe production has required the improvement of heat pipe manufacturing capabilities. As heat pipe manufacturing capabilities have improved, the price of a typical 3mm diameter heat pipe for notebook cooling has decreased. In 1995, the price of a 3mm diameter heat pipe was approximately $25 at a production rate of approximately 700 heat pipes per day. Today, as the manufacturing capabilities approach 20,000 heat pipes per day, the price of a 3mm diameter heat pipe is approximately $1.
Compared to conventional heat pipes, loop heat pipes offer the following additional benefits, including operation several meters against gravity (evaporator above condenser) and vibration isolation. The current price of a typical loop heat pipe for electronics cooling is approximately $1,000, in quantities of 100 heat pipes. As the manufacturing capabilities improve, the cost of a loop heat pipe will decrease. The initial opportunity, whether internally or externally funded, still needs to be identified and pursued to realize this cost reduction.

Dr. Vivek Mansingh: Cooling Portable Electronics with Heat Pipes

With the extraordinary advances in electronics during the last decade, thermal management has become the primary bottleneck to achieving ever-increasing computing power. As computers become ubiquitous, increasing demands are being placed on their robust operation especially in hostile thermal environments. Along with new innovative cooling technologies, an entirely new design methodology needs to be adopted where thermal design challenges are addressed upfront in the product design cycle.
This is especially true for the design of portable electronic products such as laptop computers. Here, the enormity of the problem can be appreciated by examining a few trends. In just the last five years, the total power dissipation of laptops have increased fourfold from 10 to 40W. In the same period, there has been nearly a 50% reduction in the total volume. The thermal design challenge is compounded by the fact that acoustic noise and the temperature of the surface has to be maintained at very low levels.
A thermal design example of a high-end laptop computer will be presented. The design approach reflects an entirely new thermal design methodology incorporating analytical calculations, computational fluid dynamics (CFD) modeling and testing. It starts right after the product concept stage and continues well into the product design cycle. After determining the feasibility, a thorough CFD analysis is performed to find the best locations for air vents, fan and heat sinks. Innovative cooling strategies were used to transport the heat from the CPU to a metal plate under the keyboard using heat pipes. It is an excellent example of use of heat pipe to solve a difficult thermal problem in a commercial product.

Speaker Biographies:

Dr. Boris Yendler has been one of the leaders in research and development of Loop Heat Pipes at Lockheed Martin Corp. Most of his work is devoted to application of new methods for electronics cooling. He has published more than 65 technical papers and made numerous presentations on international and domestic conferences.

Jim Lindemuth is Market Development Manager at Thermacore, Inc. He was in the engineering group at Thermacore's Technology Center from 5/90 to 4/99. He has a BS in Physics from Millersville University (1987) and an M. Eng. in Engineering Science from Penn State (1997). His esearch areas are heat pipes and heat exchangers, and he has 12 publications. He has worked on R&D projects with DOD, DOE, and NASA.

Dr. Vivek Mansingh is the executive Vice President and general manager of Applied Thermal Technologies, Inc. based in Santa Clara, CA. He has previously held positions as director and senior thermal scientist at Fujitsu Computer Packaging Technologies, as Senior Scientist at Hewlett Packard, and as an adjunct professor at Lehigh University. Dr. Mansingh has been one of the leaders in research and development in electronics cooling for the last seventeen years. He has published at least 45 technical papers and received 4 patents in the field of electronics cooling. He also a contributor to the Handbook of Reliability, the International Electronics Packaging Society Conference; the EUROTHERM Conference; the Surface Mount Technology Conference; and the National Electronics Packaging and Production Conference