Lienhard, John H.
One of the most prominent industrial applications of heat
transfer science and engineering has been electronics thermal
control. Driven by the relentless increase in spatial density of
microelectronic devices, integrated circuit chip powers have
risen by a factor of 100 over the past twenty years, with a
somewhat smaller increase in heat flux. The traditional
approaches using natural convection and forced-air cooling are
becoming less viable as power levels increase. This paper
provides a high-level overview of the thermal management
problem from the perspective of a practitioner, as well as
speculation on the prospects for electronics thermal engineering
in years to come.
Chu, R.C.; Bar-Cohen, Avi; Edwards, David; Herrlin, Magnus; Price, Donald; Schmidt, Roger; Joshi, Jogenda; Chryser, George M.; Garimella, Suresh; Mok, Larry; Sammakia, Bahgat; Yeh, Lian-Tuu
The unique properties of nanostructures associated with
their low dimensionality give rise to new opportunities for research
on nanoscale heat transfer and energy conversion. Inspired
by Majumdar’s analysis of the novel aspects of heat, mass,
and charge flow across the interface between hard and soft materials,
some perspectives about research frontiers in nanoscale
heat transfer and energy conversion are provided.
The summary from Goodson’s group on their recent work
on heat transfer issues in the microelectronics and data storage
industries illustrate the critical role of heat transfer for some
areas of information technology. In this article, we build on
their work and discuss some directions worthy of further
The electronics industry is encountering thermal challenges
and opportunities with lengthscales comparable to or much less
than one micrometer. Examples include nanoscale phonon
hotspots in transistors and the increasing temperature rise in onchip
interconnects. Millimeter-scale hotspots on
microprocessors, resulting from varying rates of power
consumption, are being addressed using two-phase
microchannel heat sinks. Nanoscale thermal data storage
technology has received much attention recently. This paper
provides an overview of these topics with a focus on related
research at Stanford University.
Forsberg, Charles H.
Concerns about the security of oil supplies and the environmental consequences of burning fossil fuels
have transformed the idea of a hydrogen (H2) economy from science fiction into a political bipartisan
vision of our energy future. The challenge is now one of economics and technology. In one context, we
already have a rapidly growing H2 economy, driven by the need for increased supplies of H2 to convert
more abundant lower-grade crude oils into clean liquid fuels. This development is creating the
infrastructure for a global H2 economy and provides powerful incentives to develop better methods of H2
production. The H2 content of liquid fuels is a...
Rosenfeld, Arthur H.
Hard and soft matter can be distinguished by the energy of chemical bonds in comparison with
kBT. At the interface of hard and soft matter, there exists a region of transition between strong
(covalent/ionic/metallic) bonds in solids and weak (van der Waals/hydrogen/electrostatic)
interactions in liquids and polymers. Transport of energy and mass at such interfaces is yet to be
fully explored, but seems both rich in science and of technological importance. This paper
discusses some fundamental issues as well as some technological implications.
Lienhard, John H.
Almost 450 nuclear power plants are currently operating throughout the world and supplying about
17% of the world’s electricity. These plants perform safely, reliably, and have no free-release of byproducts
to the environment. Given the current rate of growth in electricity demand and the ever
growing concerns for the environment, the US consumer will favor energy sources that can satisfy the
need for electricity and other energy-intensive products (1) on a sustainable basis with minimal
environmental impact, (2) with enhanced reliability and safety and (3) competitive economics. Given
that advances are made to fully apply the potential benefits of nuclear energy systems, the next
generation of nuclear...
Amon, Cristina H.
Increases in microprocessor power dissipation coupled with reductions in feature sizes due to
manufacturing process improvements have resulted in continuously increasing heat fluxes. The ever
increasing chip-level heat flux has necessitated the development of thermal management devices
based on spray and evaporative cooling. This lecture presents a comprehensive review of liquid and
evaporative cooling research applied to thermal management of electronics. It also outlines the
challenges to practical implementation and future research needs.
This presentation also describes the development of EDIFICE: Embedded Droplet Impingement
For Integrated Cooling of Electronics. The EDIFICE project seeks to develop an integrated droplet
impingement cooling device for removing chip heat fluxes over 100...
Chu, Richard C.
Bergles, Arthur E.
Phase-change processes, such as pool and flow boiling, are
generally very effective modes of heat transfer. However, the
demands of modern thermal systems have required the
development of methods to enhance boiling systems. While
heat fluxes above 108W/m2 have been accommodated in
carefully controlled situations, the required fluid and the
convective conditions usually dictate maximum heat fluxes
several orders of magnitude lower. Two major contemporary
areas, enhanced surfaces for pool boiling and enhanced surfaces
and inserts for forced convection boiling/vaporization, are
discussed, as they facilitate the attainment of high heat fluxes.
In addition to these passive techniques, active techniques and
compound techniques are mentioned. The taxonomy of
enhanced heat transfer is covered, and...
Avedisian, C. T.
Dhir, Vijay K.
During the last half of the twentieth century, significant
advances have been made in developing an understanding of
phase change heat transfer (e.g., boiling and condensation).
Further advances in phase change heat transfer will continue to
take place motivated by new technologies such as microelectronics,
thermal management in space, advanced terrestrial
and space power systems and processing of designed materials.
In the past, because of the complexity of the processes, very
often we have “oversimplified”, maybe out of necessity, the
modeling of the processes. The resulting weaknesses in our
models and correlations have continued to haunt us whenever
we have encountered new applications. In order to address the
phenomena from basic principles,...