Browse Prior Art Database

Module Cooling Using Air Layer Breakers on Covers

IP.com Disclosure Number: IPCOM000099272D
Original Publication Date: 1990-Jan-01
Included in the Prior Art Database: 2005-Mar-14
Document File: 4 page(s) / 88K

Publishing Venue

IBM

Related People

Infantolino, W: AUTHOR [+2]

Abstract

Disclosed is a method of improving module cooling card-on-board packages by adding small projections to the of the card cover above the modules.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 75% of the total text.

Module Cooling Using Air Layer Breakers on Covers

       Disclosed is a method of improving module cooling
card-on-board packages by adding small projections to the of the card
cover above the modules.

      Modules containing integrated circuit chips are soldered print

                            (Image Omitted)

ed circuit cards provide the electrical connections. 
Several of these are connected in a parallel
arrangement on a circuit to form a card-on-board package (Fig. 1).
Cooling air by natural or forced convection enters the parallel
formed by the cards.  The heat generated by the is dissipated by
conduction to the module case and by convection to the passing air
stream.

      As air enters the channel formed by the modules and boundary,
the velocity is reduced next to the solid resulting in a velocity
boundary layer.  This mixing with the bulk of the

                            (Image Omitted)

air stream and reduces convection efficiency. a result of the
exchange of heat between the air and the surfaces, the air next to
the modules becomes hotter the rest of the air stream.  This forms a
thermal layer which impedes the heat transfer from the surface (Fig.
2).

      Small projections on the outer boundary surfaces have shown to
provide a significant increase in module (Fig. 3).  The thermal
resistance between the module air stream has been reduced by as much
as 40% in some positions.  It is...