1、 AEROSPACE INFORMATION REPORT Electrical and Electronic Equipment Cooling in Commercial Transports Issued 1956-12 Revised 1992-09 Reaffirmed 2010-01 AIR64 REV.B FOREWORD Commercial transport aircraft have become increasingly dependent on electronics for navigation, guidance, communication, and other
2、 aircraft subsystem control functions. The dissipation of heat from these items of electrical and electronic (E/E) equipment is a problem requiring coordinated effort by both the equipment supplier and the airframe manufacturer. The environment in which equipment is installed, the average and local
3、temperatures within the equipment case, and the method of cooling employed have a distinct bearing on the design and reliability of the equipment. There are two basic methods of cooling the E/E equipment: a. Passive cooling b. Active cooling The passive method relies on free or natural convective co
4、oling to the ambient air surrounding the equipment. The active cooling technique is, in most cases, forced-air convective cooling with the air being either drawn or forced through the equipment case or directed around it. Cold plate cooling using air or some other heat transport fluid is also a suit
5、able design solution for certain active cooling problems. The current practice is to allocate a small area within the pressurized shell of the airplane for installation of most of the avionic equipment. Being in the pressurized area, the equipment is normally subject to pressures which vary between
6、a maximum (ground) pressure equivalent of -1000 ft (-305 m) and a minimum (flight) equivalent of 8000 ft (2438 m) altitude. Under abnormal flight conditions, such as depressurization on a passenger aircraft or during a fire fighting procedure on a freighter aircraft, continuous operation at pressure
7、s equivalent to approximately 15 000 ft (4573 m) or 25 000 ft (7622 m) respectively, may occur. Considering worst case transient conditions, such as explosive SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences
8、. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefrom, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be reaffirmed,
9、revised, or cancelled. SAE invites your written comments and suggestions. Copyright 2010 SAE International All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or
10、 otherwise, without the prior written permission of SAE. TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada) Tel: 724-776-4970 (outside USA) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.org SAE values your input. To provide feedbackon this Technical
11、 Report, please visit http:/www.sae.org/technical/standards/AIR64BCOPYRIGHT SAE International (Society of Automotive Engineers, Inc)COPYRIGHT SAE International (Society of Automotive Engineers, Inc)COPYRIGHT SAE International (Society of Automotive Engineers, Inc)COPYRIGHT SAE International (Society
12、 of Automotive Engineers, Inc)COPYRIGHT SAE International (Society of Automotive Engineers, Inc)COPYRIGHT SAE International (Society of Automotive Engineers, Inc)COPYRIGHT SAE International (Society of Automotive Engineers, Inc)COPYRIGHT SAE International (Society of Automotive Engineers, Inc)COPYRI
13、GHT SAE International (Society of Automotive Engineers, Inc)COPYRIGHT SAE International (Society of Automotive Engineers, Inc)COPYRIGHT SAE International (Society of Automotive Engineers, Inc)COPYRIGHT SAE International (Society of Automotive Engineers, Inc)COPYRIGHT SAE International (Society of Au
14、tomotive Engineers, Inc)COPYRIGHT SAE International (Society of Automotive Engineers, Inc)COPYRIGHT SAE International (Society of Automotive Engineers, Inc)COPYRIGHT SAE International (Society of Automotive Engineers, Inc)COPYRIGHT SAE International (Society of Automotive Engineers, Inc)COPYRIGHT SAE International (Society of Automotive Engineers, Inc)COPYRIGHT SAE International (Society of Automotive Engineers, Inc)COPYRIGHT SAE International (Society of Automotive Engineers, Inc)
