HVACSYSTEMS DUCTDESIGN SMACNA SHEETMETALANDAIRCONDITIONINGCONTRACTORS' NATIONALASSOCIATION INC. .smacna.org
HVACSYSTEMS DUCTDESIGN FOURTHEDITION-DECEMBER2006 SMACNA SHEETMETALANDAIRCONDITIONINGCONTRACTORS' NATIONALASSOCIATION INC. 4201LafayetteCenterDrive Chantilly VA 20151-1209 .smacna.org
HVACSYSTEMSDUCTDESIGN COPYRIGHT SMACNA 2006 All Rights Reserved by SHEETMETALANDAIRCONDITIONINGCONTRACTORS' NATIONALASSOCIATION INC. 4201 Lafayette Center Drive Chantilly VA 20151-1209 Printed in the U.S.A. FIRST EDITION-JULY1977 SECOND EDITION-JULY 1981 THIRDEDITION-JUNE1990 FOURTH EDITION DECEMBER 2006 Except as allowed in the Notice to Users and in certain licensing contracts no part of this book may be reproduced stored in a retrievable system or transmitted in any form orby any meanselectronic
FOREWORD In keeping with its policy of disseminating information and providing standards of design and construction the Sheet Metal and Air Conditioning Contractors’ National Association Inc. (SMACNA) offers this prehensive funda- mental HVAC Systems-Duct Design manual as part of our continuing effort to upgrade the quality of work produced by the heating ventilating and air conditioning (HVAC) industry. This manual presents the basic methods and proce- dures required to design HVAC air distribution systems. It does not deal with the caleulation of air conditioning loads or room air ventilation quantities. This manual is part one of a three set HVAC Systems Library. The second manual is the SMACNA HVAC Systems-Ap- plications manual that contains information and data needed by designers and installers of more specialized air and hydronic HVAC systems. The third manual is the HVAC Systems-Testing Adjusting and Balncing maual a recently- uplated publication on air and hydronic system testing and balancing. The HVAC duct system designer is faced with many considerations after the load caleulations are pleted and the type of distribution system is determined. This manual provides not only the basic engineering guidelines for the siz- ing of HVAC ductwork systems but also related information in the areas of: a. Materials b. Methods of Construction c. Economics of Duct Systems d. Duct System Layout e. Pressure Losses f. Fan Selection g- Duct Leakage h. Acoustic Considerations i. Duct Heat Transfer j. Testing Adjusting and Balancing With emphasis on energy conservation the designer must balance duet size with the space allocated and duct system pressure loss. Duct pressure loss increases fan power and associated operating costs. Materials equipment and construction methods must be carefully chosen to achieve the most advantageous balance between both initial and life cycle costing considerations. This manual is designed to offer both the HVAC system designer and installer de- tailed information on duct design materials and construction methods. Both U. S. and metric units have been provided in examples calculations and tables. The SMACNA HVAC Systems-Duct Desige manual is intended to be used in conjunction with the American Society of Heating Refrigerating and Air Conditioning Engineers Inc. (ASHRAE) Fuondamentals Handbook. The basic fluid flow equations are not included here but may be found in the ASHRAE handbook. Practical applications of these equations are included through use of reference tables and examples. Some sections of this manual have been reprinted with permission from various ASHRAE publications. Another important source of HVAC systems infommation is the Air Movement and Control Association International Inc. (AMCA). SMACNA and the entire HVAC industry owe these two organizations a debt of gratitude for continued investments testing and development of HVAC standards. Although most HVAC systems are constructed to pressure classifications between minus 3 inches water gage (wg) o 10 inches wg (-750 to 2 500 Pascals Pa) the design methods tables charts and equations provided in this text may be used to design other duct systems operating at higher pressures and temperatures. Air density correction factors for both higher altitudes and temperatures are included. SMACNA recognizes that this manual will be expanded and updated as new material bees available. We will continue to provide the HVAC industry with the latest construction methods and engineering data from recognized sources including SMACNA research programs and the services of local SMACNA Chapters and SMACNA Contrac- tors. SHEET METAL AND AIR CONDITIONING CONTRACTORS' NATIONAL ASSOCIATION INC. HVAC SystemsDuct DesignFourth Edition ii
SMACNADUCTDESIGNCOMMITTEE Ken Groeschel Jr PE Dwight D. Silvia Butters-Fetting Co. Inc. D. D. S. Industries Inc. 1669 South 1st Street Somerset Massachusetts Milwaukee WI 53204 Michael F. Mamayek Eli Howard II Staff Illingworth Corporation SMACNA Inc. Milwaukee Wisconsin Chantilly Virginia Roy Ricei Peyton Collie Staf Licison MeCusker Gill Inc. SMACNA Inc. Hingham Massachusetts Chantilly Virginia TECHNICALCONSULTANT Jeffrey R. Yago P.E. CEM J. R. YAGO & ASSOCIATES Gum Spring Virginia iv HVAC Systems Duct DesignFourth Edition
Ashrae 暖通空调系统管道设计手册.pdf
