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Document ID (ISN)29105
CIS number 78-706
ISSN - Serial title 0003-4878 - Annals of Occupational Hygiene
Year 1977
Convention or series no.
Author(s) Fletcher B.
Title Centreline velocity characteristics of rectangular unflanged hoods and slots under suction.
Bibliographic information Oct. 1977, Vol.20, No.2, p.141-146. 5 ref.
Abstract Measurement of centreline velocities of these hoods (area 25-900cm2; aspect ratio - the ratio of slot length to its width - 1:1 to 16:1) showed that for a given face area and volume flow the velocity at a fixed point decreases as the aspect ratio increases. Design formulae used to predict these velocities are not valid over the range of aspect ratios usually claimed for them, and a new non-dimensionalised formula taking account of aspect ratio is proposed. A nomogram for the ranges covered by the experiments is given.
Descriptors (primary) exhaust hoods; ventilation design; local exhaust
Descriptors (secondary) aerodynamics; design of equipment; mathematical analysis
Document type -
Subject(s) Heating, ventilation and climate
Broad subject area(s)
Browse category(ies) Ventilation