| 摘要 |
An emitter unit having an elongated flowduct. The flowduct comprises a central elongated control duct of substantially rectangular cross-sectional shape having a width a and two sets of successive like flow pockets located respectively on either side of the control duct and opening into the control duct. Each flow pocket of the sets is defined between a pair of adjacent side walls of a pair of successive baffles of a corresponding set of baffles. Each baffle has baffle side walls which terminate in a baffle edge of width c and of height b, the baffles of one set being respectively directed substantially towards the mid-points of the inter-baffle regions of the opposite set. The baffle edges of each set of baffles are substantially aligned and define one pair of opposite longitudinal sides of the control duct, the other pair of longitudinal sides of the control duct being defined by first and second opposite control duct walls. The aligned edges of one set of baffles are substantially parallel to the aligned edges of the opposite set of baffles. The dimensions of a and c relative to d where d is the minimum throughflow spacing in the flowduct between successive, oppositely directed baffles are such that c lies substantially in the range 0-0.25d and a, lies substantially in the range 0.2d-0.4d. <IMAGE> |
