GB737217A - Improvements in or relating to heat exchangers - Google Patents

Abstract

737,217. Heating air for combustion. MASCHINENFABRIK AUGSBURG-NURNBERG AKT.-GES. April 30, 1953 [April 30, 1952], No. 11976/53. Class 64 (1). In a heat exchanger comprising a plurality of adjacent chambers through which a fluid to be heated is directed over heating tubes, each chamber is subdivided by partition walls into individual channels, and the individual channels of adjacent chambers are so interconnected that the temperature gradient in each chamber is substantially constant. In the form shown, air is heated by passage through a plurality ot superimposed chambers, e.g. 3, 5, through which extend tubes 1 carrying a heating gas. Adjacent chambers inter-communicate through a channelled duct 4, the arrangement being such that heated air from the lower region of one chamber (e.g. the chamber 3) is passed by way of a channel 13a in the duct 4 into the lower region of the succeeding chamber 5 and air from the upper region of the chamber 3 is passed by way of other channels 12a, 12b in the duct 4 (see Fig. 3) to the upper region of the succeeding chamber, and so on, so that air which has been heated by the hottest gas in one chamber is again heated by the hottest gas in the next chamber and vice versa. Valves 19, 20 enable one set of interconnected channels to be isolated if necessary, for cleaning purposes and may be disposed at the entrance to the lowermost chamber 3 (as shown), or in the channels of the duct 4.