RECUPERATOR

A recuperator including neighbouring sheets between which flow passages for air are formed. The sheets are provided with a corrugated profile including peaks, troughs and straight flanks. The peaks and troughs of a sheet are situated at an equal distance from a central plane of the sheet. Neighbouring flanks are directly connected to each other via a peak or trough. Between neighbouring flanks, first and second passage duct parts are formed which are each delimited at one end by a peak or trough and which are open at the end situated opposite the peak. In a direction at right angles to the central plane, the peaks and troughs associated with neighbouring sheets are aligned with respect to each other in such a way that first passage duct parts of a sheet and second passage duct parts associated with a neighbouring sheet are in communication with each other via connecting passage parts which extend between the troughs associated with the one sheet and peaks associated with the other sheet. The first passage duct parts, the second passage duct parts and the connecting passage parts between two sheets together form a flow passage. The smallest distance between the respective peaks and troughs which define the connecting passage parts is greater than 40% of the distance between neighbouring flanks.