Heat exchangers of the aforementioned type are known from the prior art and are generally designated as tubular heat exchangers. They are used for heat exchange between two media of different temperature, wherein one medium is conducted into the tubes, mostly brought together as tubular bundles and forming a U, and the other medium is conducted past the tubes of the heat exchanger in a flow that is transverse or longitudinal thereto. A highly heated fluid for the most part in the form of water vapor, water, or inert gas, is used as a second medium from which the heat is removed that is intended to be transferred to the first medium conducted through the tubes.
Preferably, the housing that holds the tubes of the heat exchanger has a number of partitions, and housing sections are formed as the result of their arrangement. The partitions, moreover, serve to secure the position and for a dimensionally stable arrangement of the heat transfer tubes located in the housing of the heat exchanger.
A disadvantage has become evident, however, in that the second medium, conducted through the individual housing sections for heat exchange, cannot be conducted out of the individual housing sections without leaving residue. When using a gaseous fluid in particular, condensable residues in the form of gas bubbles can form that concentrate from the outside in nonaccessible places in the housing—that is, accumulate. As a result, with continued operation of the heat exchanger, the surface originally made available for heat exchange by the heat exchanger tubes is no longer completely utilized since the accumulated fluid residues surround the individual heat exchanger tubes like an insulator. Also, residues form in particular in the area of the partitions, so that as operating time of the heat exchanger increases, insulation layers can be regularly formed that can lower the efficiency of the heat exchanger—sometimes, considerably. Thus, performance losses of up to 50% have been found in operating heat exchangers.