Dynamische Simulation von Wärmeübertragern

Simulation of the Dynamic Behaviour of Heat Exchangers . Four models for heat exchangers under transient conditions are presented. Three of them describe a single phase heat exchanger, and the forth one is used for the simulation of a condenser. All models are of intermediate complexity and valid for simulation of both single heat exchangers and chemical processes. They use distributed variables and incorporate the calculation of local heat transfer coefficients so that temperature profiles over the apparatus can be determined in addition to the transient behaviour of the outlet variables.     

Methoden zur Verminderung der Ablagerungsbildung in Wärmeübertragern

Methods for Reducing Deposits in Heat Exchangers. The formation of deposits has long (too long) been considered to be unavoidable and to lie outside the responsibility of the designer. Owing to the enormous operating and investment costs caused by deposit formation and to the development of new processes which are precluded by deposit formation, a number of methods have been developed for reducing or completely preventing the fouling of heat exchangers. The lowest investments are required for chemical fluid processing, which can be retro-fitted to an existing plant. However, for long term operation with large flow volumes or on use of toxic additives this advantage can shift towards mechanical cleaning processes. Consideration of the reduction of fouling already during the design of a heat exchanger means that it becomes feasible to build much smaller (and hence also lighter) heat exchangers.     

Bestimmung charakteristischer Geometrieparameter von Thermoblech‐Wärmeübertragern

Pillow‐plate heat exchangers are a promising alternative to conventional heat exchangers. Their design methods are based on characteristic geometric parameters, for which no established determination procedures are available in the literature. In this work, the complex pillow‐plate geometry is reproduced by accurate deformation simulations. In the following step, approximate equations describing the geometry are derived and validated. Based on this validation, suggestions for the preliminary evaluation of the characteristic geometrical parameters are made.