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Increasing energy usage efficiency requires enhanced heat energy recuperation between process streams in the industry and civic sector with waste heat utilization. The condensation of different vapours is the process encountered in many industrial applications. Increasing the heat recuperation in this process is possible with efficient heat transfer equipment, among which a Plate Heat Exchanger (PHE) is at the leading position. A number of research works have been conducted in recent years concerning construction development and heat transfer enhancement in conditions of limited pressure drop to increase PHE performance in condensation processes. The results of studies on heat transfer and pressure drop in the two-phase condensing flow inside channels of PHE with different geometries of corrugations are discussed. In many implementations, the total pressure drop allowable for gaseous streams in heat exchangers is relatively small. The structure of two-phase flow in PHE channels of complex geometry is very different than in tubes and flat wall channels. The relative differences in approaches to enhance PHE performance in condensation processes based on its modelling, optimisation and design are analyzed. The directions and prospects for future developments are formulated, and potential savings for the economy and the environmental footprint is presented. [ABSTRACT FROM AUTHOR]

Pressure drop is an important consideration in Total Site Heat Integration (TSHI). This is due to the typically large distances between the different plants and the flow across plant elevations and equipment, including heat exchangers. Failure to consider pressure drop during utility targeting and heat exchanger network (HEN) synthesis may, at best, lead to optimistic energy targets, and at worst, an inoperable system if the pumps or compressors cannot overcome the actual pressure drop. Most studies have addressed the pressure drop factor in terms of pumping cost, forbidden matches or allowable pressure drop constraints in the optimisation of HEN. This study looks at the implication of pressure drop in the context of a Total Site. The graphical Pinch-based TSHI methodology is extended to consider the pressure drop factor during the minimum energy requirement (MER) targeting stage. The improved methodology provides a more realistic estimation of the MER targets and valuable insights for the implementation of the TSHI design. In the case study, when pressure drop in the steam distribution networks is considered, the heating and cooling duties increase by 14.5% and 4.5%. [ABSTRACT FROM AUTHOR]

To incorporate exchanger dimensions as a design objective in plate and fin heat exchangers, a variable that must be taken into consideration is the geometry of the finned surfaces to be used. In this work, a methodology to find the surface geometry that will produce the required heat transfer coefficient and pressure drop to achieve the design targets was developed. The geometry of secondary surfaces can be specified by the fin density, which represents the number of fins per unit length. All other geometrical features, as well as the thermo-hydraulic performance, can be derived from this parameter. This work showed the way finned surfaces are engineered employing generalised thermo-hydraulic correlations as a part of a design methodology. It also showed that there was a volume space referred to as volume design region (VDR) where heat duty, pressure drop, and dimensions could simultaneously be met. Such a volume design region was problem- and surface-specific; therefore, its limits were determined by the heat duty, the pressure drop, and the type of finned surface chosen in the design. The application of this methodology to a case study showed that a shell and tube heat exchanger of 227.4 m2, with the appropriate fin density using offset strip-fins, could be replaced by a plate and fin exchanger with any combination of height, width, and length in the ranges of 0–0.58 m, 0–0.58 m, and 0–3.59 m. The approach presented in this work indicated that heat exchanger dimensions could be fixed as a design objective, and they could effectively be achieved through surface design. [ABSTRACT FROM AUTHOR]