4 research outputs found
The effect of plate corrugations geometry on performance of plate heat exchangers subjected to fouling
The novel approach of estimating the influence of plate corrugations geometry on plate heat exchanger (PHE) operation in conditions of fouling is proposed. It is based on the presented mathematical model of the PHE with commercially produced plates. To account for fouling on the heat transfer surface, the fouling model of reaction and transport type presented in dimensionless form is employed. The influence of plate corrugations geometry on PHE performance is discussed on results of modelling PHE installed for thin juice heating at evaporation station of the sugar factory. The corrugations inclination angle to the main flow direction is considered as the main influencing parameter. The effect of this parameter on fouling intensity is shown for the cases when the plates with different corrugations angle are used in one PHE. The measures to mitigate fouling in PHE by optimal selection of plate corrugations geometry are discussed
The optimal design of welded plate heat exchanger with intensified heat transfer for ammonia synthesis column
The modification of heat exchanger networks of industrial enterprises targeting energy saving solutions requires proper heat transfer equipment. The estimation of the optimal design parameters for heat exchangers requires reliable mathematical models for the description of the thermo-hydraulic processes inside the channels, and adequate optimisation methods. This work proposes the novel mathematical model and optimisation algorithm for the selection of welded plate heat exchanger (WPHE) operating in ammonia synthesis column. It enables finding the optimal design with the specified shape of the corrugated plates, distribution of flows and number of plates and passes. The developed algorithm is implemented in Mathcad software. The application of the proposed approach is illustrated by example in which the resulted WPHE with the cross flow in one pass and overall symmetric counterflow of streams has shown a reduction of heat transfer area 25 % compared to previously tested in industry WPHE with unsymmetric passes arrangement
Mathematical modelling of the thermal and hydraulic behaviour of plate heat exchanger in the fouling conditions
The mathematical model of Plate Heat Exchanger (PHE) subjected to fouling is proposed. It is represented by the system of ordinary differential equations. The model is accounting for the distribution of process parameters along the PHE channel that allows predicting fouling development in time at different locations along the channel length. The development of the fouling deposit is accounted with the fouling model presented by the equation in dimensionless form. The relative influence of different terms is characterized by empirical coefficients which can be identified with the data of monitoring the PHE thermal and hydraulic performance. The model allows also the prediction of pressure drop variation in PHE with the development of fouling deposition layer and respective reduction in channels cross-section area. The application of the model and its accuracy is demonstrated with two case studies considering the monitoring of PHEs thermal and hydraulic performance in the industry at sugar factory and in District Heating system
Mathematical model of plate heat exchanger for utilisation of waste heat from condensable gaseous streams
The mathematical model of vapour condensation from the mixture with noncondensing gas in Plate Heat Exchanger (PHE) channels is presented. The model accounts for the change of process parameters along the heat transfer surface and local features of heat and mass transfer processes in PHEs channels with plates of different corrugations geometry. It consists of the system of ordinary differential equations with considerably nonlinear right parts. The software for its solution by finite difference method is developed. The validity of the model is confirmed by comparison with the experiment for steam-air mixture condensation in a PHE channel sample