Процеси теплопередачі при формуванні відкладень на робочих поверхнях розбірних пластинчастих теплообмінних апаратів

Abstract

Thesis for the Degree of Candidate of Technical sciences on a specialist 05.17.08 – Chemical engineering processes and equipment. – National Technical University "Kharkov Polytechnic Institute", Ministry of Education and Science of Ukraine, Kharkov, 2017. The thesis is dedicated to problems of heat transfer intensification and development of optimal design methods of gasketed plate heat exchangers and their systems with taking into consideration the heat surface fouling during operation. The method of optimum design of plate heat exchanger systems and heat exchangers based on the criterion of reduced costs is developed for the first time. The mathematical model that takes into account the appearance of deposits on heat transfer surfaces in the process operation, was used to calculate the optimal design of plate heat exchangers by reduced costs criterion. The new experimental results in fouling of heat transfer surface when heated saline water were obtained. It is shown that availability of turbulence elements on the surface are greatly reduces the intensity of deposits appearance. In working sugar factory during two season’s sugar juice boiling was monitored on 4 in series gasketed plate heat exchangers. The method of reconstruction by replacing shell-and-tube heaters with plate heat exchangers is developed and scientifically grounded. Modernization involves the pinch analysis of energy efficiency of sugar evaporation station with separation branch of sugar juice preheating system, where heaters installed in series. The further developed asymptotic approach to assessing the nature of the occurrence of deposits is presented as a part of the proposed mathematical model. His physical-mathematical model, which was implemented in the design of the system heaters working sugar plant, is presented. Based on the models and methods of optimal design of gasketed plate heat exchangers mathematical software were created to select the type and calculation of heat exchangers surface by criterion of adjusted cost with the deposits counts appearance during operation.