Розробка наукових основ індукованого тепломасообміну та його використання в процесах та обладнанні харчових виробництв: автореф. дис. на здобуття наук. ступеня д-ра. техн. наук: 05.18.12 – процеси та обладнання харчових, мікробіологічних та фармацевтичних виробництв

Abstract

Робота присвячена розробці наукових основ індукованого тепломасообміну (ІнТМО) та його використання в процесах та обладнанні харчових виробництв. Наукова концепція роботи полягає у такому: теорія – індукування тепломасообміну в термостаті з обтюратором флуктуаціями параметрів газу в обтюраторі сприятиме ефективному розсіянню енергії на випаровування рідини; техніка – термостат з обтюратором, що містить рідину та/або вологе колоїдне капілярно-пористе тіло, являє собою керований тепломасообмінний апарат для харчової промисловості. У роботі сформульовано феноменологічну гіпотезу ефекту ІнТМО. Сформульовані необхідні та достатні умови для спостереження і регулювання ефекту ІнТМО. На основі феноменологічних балансних рівнянь отримано рівняння ефекту ІнТМО. Експериментальними дослідженнями доведено основні положення гіпотези ефекту ІнТМО та виявлено можливості його використання для виконання низки теплових операцій харчової промисловості. Теоретичними дослідженнями виявлено особливості механізму та рушійні сили тепломасообміну під час ІнТМО, які дозволяють керувати цим ефектом. Розроблені концептуальні рішення практичної реалізації апаратів із використанням ІнТМО для виконання таких технологічних операцій харчової промисловості: сушіння; гідротермічна обробка; випарювання, згущення; ректифікація, дистиляція; охолодження, термостатування.

Pak A.O. Development of scientific bases of the induced heat and mass transfer and its application in the processes and equipment of food industry. – Manuscript. Dissertation for the Doctor’s degree of technical science by speciality 05.18.12 – Processes and Equipment of Food, Microbiological and Pharmaceutical Industries. – Kharkiv State University of Food Technology and Trade of the Ministry of Education and Science of Ukraine, Kharkiv, 2017. The work is dedicated to the development of scientific background of the induced heat and mass transfer (hereinafter referred to as InHMT) and its applications in processes and equipment of food industry. Phenomenological hypothesis of InHMT effect is formulated. The necessary and sufficient conditions for observing and regulating the effect of INMO are formulated. The equation of InHMT effect is obtained based on phenomenological balance equations. It is found that mass flow of liquid carried out from the thermostat in a gas state, induces the heat flow dissipated inside the thermostat. Phenomenological hypothesis of InHMT effect was proved experimentally. Analysis of the process of heat and mass transfer in the thermostat by the method of phase space has proved that "environment - internal environment of the thermostat" system is a flowing dynamic system in relation to thermal energy and mass. In such dynamic system, the processes of self-organization are possible. Efficient dissipation of thermal energy due to phase transitions of the first kind. It is noted, that the area under the negative part of phase trajectory on the phase area is proportional to heat content of the internal environment of the thermostat spent on the phase transition of fluid to its gas state. This area is a criterion of energy efficiency of InHMT. The concept of "system water" as a liquid phase, which is in the volume of the food system inside the thermostat during the time not less than the characteristic time of the technological operation, which determines the behaviour of heat and mass transfer and functional and technological properties of this food system, is introduced. Investigation of system water demonstrated that addition of pectin, sugar, elamine, starch, animal protein concentrates into food raw materials results in the decrease of the amount of system water participating in InTMO. The researches of dynamic behaviour of model bodies from starch and gluten by EPR-method showed that system water of the investigated bodies has two forms of bond with solid substances. It is established that for starch bodies there are three structures determined by the molar mass of starch. It is noted that the portion of system water that does not participate in InTMO, determines the requirements for storage conditions of food raw materials and products. The influence of the order parameters (size of the thermostat internal volume; physical properties of the internal environment; the presence of steam-proof barriers, gaps in liquid and solid phases inside the thermostat comparable in size to the dimensions of the thermostat internal volume) and manage parameters (thermostat temperature, external airflow parameters (temperature, velocity, angle of obturator airflow)) on InHMT effect are determined. The ranges of rational values of these parameters are defined. It is proved that InHMT effect is impossible without external activation work. External work is performed by air flow, which moves along the obturator. Kinetic energy of the air flow must not be less than the value of InHMT activation energy. It is proved that the general necessary condition for InHMT realization is the support of the integrity of gas environment inside the thermostat. Investigations of the nature of the influence of InHMT at the thermostat temperature higher than the boiling point of the liquid determined the impossibility of achieving boiling temperature during InHMT by this fluid. It was established that if the mixture of liquids with different boiling temperature is used during InHMT, the liquids pass to the gas state in turn. It is proposed development of R-functions method together with small parameter method and Bubnov–Galerkin projection method for solving the problems of heat and mass transfer. Approximate solutions of the problem of temperature and moisture distribution in colloid capillary-porous body with boundary conditions of the third and first kind were obtained. It is proved that application of the developed models without the formation and development of dissipative structures does not give satisfactory results. Analytical view of the function of dissipative structures power development in colloid capillary-porous body during InHMT is obtained. This function described the features of the InHMT effect. Conceptual solution of practical implementation of the devices applying InHMT effect are proposed for such technological operations in food industry: drying; hydrothermal processing; evaporation, condensation; rectification, distillation; cooling, thermostating. The method and apparatus for continuous hydrothermal processing of cereals using InHMT effect are designed. The final product of the developed method is instant porridge. The technological scheme of hydrothermal processing of cereals is developed. The apparatus for hydrothermal processing of cereals with using InHMT effect is calculated based on heat and mass balance equations taking into account InHMT features. It is proved that the development of economic effect is achieved by reducing the number of used technological operations, performing basic operations operation in one device and by reducing energy consumption per unit of a product by more than 1.3 times.