Математичне моделювання зони трубчастого газового нагрівача в конденсаційному режимі роботи

Abstract

RU: Проанализированы течение и теплообмен для трубчатых газовых нагревателей с учетом явления конденсации водяных паров из газовоздушной смеси, которая движется в трубчатой части нагревателя, при охлаждении газовоздушной смеси. Составлены уравнения математической модели, описывающие процессы движения и теплообмена газовоздушной смеси и конденсата внутри излучающей трубы. Указана возможность использования разработанной математической модели для расчета всех параметров течения и теплообмена обогревателей.

EN: Statement of the problem. Infrared tubular gas heaters are designed for burning gas, moving of the heated products of combustion with air inside the tubular heater and heating of the room where the heater is installed with the help of radiant and convective heat exchange with space of the room. Tubular gas heaters are simultaneously sources of heat supply and heating devices. Using of these heaters provides fuel economy and uniform distribution of comfortable heat. Maximum fuel economy can be achieved through using of the mode of condensation of water vapor from the gas–air mixture in the construction of heater. In mathematical models of tubular gas heaters heater is considered as a hydraulic chain with distributed and adjustable parameters by the terminology of the theory of hydraulic chains. However, these mathematical models do not take into account the condensing mode of the work of heaters. The purpose of the article is to build a mathematical model of hydraulic and thermal modes of the area of infrared tubular heaters for the zone of condensation of water vapor from the gas–air mixture. Flow and heat exchange for the tubular gas heaters with regard to the phenomenon of condensation of water vapors from the gas–air mixture, which moves in the tubular part of the heater under cooling of the gas–air mixture are analyzed. Specific areas of flow and heat exchange, starting from the gas burner until intersection of the outlet of fulfilled gas–air mixture into the environment are highlighted. Equations of mathematical model which describe the processes of motion and heat exchange of gas–air mixture and condensate inside the radiating tube are compiled. The possibility of using the developed mathematical model for calculation of the parameters of the flow and heat exchange of the heaters is indicated.