Статична математична модель теплового балансу зерносушарки

Abstract

З метою оптимізації роботи зерносушарок, які працюють в багатофакторному середовищі запропонована математична модель процесу сушіння високовологого насіння баштанних культур. Використання статичної імітаційної математичної моделі теплового балансу дає можливість розрахунковим шляхом обирати режими роботи сушарки при відомих вхідних параметрах системи. In connection with constant growth of prices for energy sources, processing units, where there are thermal processes, require special attention due to the high share of energy consumption in the cost structure of products. In the development of modern technology there are several main and auxiliary directions. One of these areas considers the issues of optimizing the operation of grain dryers operating in multi-factor environment. A compromise solution in this matter may be the minimization of energy consumption while maintaining the level of profitability. Interesting object to study from the point of view of the multifactorial environment is dryer high wet seeds of gourds, the main feature of which is actually a multifactorial environment that incorporates the concept of a microclimate, which takes place in the drying zone of the seed and system of heat supply is an integral component of this environment the simulation of this system under the condition of complexity becomes a factor not only desirable and needed. The proposed static model describes the system work of "drying agent – seeds" by optimizing the drying process due to the mathematical modeling of more complete use of heat and energy savings. Factors which are subject to control and regulation, constitute a system, which includes the coolant temperature and seeds and their moisture content, size of the seed layer, the flow rate of the coolant and seeds. The main factors that influence the system are the environmental factors and input parameters of the coolant and seeds. In the drying process parameters influencing the process require optimal operation of the dryer (control parameters). For example, the drying process can be regulated by changing the temperature of the coolant at the inlet to the dryer, the change of the area of contact of seeds with coolant, coolant supply or the seeds. At the same time on the drying parameters will be affected by uncontrolled parameters, such as initial seed moisture content and open air temperature. You need to find the option that within specified conditions would ensure the achievement of the extremal (minimum) values of the heat losses. On the basis of the operational model and the objective function, the efficiency of the process of drying is measured at a specific energy consumption of the process, the speed of drying of seeds and final moisture content. For study parameters of the dryer it is necessary to have data on changes in temperature, moisture content of the drying agent and seed during the drying process. A mathematical model of the drying process allows to determine the dependence of air temperature and seed at the outlet of the dryer when you change the amount of seed and determine the dependence of the air temperature and seed at the exit of the dryer when you change the coolant flow. If the proposed model will be solved for the temperature at the outlet of the dryer and the final drying temperature, changing the temperature of the air entering the dryer, you can choose the drying mode, focusing on the maximum allowable heating temperature of the seeds. Studies conducted using the static simulation of the mathematical model of the heat balance, show that the change of consumption of the seeds and the coolant affect the temperature of the seed to a much lesser extent than changing the temperature of the coolant at the inlet to the dryer. The use of these models allows by calculation select the modes of operation of the dryer with the known input parameters of the system.