Master's work
DEVELOPMENT AND RESEARCH OF ZONAL MODEL OF HEATER WELL WITH ONE
OVERHEAD GAS-RING
Heater wells with one overhead gas-ring (OVG) differ the large unevenness of the
temperature field in working space, conditioned the features of teplovydeleniya
of the diffusive torch developed in length, mutual location of gas-ring, dymootvodyaschego
channel and bars. One of methods of improvement of evenness of the temperature
field in a heater well, there is application of the impulsive heating essence
of which consists of the following: continuous serve in the working chamber of
fuel and air in the period of getting up of temperature and their impulsive
serve in the period of self-control. Switching from the minimum expense of
fuel on maximal is carried out at the overfall of temperatures in workingspace
of stove between hotter and cold points
For determination of temperatures hotter and cold points a zonal model which foresees
dividing of working space of heater well into by volume calculation areas is
developed (the height of lower area equals the height of bar); on a horizontal
line - on the number of bars which are located in one row.
For every area of heater well thermal balance is made. From equalization of thermal
balance on every step at times a gas (mixtures of products of combustion and air)
temperature is determined in every area which is utillized farther as a border
condition for the decision of unstationary task for a bar and heat-resistant laying.
The developed model is maximally close to the actual terms, to created in a heater well:
-a model is zonal;
-a gas temperature and temperature of stove settles accounts in 18 - и areas;
-a model is attended, because allows to determine the temperature of warming environment
-on every step at times;
-a model is taken into account by a difficult heat exchange between a calculation
and by contiguous areas ( nearby overhead and nizhnimi);
-heat exchange between the products of combustion a metal and laying in given and
contiguous areas;
the variable function of burning down of fuel is accepted, which can be corrected
both at a mathematical design and by comparing to the actual temperature on an
operating heater well;
-the task of external and internal heat exchange decides in the nonlinear raising,
that dependence of teplofizicheskikh properties of gases is taken into account,
metal, laying from a temperature, dependence of radiation descriptions of products of combustion on a temperature and gas composition.
Thus, the developed model is component part of the mathematical providing of
adjusting of the impulsive mode of heating, allowing to register the temperature
field of metal, laying and gases, similarly to determine the moment of switching of fuel.
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