THERMAL AND AEROMODELS OF ENERGY EQUIPMENT OF RESIDENTIAL COMPLEXES
DOI:
https://doi.org/10.31650/2786-6696-2024-7-118-127Keywords:
residential complexes, boilers, power, energy efficiency, heat transfer, temperature, heat transfer coefficient, pressure, resistance, modeling, improvement.Abstract
During accidents or destruction of the infrastructure of residential complexes at low temperatures, it is necessary to restore the operation of heat supply systems in a short time. It is convenient to use gas tube boilers for this. But we need new solutions to the problems of increasing the power and energy efficiency of equipment and systems due to the reduction of resistances to the movement of liquids or gases, as well as the intensification of heat transfer. Numerous studies have shown that an increase in the heat transfer coefficient at the gas-metal wall interface by 2-5 times leads to an increase in energy consumption of boiler fans by 10 times or more. The article uses three research methods to improve the performance of boilers. Visual diagnostics of the movement of liquids and gases made it possible to identify signs of self-organization of the flow structure. Hydraulic studies in slot channels, where only the height h varied in the range h = 0.2-2.5 mm, confirmed that the distribution structure of the pulsation components of the dynamic part of the energy affects the increase or decrease in speed at a given initial pressure.
The thermal experiment showed that the flow structure also affects the nature of the change in the heat transfer coefficient. For channel sizes where the pulsation components have positive values, the increase in the heat transfer coefficient is much more intense than for sizes where the pulsations have negative values. That is, visual studies of the flow structure and the correct choice of transverse channel sizes can solve the problem of increasing the flow up to 24% without additional energy costs, as well as eliminate the problem of uncertainty when solving the problem of intensifying heat transfer at the gas-metal wall boundary.
Visual studies of the jet in a flooded space provide information for solving the problem of intensifying heat transfer. The use of turbulators in gas-tube boilers ensured an increase in boiler efficiency from hк.1 = 0.84 to hк.2 = 0.929. At the same time, the energy consumption for fan operation changed slightly. The use of visual diagnostics of the flow structure makes it possible to solve hydraulic and thermal problems when developing or improving energy equipment for housing complexes.
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