Resource indexes of flat solar water-heating collectors in hot-water supply systems: 4. Specific collector thermal yield and efficiency

Optimization of geometrical parameters of the heat receiver of a solar air heating collector

“…Substituting ( 4) and ( 6) into formula (7), we obtain the energy of the radiant flux arriving over a period of time τ on the surface of the heat receiver of the installation without chips (8), and with the installation with chips (9):…”

“…[1][2][3]. One of the promising areas of renewable energy is the direct production of environmentally friendly heat for the air conditioning system [4][5][6], drying agricultural products with conversion of solar radiation flux density [7][8][9]. Among the various types of solar thermal systems, solar air heating collector (SAH) is widely used due to its lower cost and simplicity of design [10][11].…”

Theoretical preconditions for the development of mathematical models of the technology of desert plant drying

“…Wet material is a colloidal capillary-porous body; the water in it is bound by various forms of bonds [1]. Water in the micro-pores and capillaries of the body has the least strong bond.…”

Improving automatic control of a solar heating system for increasing its efficiency

“…The variety of types of solar heat supply system (SHS) predetermines the need to develop and apply a large number of options for methods and schemes for their automation [1,2]. When choosing options, the following classification features of systems are taken into account [3]: i) types of heat load -seasonal hot water supply, year-round hot water supply, process load, heat supply; ii) types of systems -autonomous (without a backup source of thermal energy, with a peak fossil fuel boiler, with an electric boiler); centralized (solar installations associated with the heat supply system from the boilerhouse, also from the district boiler house); iii) types of coolant and the number of circulation circuits -water single-circuit systems, liquid doublecircuit and multi-circuit systems; iv) heat carrier circulation methods -thermosyphon (with natural circulation), with forced circulation; v) types of solar collectors -flat solar collectors focusing solar collectors without a tracking mechanism, also with a tracking mechanism, tanks -solar water heaters, jet solar collectors; vi) types of accumulation -daily, seasonal (in accumulator tanks). The properties of the technological process in SHS [4] are characterized by such physical quantities as pressure, level, flow rate and temperature of the coolant.…”