ISSN 0003-701X, Applied Solar Energy, 2018, Vol. 54, No. 2, pp. 99–109. © Allerton Press, Inc., 2018.
Original Russian Text © R.Yu. Akbarov, M.S. Paizullakhanov, 2018, published in Geliotekhnika, 2018, No. 2, pp. 31–41.
Characteristic Features of the Energy Modes of a Large Solar
Furnace with a Capacity of 1000 kW
R. Yu. Akbarov
* and M. S. Paizullakhanov
Materials Science Institute, Research and Production Association Physics–Sun,
Academy of Sciences of the Republic of Uzbekistan, Tashkent, Uzbekistan
Received February 15, 2017
Abstract—The possible energy characteristics of the LSF (large solar furnace with a capacity 1000 kW) based
on numerical calculations are analyzed. The technical characteristics of the LSF are presented. The energy
characteristics of the total system with different inaccuracies of the reflecting surfaces, energy contributions
of certain shelves and groups of heliostats, and the contributions of certain heliostats and shapes of their focal
spot are determined. Empirical formulas are proposed to describe the obtained numerical results. The prob-
lem of implementing the possible energy modes of the LSF with and/or without the inclusion of certain
shelves and groups of heliostats is analyzed. The problem of a change in the energy density distribution in the
focal spot of the LSF during the day is considered.
One of the promising directions in the use of solar
energy is heliomaterials science. As is known, high-
temperature heating by solar radiation has certain
advantages, e.g., the absence of pollution from synthe-
sized materials, instantaneous heating, the possibility
to control the heating and cooling rate, a wide range of
solar radiation, etc. At present, high-temperature solar
technologies are widely applied in many areas of sci-
ence and engineering. In this respect, concentrated
solar energy is an important component among the
available material synthesis methods with a set of
specified properties [1, 2].
The important characteristics of the engineering
processes are the capacity, maximum and average
energy densities, uniformity of the energy density dis-
tribution, focal spot size, character of the energy den-
sity distribution and its change in time, duration of the
process, start and stop mode rate, etc.
A characteristic drawback of solar concentrators, in
particularly, the LSF, is variability of the characteris-
tics of the focal spot with time. This is related, on the
one hand, with the temporary change in the direct
solar radiation value, and on the other hand, with the
condition of the optical and mechanical elements of
the LSF, i.e., the adjustment condition of the mirrors,
angular inaccuracies of the light-reflecting mirrors,
reflection coefficient of the mirrors, condition of the
solar sensors, etc.
Scientists in Uzbekistan have achieved significant
results in high-temperature solar technologies. More
than 150 compositions of various oxide materials hav-
ing unique properties and serving as the basis for func-
tional, structural, and high-refractory ceramics are
developed and synthesized at the LSF, and their ther-
mophysical and other characteristics are studied. The
LSF is a unique instrument for field studies of high-
temperature processes, i.e., on the synthesis and heat
treatment of materials and study of their properties.
The LSF represents a complex optomechanical
aggregate with automatic control systems consisting of
a heliostat field and paraboloid concentrator, which
form a high-density radiation flux in the focal zone of
the concentrator . The furnace is located 50 km
from Tashkent, in the Parkent district. The geograph-
ical location is 41.32° N, 69.74° E; its altitude above
sea level is 1050 m.
The LSF heliostat field is formed by 62 heliostats
located on the smooth slope of a mountain (slope 13°)
in a checkerboard pattern arranged on eight terraces.
All 62 heliostats of the LSF have a similar structure
and dimensions. The reflecting surface of the heliostat
with dimensions of 7.5 × 6.5 m
is f lat, composite, and
consists of 195 facets with dimensions of 0.5 × 0.5 m
and a thickness of 6 mm.
The reflecting surface of the concentrator is a rect-
angular-stepped cutting of a paraboloid of revolution
with a focal distance of 18 m. The height of the mid-
SOLAR POWER PLANTS
AND THEIR APPLICATION