DSpace Collection:https://opendata.uni-halle.de//handle/1981185920/135882024-03-28T22:05:03Z2024-03-28T22:05:03ZAnalysis of electric and thermal efficiency of crystal silicon small power suppliersTursunov, MuhammadjonSabirov, KhabibulloAxtamov, TohirAbdiyev, UmirbekYuldoshov, BoysoriKhaliyarov, JasurBobomuratov, SardorToshpulatov, Sirojiddinhttps://opendata.uni-halle.de//handle/1981185920/1149662024-01-11T02:08:17Z2023-01-01T00:00:00ZTitle: Analysis of electric and thermal efficiency of crystal silicon small power suppliers
Author(s): Tursunov, Muhammadjon; Sabirov, Khabibullo; Axtamov, Tohir; Abdiyev, Umirbek; Yuldoshov, Boysori; Khaliyarov, Jasur; Bobomuratov, Sardor; Toshpulatov, Sirojiddin
Abstract: The article presents the results of studying the electric and thermal efficiency of mobile photovoltaic and photothermal devices (MPVD and MPTD) based on crystalline silicon with a power of 60W panel, designed for the production of electricity and hot water for the domestic needs of rural residents. Our experiment conducted in natural conditions was carried out in the heliopolygon of the Physical-Technical Institute in July of the summer season. The device was manually adjusted and measurements were carried out in the directed mode. Reflectors are installed on the side of the photovoltaic panel (PV) in order to increase the intensity of sunlight in MPTD. As a cooling system, heat collector (HC) is installed in the back of the PV. The HC of the photothermal panel (PVT) is fundamentally different from the system of HC in other works. During the experiment carried out in natural conditions, the effects of the reflectors installed on the front surface of the photothermal device’s PV and the heat collector attached to the back side were determined. Thermal efficiency was 5.5-6 times higher than electric efficiency for PVT panels. And 90% of the solar energy falling on the surface of the photothermal device is converted into useful energy.2023-01-01T00:00:00ZDevelopment and substantiation of energy-saving methods for controlling the modes of operation of centrifugal pumping units in complicated operating conditionsToshov, JavokhirMakhmudov, AzamatKurbonov, OybekArzikulov, GolibMakhmudova, Gulnozahttps://opendata.uni-halle.de//handle/1981185920/1149652024-01-11T02:08:31Z2023-01-01T00:00:00ZTitle: Development and substantiation of energy-saving methods for controlling the modes of operation of centrifugal pumping units in complicated operating conditions
Author(s): Toshov, Javokhir; Makhmudov, Azamat; Kurbonov, Oybek; Arzikulov, Golib; Makhmudova, Gulnoza
Abstract: Rational and energy efficient operation of pumps for pumping and transporting liquids used in difficult conditions of mining is possible due to the implementation and use of modern methods of managing the operating modes of the pumps. Nowadays, the methods and resources used to regulate the operating modes of pumping units do not meet modern requirements, and many mines still use outdated methods of regulating the operating modes of pumps, which entails significant energy losses and an increase in the cost of the transported liquid. In the article, the methods of reducing electricity losses and the impact on the performance of pumping units were considered. It is concluded that this method of regulating work makes it possible to operate pumping units in the working area. Our article considers and experimentally substantiates the possibility of achieving savings in electrical energy, as well as increasing the reliability of the operation of pumping units based on the use of modern methods of regulating operating modes.2023-01-01T00:00:00ZThe development of sensitive measuring schemes for capacitive-semiconductor humidity transmittersRakhmanov, AnvarKuznetsov, StepanFattoev, Feruzhttps://opendata.uni-halle.de//handle/1981185920/1149642024-01-11T02:08:15Z2023-01-01T00:00:00ZTitle: The development of sensitive measuring schemes for capacitive-semiconductor humidity transmitters
Author(s): Rakhmanov, Anvar; Kuznetsov, Stepan; Fattoev, Feruz
Abstract: Capacitive-semiconductor converters play a crucial role in converting physical quantities with complex
parameters due to their positive properties, including measurement accuracy, reliability, manufacturability,
and efficient measurement schemes. Experimental results and discussions reveal that at small and medium
humidity values (2÷6%), the bridge measuring circuit may not provide the necessary gradation and sensitivity
of the output signal. To address this, a measuring circuit is developed to increase sensitivity and linearize the
output characteristics of the capacitive-semiconductor converter at low and medium humidity values. The
proposed measuring circuit utilizes a bipolar voltage for input value modulation, introducing a new
construction principle for capacitive-semiconductor humidity converters. The measuring scheme enhances
the accuracy and linearity of static characteristics by utilizing bipolar pulses of varying durations. The study
establishes the practical value of pulsed power supply, providing additional opportunities for linearization of
conversion characteristics. The presented results contribute to the development of effective measuring circuits
for capacitive-semiconductor converters, enhancing their metrological characteristics and widening their
applications in monitoring and control systems.2023-01-01T00:00:00ZSteam gas plant reducing circulating water waste in water cooling towersDadaboyev, QobilbekYunusov, Bakhtiyarhttps://opendata.uni-halle.de//handle/1981185920/1149632024-01-11T02:08:35Z2023-01-01T00:00:00ZTitle: Steam gas plant reducing circulating water waste in water cooling towers
Author(s): Dadaboyev, Qobilbek; Yunusov, Bakhtiyar
Abstract: This work is devoted to the calculation of the cooling tower. The explanatory note reflects the material, thermal, hydraulic calculations, guided by which it is possible to select the type of apparatus and its design dimensions. The temperature diagram of the process, the technological diagram of the process, the structural diagram of the apparatus, sketches of the main elements of the apparatus are also shown. The field of velocities of the gas phase, the movement of solid particles, the kinetics of disaggregation of lumps of material, the effect of the concentration of the inert packing and the swirl angle of the coolant on the kinetics of disaggregation of the coolant, was studied experimentally and the choice of the type of inert substance and its concentration was determined. With the help of these techniques how much technical water is saved is also given. In addition, the kinetics of material drying was studied taking into account its disaggregation in a swirling coolant flow.2023-01-01T00:00:00Z