Volume 1 Issue 1: March 2022

Article

Computational Investigation of Beryllium and Lithium Performance in Future Fusion Tokamaks

Low-z materials are exemplary candidates in tiling critical plasma-facing components in future fusion reactors due to their low ablation rates under intense high heat fluxes especially during abnormal and hard disruption events. Beryllium and Lithium as low-z materials show good performance as plasma-facing materials in current tokamak. Future tokamaks will exhibit long duration hard disruptions, which in turn requires further investigation of plasma-facing materials, as Li and Be, to judge their performance and evaluate their erosion rates. Electrothermal plasma capillary discharges are used to simulate the high-heat flux deposition on materials to assess their erosion rates. The electrothermal plasma code ETFLOW, which is written for capillary discharges to predict the plasma parameters and erosion rates is used to simulate the high-heat flux conditions similar to expected disruption events for simulated heat fluxes from as low as ~50 to as high as ~290 GW/m2 with a reconnoitering of generating the Be and Li plasmas up to the third ionization (Br+++, Li+++). Performance of Be and Li under the lowest capillary discharge currents (50 kA and 100 kA) is almost identical, however, Li shows sharper increase in the plasma pressure, heat flux, total ablated mass and the exit velocities than Be for higher discharge currents (150, 200 and 250 kA). This huge difference between the performance of Li and Be under low and high heat fluxes can be an important issue for the future magnetic fusion reactors.

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Article

The Thermohydraulic Characteristics Investigation of the Aluminum Alloy Monometallic Plate-finned Tube in Together with Numerical Simulation of Heat and Mass Transfer Processes

The article is devoted to the investigation of aluminium alloy plate-finned tube characteristics regarding to the heat exchange intensification. Outer thick finning, inner ribs quantity and rib shape allow to increase heat exchange efficiency. However, the most important task is finding an optimal combination of pipe geometry parameters. Seven different ribbed tube samples were investigated during the experiment. The samples differed by geometry, quality and quantity of ribbing, and consequently hydraulic and thermodynamic characteristics. The main criteria for an integrated assessment of pressure losses and energy indicators were the criteria of Kirpichev and Antufiev. The above evaluation criteria were intended for an overall assessment of sample effectiveness based on experimental data. In advance and parallel with a natural experiment, a numerical experiment was conducted. The purpose of the numerical experiment was obtaining an adequate model of the heat exchange section to be used in a full-sized oil cooler model in the future. Thus, the article discusses the results of comparing natural and numerical investigations and the prospect of using the best sample in the oil cooler composition. The ultimate goal is the development of an automatic air-cooling apparatus with a compact high-performance oil cooler.

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Review

Geoinformation Systems in the Development of Solar Energy in Turkmenistan

The article considers the scientifically substantiated, systematized solar energy resource potentials of Turkmenistan. Geoinformation technological maps based on solar energy resource potentials for use in Turkmenistan have been developed, compiled. The obtained technical, economic potentials and environmental indicators from the use of power plants based on them have been developed. Solar geoinformation technological maps for the placement of water-lifting plants and solar thermal cells make it possible to increase energy efficiency and environmental safety. The expected environmental and economic effect of the use of solar-energy technological installations in the conditions of the Karakum desert zone is from: reduction of various harmful substances into the environment when selling at a price of 6 US dollars to CO2 carbon fund - 425437.3 tons per year, financial profit will be $ 2.5 million; fossil fuel savings 82.160 thousand tons of fuel equivalent per year or electricity generation of 663.4 GWh per year.

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Communication

The Performance Evaluation of Ventilated Windows in the Simultaneous Improvement of Energy Efficiency and Indoor Air Quality in Office Buildings: A Case Study

Energy efficiency and indoor air quality (IAQ) are two crucial required features in a building. Simultaneous improvement of energy efficiency and IAQ in a building can pave the way for obtaining a green building certification. This paper examined the performance of the airflow windows’ supply and exhaust operating modes in energy-saving and providing IAQ criteria. The analytical zonal model coupled with the airflow network model was used to evaluate the system’s thermal performance and the induced airflow. The simulation was done for an office building located in Shiraz, Iran. The results showed that the energy performance of ventilated windows is positive in nine months of the year. Compared to a conventional double-glazed window, the maximum energy savings is about 10%, which occurs in August. It is predicted that using ventilated windows in office buildings in Shiraz can improve the window’s thermal performance by an average of about 5%. The results also showed that ventilated windows could provide the fresh air needed for the building in 250 days of the year to achieve the desired IAQ index (based on ASHRAE 62.1 standard). Furthermore, the effects of glass aspect ratio, airflow channel thickness, and the size of inlet/outlet openings on energy efficiency and IAQ of the suggested window were studied. Results indicated that in the climatic conditions of Shiraz, the exhaust operating mode is much more efficient than the supply mode.
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