Dynamics and forecasting of the Central Asian glaciation and its impact to the projected annual water resources

Abstract HKT-ISTP 2013 B

Optimization of the Cremator Settings for the Disposal of Poultry Waste By Incineration in a Beet-emitting Boiler

The purpose of this work is to substantiate the parameters of the boiler unit, which ensures the cremation of manure using microwave radiation. The substantiation of the amount of heat released during the burning of chicken manure at the industrial keeping of poultry in the conditions of sharply continental climate on the basis of minimization of product utilization values - ash content of wastes and pollution of smoke emissions is presented. Using the obtained regression models of magnetron emission power, moisture content of the burnt manure mass, mass air consumption for the specified product utilization parameters, the analysis of the relationship between the obtained parameters is made. Correlation analysis has shown a high correlation between the amount of heat released during the combustion of manure and the concentration of carbon monoxide in the smoke emissions. Rationally, the value of carbon monoxide content in the flue gases is 3.9%, corresponding to the amount of heat released 2.1 MJ/kg at the combustion of a kilogram of manure at the ash content of the residue of 18.4% and the initial moisture content of the manure of 38.4%. It provides power of radiation of magnetron 400 W on 1 kg of a waste and the mass flow rate of air of 13.8 kg/h

Analysis of promising areas of constructive and technological improvement of units for digging seedlings

The ways to improve the technological process aimed at the digging of various plant species consists of various successive stages. Among them, we can single out the stage of analysis of already existing structural and technological solutions. The article presents an analysis of the directions of development of digging units. The source of information was the open registers of the FIPS of the Russian Federation and foreign databases. During the analysis, the main ways of improving the technological process of digging seedlings and technical solutions for its implementation, as well as ways to achieve a blocked technical result, were identified. Based on the data obtained, a design and technological scheme of the digging bracket has been developed. Further ways of improving the proposed technical solution are outlined

Small-angle X-ray scattering from GaN nanowires on Si(111): facet truncation rods, facet roughness and Porod's law

Small-angle X-ray scattering from GaN nanowires grown on Si(111) is measured in the grazing-incidence geometry and modelled by means of a Monte Carlo simulation that takes into account the orientational distribution of the faceted nanowires and the roughness of their side facets. It is found that the scattering intensity at large wavevectors does not follow Porod's law I(q) ∝ q-4. The intensity depends on the orientation of the side facets with respect to the incident X-ray beam. It is maximum when the scattering vector is directed along a facet normal, reminiscent of surface truncation rod scattering. At large wavevectors q, the scattering intensity is reduced by surface roughness. A root-mean-square roughness of 0.9 nm, which is the height of just 3-4 atomic steps per micrometre-long facet, already gives rise to a strong intensity reduction. open access

Simulation of the Pneumatic System of a Seed Drill with a Vertical Flow Direction

The purpose of the work is to reveal the influence of conical directing agents on the speed and trajectory of particles movement in the vertical pneumatic conduit of the sowing machine and to establish their rational parameters. With the help of numerical modeling the particle flight trajectories in the air flow were obtained. The carried out researches have shown expediency of application of the conical directing agent, allowing to take away a longitudinal stream of particles from walls of a pneumatic conduit and to centre their trajectories of movement along an axis of a pneumatic conduit. Particles are focused to the center of the distributor when the distributor covers the area of pneumatic conduit cross-section close to 25%

Uniformity of the soil tillage depth with tools with disk working bodies

The qualitative parameters of tillage with tools with disk working bodies are influenced by a variety of structural, technological and operational factors. One of these parameters is the uniformity of the depth of tillage, and the influencing factors include the relief of the field, the speed of movement, the method of fastening the working bodies and others. The article presents an overview of the ways of attaching individual disk working bodies to the frame and their effect on the uniformity of the working depth. It is proposed to use a combined statistical method for a more reliable and qualitative assessment of the uniformity of the tillage depth

Assessment of the plume theory predictions of crown scorch using transport models

The aim of our work is to study numerically crown scorch as the effectsof a fire line spreading through surface fuel under a tree canopy. Theobjective was to assess the usual assumptions made when one uses the Van Wagner criteria, which are indeed simple predictive models for crown scorch height, to estimate crown scorch. For this purpose the FIRESTAR 2D and FIRETEC wildfire simulators are used. We simulated the fire line by a heat source at ground level and mainly investigated the temperature field. As a first step, we ran computations of thermal plumes with no-wind and with no canopy, for first comparison to plume theory. The influence of crown existence on the temperature field above the heat source, as well as on crown scorch, was then investigated. As a second step, the effect of a wind to the plume, as well as to crown scorch, was shown for the no-canopy and canopy cases

Comparative analysis of film boiling correlations for steam explosion problem

The article considers the existing models and correlations for describing heat transfer during film boiling. Film boiling is an important thermophysical process that determines the course of interaction of the melt of reactor core materials with the coolant, which can potentially occur during a severe accident at a nuclear power plant with a pressurized water-cooled reactor (VVER/PWR). The values of the Nusselt number predicted by these models are compared. A fairly significant dispersion of calculated parameters has been established, making it difficult to unambiguously choose one or another correlation. However, in the range of parameters typical for the interaction of a high-temperature melt of reactor core materials with a coolant, several correlations give quite close values, which allows them to be recommended for use in calculation codes for modeling thermal-hydraulic processes during a severe accident at a nuclear power plant with VVER/PWR type