Predictive 3D modelling of erosion and deposition in ITER with ERO2.0: from beryllium main wall, tungsten divertor to full-tungsten device

Erosion and deposition is modelled with ERO2.0 for a hypothetical full-tungsten ITER for an ELM-free H-Mode baseline deuterium discharge. A parameter study considering seeding impurities (Ne, Ar, Kr, Xe) at constant percentages (0.05% to 1.0%) of the deuterium ion flux is done while neglecting their radiation cooling and core plasma compatibility. With pure deuterium plasma, tungsten main wall erosion is only due to charge exchange deuterium atoms and self-sputtering and there is only minor tungsten divertor sputtering. With a beryllium main wall, beryllium erosion is due to deuterium ions, charge exchange deuterium neutrals and self-sputtering. For this case, tungsten in the divertor is eroded by beryllium ions and self-sputtering. The simulations for full-tungsten device including seeded impurities leads to significant tungsten erosion in the divertor. In general, tungsten erosion, self-sputtering and deposition increase by factors larger than 50 at the main wall and 5000 in the divertor compared to pure deuterium plasma

Microclimatic features of landscapes in the territory with a sparse network of meteorological observations

Automatic monitoring of air temperature and humidity in the mountain-depression landscapes of the Tunka depression has been organized. The results of the analysis of observation data for 10 years showed significant differences in the temperature regime in different landscapes. The sites can be divided into three groups – the slopes of the depression, pine- herbaceous landscapes, and the lacustrine-bog complex of the central part. The average annual air temperature at all sites is negative and vary in range -0.7 … -2.1°C. Vegetation has the greatest influence on microclimatic characteristics. The maximum contrasts in the temperature regime of the air throughout the year are observed in open areas with cloudless skies. In winter, this is explained by radiation cooling, and in summer – by the heating of the open surface in the daytime. In this case, not only the daily amplitude of air temperature in the open areas increases, but also the largest contrasts between the open and closed areas are observed.

Effective Properties of Semitransparent Radiative Cooling Materials With Spectrally Variable Properties

Radiation cooling is a promising solid-state, non-vapor-compression technology for passive refrigeration and air conditioning. Although this phenomenon occurs naturally, achieving a significant amount of cooling to make it a technically and economically viable technology requires highly engineered, spectrally selective radiative surfaces. These characteristics make radiation cooling difficult to estimate, particularly when it is integrated with other systems such as photovoltaic panels or building envelopes. The complexity further increases when the substrate also participates in the radiative cooling (along with the radiative coating). Energy estimation is becoming increasingly critical because of the recent focus on the semitransparent radiative coatings that transmit a variety of colors to enhance the aesthetic appeal of the system. Here, we propose a simple iterative method to calculate the effective radiative properties, which provide the same net radiative cooling that would be observed using the spectral properties at both the coating and substrate surfaces. Compared to traditional methods that rely on either computationally expensive full spectral analysis or methods for averaging each radiative surface parameter locally, our proposed method focuses on calculating effective properties that provide the same the net cooling effect as a full spectral analysis by accounting the emissivity, absorptivity, and transmissivity collectively, thereby providing an overall estimation error of less than 0.2%. We believe that this study will be beneficial to the engineering communities that employ complex simulation codes and require lumped solar and thermal radiation related parameters.

Numerical Simulation on Cooling Effect of Working Face under Radiation Cooling Mode in Deep Well

Deep mining results in an increasingly serious hazard. Based on the principle of heat transfer and radiant cooling, a three-dimensional heat transfer model of the working face was established. The influence of the inlet airflow parameter, the surrounding wall temperature and other parameters on the temperature distribution of airflow along the working face were analyzed under the radiation cooling mode. The results show that the increment of airflow temperature in several sections along the working face decreases by 0.67 °C, 0.48 °C, 0.40 °C, 0.36 °C, 0.33 °C, 0.29 °C respectively. The farther away from the airflow inlet, the more obvious the cooling effect was. The airflow temperature of the working face is positively correlated with the airflow inlet temperature and the surrounding wall temperature, and is negatively correlated with the airflow velocity. The research provides a good solution for the working face cooling of deep mines, and also provides a theoretical reference for the research on the radiation cooling technology of the working face.