Calculation Of The Radiation Temperature Of The Urban Development Environment

The radiation ambient temperature is one of the microclimatic indicators of urban areas, which determines the safe stay of people in them during the warm period of the year. The ability of artificial coatings to accumulate and radiate heat energy should be taken into account in making competent urban planning decisions to eliminate or reduce the additional heat load on the urban environment. The calculation of radiation temperatures of the environment contributes to the adoption of environmentally safe urban planning decisions of specific areas. Using such "tools" as changing the orientation of the urban object to the cardinal directions, thermal properties of anthropogenic coatings, their concentration (density), and exposure, it is possible to control the radiation power of the surrounding surfaces, and, accordingly, the value of radiation temperatures. Research with the use of the globe thermometer confirms change in the radiation temperatures. In this case, the elementary area can be replaced with the reduced site, which will be the limit when calculating the irradiance coefficients of the required accuracy from the elements of urban development. The size of the reduced site is usually a uniform architectural element of the facade plane, for example, the size of a standard window or half of the average wall panel, etc., which is convenient for assigning the materials of the above sites radiation absorption coefficients and calculating or measuring the surface temperature. A method for calculating radiation temperatures, which is based on determining the irradiation coefficients from the globe thermometer to the surrounding fences of an imaginary space (parallelepiped) of the yard, with due regard for their surface temperatures, is proposed.

Broad ion beam-scanning electron microscopy pore microstructure and multifractal characterization of shale oil reservoir: A case sample from Dongying Sag, Bohai Bay Basin, China

Pore structure and its heterogeneity are critical factors controlling the storage capacity and transportation properties of hydrocarbons. Broad ion-beam-milling scanning-electron microscopy allows for the study of a larger planar at high resolution than other methods and can provide insight into shale microstructures. In this study, we investigate the microscopic pore structure of a shale oil reservoir sample from Paleogene Shahejie Formation in Dongying Sag, Bohai Bay Basin, based on the broad ion-beam cross-section, and discuss the heterogeneity of the major pores using multifractal theory. The representative elementary area of the sample was first inferred to be ∼100 × 100 µm2 (25 single images) for the broad ion-beam cross-section with an area of 1.054 × 0.915 mm2. Five pore types (interparticle, intraparticle clay, dissolution, inter-crystalline, and organic) were subsequently identified and analyzed in the selected typical representative elementary area. The results showed that interparticle, intraparticle clay, and dissolution pores were the major pore types and made a significant contribution to the total visible surface porosity (98.34%), whereas inter-crystalline and organic pores were not of great importance. Interparticle pores exhibited the most complex pore morphologies, the largest average pore diameter, and the simplest pore structure. Moreover, interparticle pores that were sub-parallel to the bedding plane showed the best connectivity. Intraparticle clay pores, on the other hand, had the smallest average pore diameter, the most complex pore structure, and their distribution in a two-dimensional plane was the most homogeneous. Dissolution pores were characterized by the least complex pore morphologies but more heterogeneous pore distribution. Both intraparticle clay and dissolution pores were abundant but possessed poor connectivity. We conclude that for shale oil storage and transportation in the Dongying Sag, interparticle pores play an important role in shale oil seepage, whereas intraparticle clay and dissolution pores provide the main space for the occurrence of shale oil.

Efficiency increase in profile deep grinding of turbine blade on NC multi-axes machines

The paper reports the procedure of a cutting mode purpose at deep profile grinding on NC multi-axes machines on the basis of the modeling of thermo-dynamic processes in cutting areas with the purpose of ensuring turbine blade fatigue resistance. There are shown simulators allowing the definition and prediction of the dynamics of elastic, thermal and working processes in a technological system, material removal, cutting force, temperatures in the area of cutting and roughness of each elementary area of the surface profile on the basis of cutting modes, disk characteristics.

A discrete fibre dispersion method for excluding fibres under compression in the modelling of fibrous tissues

Recently, micro-sphere-based methods derived from the angular integration approach have been used for excluding fibres under compression in the modelling of soft biological tissues. However, recent studies have revealed that many of the widely used numerical integration schemes over the unit sphere are inaccurate for large deformation problems even without excluding fibres under compression. Thus, in this study, we propose a discrete fibre dispersion model based on a systematic method for discretizing a unit hemisphere into a finite number of elementary areas, such as spherical triangles. Over each elementary area, we define a representative fibre direction and a discrete fibre density. Then, the strain energy of all the fibres distributed over each elementary area is approximated based on the deformation of the representative fibre direction weighted by the corresponding discrete fibre density. A summation of fibre contributions over all elementary areas then yields the resultant fibre strain energy. This treatment allows us to exclude fibres under compression in a discrete manner by evaluating the tension–compression status of the representative fibre directions only. We have implemented this model in a finite-element programme and illustrate it with three representative examples, including simple tension and simple shear of a unit cube, and non-homogeneous uniaxial extension of a rectangular strip. The results of all three examples are consistent and accurate compared with the previously developed continuous fibre dispersion model, and that is achieved with a substantial reduction of computational cost.

First-order discrete Faddeev gravity at strongly varying fields

We consider the Faddeev formulation of general relativity (GR), which can be characterized by a kind of d-dimensional tetrad (typically d = 10) and a non-Riemannian connection. This theory is invariant w.r.t. the global, but not local, rotations in the d-dimensional space. There can be configurations with a smooth or flat metric, but with the tetrad that changes abruptly at small distances, a kind of “antiferromagnetic” structure. Previously, we discussed a first-order representation for the Faddeev gravity, which uses the orthogonal connection in the d-dimensional space as an independent variable. Using the discrete form of this formulation, we considered the spectrum of (elementary) area. This spectrum turns out to be physically reasonable just on a classical background with large connection like rotations by [Formula: see text], that is, with such an “antiferromagnetic” structure. In the discrete first-order Faddeev gravity, we consider such a structure with periodic cells and large connection and strongly changing tetrad field inside the cell. We show that this system in the continuum limit reduces to a generalization of the Faddeev system. The action is a sum of related actions of the Faddeev type and is still reduced to the GR action.