SOLUTION OF THE COUPLED THERMOMECHANICAL PROBLEM OF HYDRODYNAMICS FOR DESIGNING THE PROPULSION SYSTEM OF MICROSATELLITES

This paper considers the problem of predicting the technical and operating characteristics of the propulsion system of a microsatellite created by microelectronic technology. The coupled thermomechanical problem of hydrodynamics has been solved by the ANSYS CFX package. The microengine design has been optimized, the heating of its case in the operating time of the fuel chamber has been analyzed, and the velocity field distribution in the microengine nozzle has been determined. The values of the mechanical and temperature deformation fields for pure silicon and a silicon–SiO2 composite have been found, and the possibility in principle of operation of the considered device has been shown. The calculation was made on a triangular net

Mathematical images of learning technology and its action on region

ABSTRACT: The system approach to management of knowledge in region is presented. The main principles of more effective control of knowledge networks is proposed. The effective way to the interactions between learning institutes and the industrial organisations was considered

SOLUTION OF THE COUPLED THERMOMECHANICAL PROBLEM OF HYDRODYNAMICS FOR DESIGNING THE PROPULSION SYSTEM OF MICROSATELLITES

This paper considers the problem of predicting the technical and operating characteristics of the propulsion system of a microsatellite created by microelectronic technology. The coupled thermomechanical problem of hydrodynamics has been solved by the ANSYS CFX package. The microengine design has been optimized, the heating of its case in the operating time of the fuel chamber has been analyzed, and the velocity field distribution in the microengine nozzle has been determined. The values of the mechanical and temperature deformation fields for pure silicon and a silicon–SiO2 composite have been found, and the possibility in principle of operation of the considered device has been shown. The calculation was made on a triangular net

SOLUTION OF THE COUPLED THERMOMECHANICAL PROBLEM OF HYDRODYNAMICS FOR DESIGNING THE PROPULSION SYSTEM OF MICROSATELLITES

Introduction. The universal finite-element gas-dynamic package ANSYS CFX offers developers flexible and effective algorithms for numerical simulation of gas-dynamic and thermophysical processes. This is largely due to the fact that the application of nonstructured finite-element meshes makes it possible to consider the gas dynamics and the heat exchange in multidimensional regions of arbitrary geometry. The above package can also be used to calculate the aerogasdynamics of jet nozzles that is an integral part of the gas dynamics of flows in channels, the theory of aircraft and rocket engines, and the aerodynamics of flying vehicles [1]. It should be noted that the gas flow in jet nozzles in the general case is rather complex (three-dimensional, pulsating, turbulent, with a high temperature, with shocks, with possible detached zones, etc.). For such a flow the basic equations of motion can only be solved numerically, which requires considerable expenditures of time and large RAM capacities of the work station or a cluster. In most cases, this leads to the necessity of using simplified or idealized flow schemes (models) facilitating the description of the gas flow and numerical calculations. In so doing, it is very important to see or determine how adequately these models reflect the real processes in the gas flow, for example, in jet nozzles, and their application in each considered case requires a special thorough analysis and experimental confirmation. Comparison between the calculated and experimental data has shown that in many cases even simple flow models make it possible to adequately describe, in general, the phenomena taking place in jet nozzles Formulation of the Problem. We consider the temperature fields and the stressed-strained state of an assembly of miniature jet nozles made from silicon by the MST technology. The assembly represents a modular construction consisting of identical jet nozzles. The number of elements (separate emgines) in the assembly may vary depending on the technical assignment. Each element is technologically assembled from two identical halves. The computational domain represents a channel of prismatic form with various abrupt junctions, including also junctions with sudden shrinkage. The given form reflects the features of the production process and is far from being ideal in terms of the gas dynamics. −5 m. A test calculation for 6 million elements was carried out. The obtained results differed insignificantly

Biomarkers of early cardiovascular aging

Genetic aspects regulate the intensity and rate of aging (no toxic effects considered), their negative role depends on the pathogenicity of the mutation. The light variant of the genetic “defect” has no clinical signs which feature a certain known genetic syndrome, but it has the biochemical, immunological, vascular and other abnormalities leading to pathological aging. In the most severe case, e.g. progeria, pathological aging is the main phenotypic symptom that manifests already in childhood. The subject of the pathological aging research covers the whole range of intermediate states. The review focuses on aging in individuals without validated signs of disease: coronary heart disease, hypertension, diabetes or fasting hyperglycemia, hyperlipidemia, and others. The authors present the main searching directions of aging biomarkers (size and speed of telomere shortening, breaks in their terminal loops; expression of inflammatory proteins, synaptic interactions proteins and neurotrophic processes; mitochondrial biogenesis; endothelial dysfunction; DNA methylation activity)

Potentiation effect of the AMPK activator A-769662 on cardiac myocytes metabolism and survival

Abstract 286 van Poster session 2 Frontiers in CardioVascular Biology, London 30th March – 1st April 2012 Second Congress of the ESC Council on Basic Cardiovascular Science