Thermal regime support systems as a component of information systems

Abstract

The prerequisites for creating a system for providing thermal modes of electronic equipment as a necessary component of modern information systems, especially on-board ones, are considered. The release of joule heat is a natural accompaniment to the process of information processing by semiconductor elements. If the core temperature exceeds the permissible limit, the system becomes incapacitated and forced heat removal is an obligatory function of the information system. Building a mathematical model of an information processing system is not a trivial task, including structural and parametric identification aimed at improving reliability and dynamics, it is an urgent task. It is shown that the primary conditions for constructing a mathematical model are information about the nature of the distribution of heat flux in the core, the most important parameter of which is the average temperature of the thermal core of the system. It determines the minimum thermal energy that needs to be selected in order for the system to achieve the nominal thermal conditions of the equipment. Models of the heated zone in the simplest case are considered as isothermal with an average temperature, which is acceptable only for products with a uniform structure. In non-stationary processes, anisotropic heated zones are formed, which are described by corresponding heterogeneous equations in partial derivatives, the solution of which presents significant difficulties. With restrictions given on the parameters, the algorithm for the synthesis of electronic equipment according to the permissible temperature can be obtained based on the solution of the inverse problem of thermal conductivity. The modern mathematical apparatus does not allow us to obtain an analytical solution of the integral equation of the inverse problem of thermal conductivity with an arbitrary law of change in the permissible temperature over the volume of the electronic block. It is shown that one of the possible solutions to the problem of reducing the non-uniformity of heat release in the controlled volume is to provide the heat-loaded elements with drains of the corresponding area, which dissipate heat, bringing their surface temperature closer to the volume average. However, the introduction of wastewater affects the increase in the mass and overall characteristics of electronic systems, which is especially critical for on-board equipment. Requirements to reliability indices of on-board equipment are constantly increasing simultaneously with increase of specific density of heat release by system elements and decrease of weight and dimensions parameters, which is in mutual contradiction and represents scientific and applied problems. Based on the above analysis, it is shown: the average volumetric temperature can serve as a reference basis for systems for ensuring thermal regimes with a fairly uniform arrangement of sources and low spatial anisotropy of thermal conductivity; for systems with heat-loaded elements that differ sharply from the background temperature field, and limitations on weight and size characteristics, the analyzed approaches are unacceptable