Questions of thermoregulation in heatstressed composite systems with mesh screens

10.12737/1780 ◽  
2013 ◽  
Vol 3 (3) ◽  
pp. 156-160
Author(s):  
Ерин ◽  
Oleg Erin ◽  
Попов ◽  
Viktor Popov ◽  
Кондратенко ◽  
...  
Keyword(s):  
Thermal Resistance ◽  
Metal Surfaces ◽  
Thermal Conditions ◽  
Metal Wire ◽  
Contact Thermal Resistance ◽  
Composite Systems ◽  
Intensive Development

In connection with the intensive development of new areas of technology, where heat-stressed systems are widely represented, there is urgent need of directed thermoregulation. To control the thermal conditions in composite systems it is required, in particular, to create connections with good insulation. The problem of increasing contact thermal resistance between the metal surfaces by introducing of mesh screens made of metal wire into the zone section is examined on condition the application of small loads not exceeding 1 MPa.

Contact heat exchange in conjunction with metal surfaces which have deviations in form or waviness

2015 ◽  
Vol 5 (4) ◽  
pp. 234-241
Author(s):  
Ерин ◽  
Oleg Erin ◽  
Кондратенко ◽  
Irina Kondratenko ◽  
Попов ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Thermal Resistance ◽  
Metal Surfaces ◽  
Calculated Data ◽  
Contact Thermal Resistance ◽  
Contact Heat ◽  
Mechanical Loads ◽  
Physical Experiments ◽  
Contact Heat Exchange ◽  
Constituent Elements

In the design of thermally stressed units in the sectors of mechanical engineering, aviation, aerospace, energetics it is often necessary to have information about the formation of the contact thermal resistance resulting from the discrete nature of parts metal surfaces contacting. While passing through the section zones of heat flows the temperature gradient increases, thus reducing the heat transfer capability of the contact junction and leads to thermal expansion of the constituent elements of the systems, relative shifts and warpages. The process of heat transfer through the zone of contact between metal surfaces having deviation of shapes in the form of nonflatness or waviness under conditions suitable to small mechanical loads is considered. The model of formation of the contact thermal resistance (CTR), in case of double contraction of the heat flow of channel and contact mаcrospots, caused by nonflatness or waviness, and then to microspots caused by roughness. Subject to the provisions of the theory of mechanical contacting of solids theoretical curves is derived describing the contact thermal resistance for compounds with surfaces having microdeviation or waviness operating in the regime of small mechanical loads. The results of physical experiments give satisfactory agreement with the calculated data. It was established that the presence of nonflatness or waviness on the contact surfaces increases CTR significantly as compared with rough surfaces. Increase of CTR is explained by the increase of wave height or equivalent nonflatness

Evaluation of a permissible roadbed thawing depth in permafrost

2021 ◽  
Vol 5 ◽  
pp. 18-22
Author(s):  
Alexandr Galkin
Keyword(s):  
Thermal Resistance ◽  
Biot Number ◽  
Seasonal Changes ◽  
Construction Materials ◽  
Thermal Conditions ◽  
Road Base ◽  
Thawing Depth ◽  
Roadway Construction ◽  
Selection Of ◽  
Purpose Of Evaluation

Roadbed thermal conditions in permafrost are subject to seasonal changes affecting roadway resilience. A roadbed thawing depth is important for road base processing, especially in permafrost. This research had the purpose of evaluation of a permissible roadbed thawing depth based on the Biot number reflecting general thermal resistance of roadbed layers. These results will contribute to understanding road bed thermal resistance and selection of roadway construction materials.

Thermal resistance of contact with oxidized metal surfaces

1973 ◽  
Vol 25 (4) ◽  
pp. 1292-1297
Author(s):  
V. M. Popov ◽  
A. I. Krasnoborod'ko
Keyword(s):  
Thermal Resistance ◽  
Metal Surfaces

scholarly journals The inverse coefficient problem of heat transfer in layered nanostructures

2017 ◽  
Vol 20 (3) ◽  
pp. 213-219
Author(s):  
K. K. Abgarian ◽  
R. G. Noskov ◽  
D. L. Reviznikov
Keyword(s):  
Heat Transfer ◽  
Inverse Problem ◽  
Thermal Resistance ◽  
Transfer Problem ◽  
Dominant Role ◽  
Rapid Development ◽  
Problem Solution ◽  
Microwave Range ◽  
Contact Thermal Resistance ◽  
Resistance Coefficients

The rapid development of electronics leads to the creation and use of electronic components of small dimensions, including nanoelements of complex, layered structure. The search for effective methods for cooling electronic systems dictates the need for the development of methods for the numerical analysis of heat transfer in nanostructures. A characteristic feature of energy transfer in such systems is the dominant role of contact thermal resistance at interlayer interfaces. Since the contact resistance depends on a number of factors associated with the technology of heterostructures manufacturing, it is of great importance to determine the corresponding coefficients from the results of temperature measurements.The purpose of this paper is to evaluate the possibility of reconstructing the thermal resistance coefficients at the interfaces between layers by solving the inverse problem of heat transfer.The complex of algorithms includes two major blocks — a block for solving the direct heat transfer problem in a layered nanostructure and an optimization block for solving the inverse problem. The direct problem was formulated in an algebraic (finite difference) form under the assumption of a constant temperature within each layer, which is due to the small thickness of the layers. The inverse problem was solved in the extreme formulation, the optimization was carried out using zero-order methods that do not require the calculation of the derivatives of the optimized function. As a basic optimization algorithm, the Nelder—Mead method was used in combination with random restarts to search for a global minimum.The results of the identification of the contact thermal resistance coefficients obtained in the framework of a quasi-real experiment are presented. The accuracy of the identification problem solution is estimated as a function of the number of layers in the heterostructure and the «measurements» error.The obtained results are planned to be used in the new technique of multiscale modeling of thermal regimes of the electronic component base of the microwave range, when identifying the coefficients of thermal conductivity of heterostructure.

scholarly journals Contact thermal resistance of capillary structures of heat pipes in heat-exchange systems of spacecrafts and helioenergetics

2009 ◽  
Vol 15 (1) ◽  
pp. 75-79
Author(s):  
A.G. Kostornov ◽  
◽  
A.A. Shapoval ◽  
G.A. Frolov ◽  
I.V. Shapoval ◽  
...  
Keyword(s):  
Heat Exchange ◽  
Thermal Resistance ◽  
Heat Pipes ◽  
Contact Thermal Resistance
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