USE OF MONOLITHIC FOAM CONCRETE IN ENCLOSING STRUCTURES OF BUILDINGS AND STRUCTURES WITH VARIABLE THERMAL CONDITIONS

The heat-shielding properties of three-layer external walls insulated with monolithic foam concrete are considered in the article. The temperature is given in rooms operated in intermitt ent heating conditions. An optimal exterior wall design is proposed using monolithic foam concrete for the construction of country cott ages. For this design, the results of heat engineering calculations are presented using the analytical dependence of determining the heat transfer resistance, which ensures the minimum warm-up time of the wall. The results of the calculation are presented in tabular form for a given heating time and density of foam concrete. Also a relationship is described to determine the maximum allowable resistance to heat transfer of the outer wall at diff erent densities of monolithic foam concrete.

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Application of monolithic foam concrete in building envelopes of a cottage, used in conditions of intermittent heating

MATEC Web of Conferences ◽

10.1051/matecconf/201819604015 ◽

2018 ◽

Vol 196 ◽

pp. 04015 ◽

Cited By ~ 1

Author(s):

Yuri Vytchikov ◽

Mikhail Saparev ◽

Vladislav Golikov

Keyword(s):

Specific Energy Consumption ◽

Thermal Characteristics ◽

Outer Wall ◽

Heating Time ◽

Review Literature ◽

Building Envelope ◽

Foam Concrete ◽

Building Envelopes ◽

Insulating Layer ◽

Intermittent Heating

The paper focuses upon the peculiarities of application of monolithic foam concrete as a heat-insulating layer in building envelopes of houses used in conditions of intermittent heating. The researchers analyze thermal characteristics, review literature describing the application of foam concrete in construction and demonstrate this material applicability at outer walls insulating, taking buildings and constructions with variable thermal behaviour as an example. The paper outlines main criteria that building envelopes of such structures should meet. To assess the effectiveness of monolithic foam concrete in building envelopes application, the authors carried out thermo-technical calculation of the outer walls, insulated with monolithic foam concrete. The graphs of dependence of multilayer building envelope heating time upon thickness of a heat-insulating layer and upon heat transmission resistance of the construction was obtained on the basis of these calculations. The dependence of specific energy consumption upon the heating time is also given in the paper. The study reveals the optimal range of thickness and density of monolithic foam concrete for insulating outer walls of buildings, used in in conditions of intermittent heating. This calculation also proves that the application of foam concrete as an insulant on the inside of the outer wall makes it possible to reduce the load on the building foundation.

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Thermal modes simulation of cooling panels in waste water pumping stations

Vestnik MGSU ◽

10.22227/1997-0935.2021.10.1378-1387 ◽

2021 ◽

pp. 1378-1387

Author(s):

Vitaly I. Prohorov ◽

Muhammet A. Razakov

Keyword(s):

Waste Water ◽

Heat Transfer ◽

Mathematical Model ◽

Thermal Conditions ◽

Engineering Calculation ◽

Transfer Coefficients ◽

Pumping Station ◽

Heat Transfer Coefficients ◽

Water Pumping ◽

Functional Areas

Introduction. Authors considers a new method of cooling some functional areas in a city sewage pumping station. They have used the works of Isachenko V.A., Osipov V.A., Sukomel A.S., Bogoslovsky V.N. to simulate the PLI panel’s stationary thermal regime. Materials and methods. Authors have considered the mathematical modeling of stationary and non-stationary thermal phenomena in the PLI panel in this paper. There are the possibilities of modeling the thermal modes of the panel PLI which depending on the place of installation of this device. Authors have given the theoretical characteristics of the heated air in this device and some results of survey in a high voltage urban waste water pumping station in Moscow. There are the heat inputs and heat losses calculations of PLI panel’s various structural elements which carried out using the theory of similarity in this article. Researchers considered the possibility of use other empirical results to determine some of the coefficients which involved in modeling. It has been presented different heat transfer coefficients which could be used in thermal conditions model of PLI panel. There are the validation of the developed models which proved by comparing the deviations in the heat balance equation of the PLI panel. Results. Authors has developed a physical and mathematical model of PLI panel’s thermal modes for a sewage pimping station. Authors have given the recommendations on the possibility of using the different heat transfer coefficients in PLI panel’s thermal conditions modeling process. A numerical experiment was carried out to simulate one PLI panel under the conditions of a sewage pumping station by researchers in this paper. Conclusions. According to the information, this physical and mathematical model can be used for engineering calculation when engineer is selecting the characteristics of PLI panel and also it could be used to clarifying the distributions of heat flow from PLI panel.

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ASSESSMENT OF THERMAL PROTECTIVE CHARACTERISTICS OF WELL MASONRY WITH THE USE OF NO-FINE EXPANDED-CLAY LIGHTWEIGHT CONCRETE

URBAN CONSTRUCTION AND ARCHITECTURE ◽

10.17673/vestnik.2019.01.3 ◽

2019 ◽

Vol 9 (1) ◽

pp. 15-19

Author(s):

Yury S. VYTCHIKOV ◽

Mikhail E. SAPAREV ◽

Andrey S. PRILEPSKY ◽

Darya D. KONYAKINA

Keyword(s):

Heat Transfer ◽

Lightweight Concrete ◽

Engineering Calculation ◽

Temperature Fields ◽

Thermal Engineering ◽

Transfer Resistance ◽

Heat Engineering ◽

Energy Efficient Buildings ◽

Engineering Technique ◽

Original Construction

As part of the implementation of programs for the resettlement of dilapidated housing and rural construction, special attention is paid to the construction of low rise energy efficient buildings. Analysis of various technologies for the construction of low rise buildings revealed the feasibility of using expanded clay concrete as a structural and insulating material in three layer exterior walls and well laying. The presented heat engineering calculation of the original construction of the well masonry showed rather high values of the reduced heat transfer resistance and the coefficient of heat engineering uniformity. Rather high accuracy of the presented engineering technique of thermal engineering calculation is confirmed by comparison of the received data on resistance to heat transfer of an external wall by the approximate analytical method with data of computer simulation of temperature fields by a finite element method.

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DETERMINATION OF HEAT TRANSFER RESISTANCE IN NON-STATIONARY THERMAL CONDITIONS

Vestnik Tomskogo gosudarstvennogo arkhitekturno-stroitel nogo universiteta JOURNAL of Construction and Architecture ◽

10.31675/1607-1859-2020-22-6-83-93 ◽

2020 ◽

Vol 22 (6) ◽

pp. 83-93

Author(s):

A. N. Belous ◽

G. A. Kotov ◽

D. A. Sapronov ◽

B. A. Novikov

Keyword(s):

Heat Transfer ◽

Real Estate ◽

Thermal Characteristics ◽

Thermal Conditions ◽

Full Scale ◽

Transfer Resistance ◽

Advantages And Disadvantages ◽

Fundamental Research ◽

Cis Countries ◽

Resistance To Heat

One of the main normalized heat engineering indicators of enclosing structures is the resistance to heat transfer. On the territory of the CIS countries there are a huge number of real estate objects designed and built in accordance with outdated standards for the consumption of heat energy for heating and ventilation, requirements for the heat-protective shell of buildings, which leads to energy overspending. All real estate objects put into operation before the tightening of the above-mentioned standards require determining the actual thermal characteristics of the enclosing structures and bringing them into compliance with the current legislation. The article analyzes existing methods for determining the heat transfer resistance of enclosing structures in full-scale conditions, and identifies the advantages and disadvantages of these methods. Based on the fundamental research of construction Thermophysics, a mathematical model for determining the resistance to heat transfer in full-scale conditions is proposed, taking into account the shortcomings of existing methods.

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OPTIMIZATION OF HEAT PROTECTION CHARACTERISTICS OF COUNTRY COTTAGE ENCLOSURES

URBAN CONSTRUCTION AND ARCHITECTURE ◽

10.17673/vestnik.2021.01.5 ◽

2021 ◽

Vol 11 (1) ◽

pp. 39-45

Author(s):

Yuri S. VYTCHIKOV ◽

Mikhail E. SAPAREV ◽

Vladislav A. GOLIKOV ◽

Evgeniy G. SAFRONOV

Keyword(s):

Heat Transfer ◽

Energy Consumption ◽

Thermal Protection ◽

Minimum Energy ◽

Thermal Conditions ◽

Outer Wall ◽

Wall Material ◽

Transfer Resistance ◽

Heating Systems ◽

Minimum Energy Consumption

The article presents a method for determining the minimum permissible value of the heat transfer resistance of the outer wall, at which the minimum energy consumption is achieved during the operation of buildings with variable thermal conditions. A review of the sources devoted to this problem showed the presence of high costs of thermal energy during the heating of premises. On the basis of studies of all components of energy consumption in the operation of premises with intermitt ent heating systems, the authors of the article propose a method for determining the minimum permissible resistance to heat transfer, which provides minimum energy consumption. According to the described method, the calculation was made for external walls made of various materials. The analysis of the obtained results showed that a signifi cant infl uence on the minimum permissible value of the heat transfer resistance is exerted by a complex of thermophysical values cρλ. The presented graphical dependence R0 усл on the complex cρλ allows the designer to rationally choose a wall material that provides a minimum of energy consumption during the operation of the building. In the context of rising energy tariff s, such optimization of thermal protection characteristics is especially important for country cott ages operated in intermitt ent heating conditions.

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Cooling of a battery pack of a car, working on renewable energy

MATEC Web of Conferences ◽

10.1051/matecconf/201824515003 ◽

2018 ◽

Vol 245 ◽

pp. 15003 ◽

Cited By ~ 5

Author(s):

Ivan Kasatkin ◽

Mikle Egorov ◽

Evgeny Kotov ◽

Evgeny Zakhlebaev

Keyword(s):

Heat Transfer ◽

Heat Dissipation ◽

Heat Removal ◽

Lithium Ion ◽

Operating Mode ◽

Engineering Calculation ◽

Electrical Circuit ◽

Thermal Engineering ◽

Air Cooling ◽

Forced Air

The aim of the work is to choose a method of a solar car battery cooling. The student engineering team of Peter the Great Petersburg Polytechnic University designs the car. The analysis of the electrical circuit of the battery is carried out, the heat release is estimated due to three factors. According to the conditions of reliable operation of the battery, it is necessary to maintain its temperature range below 45°C, which requires cooling. The paper analyzes the possibilities of liquid, air-cooling, compares the free and forced methods of convective heat transfer. For the normal operating mode of the electric vehicle, environmental temperature at the level up to 38°C, a criterion thermal engineering calculation of the forced air-cooling of the corridor assembly of 405 battery cells providing the required heat dissipation is performed. It is shown that relatively high values of the heat transfer coefficient are provided under turbulent flow conditions characterized by Reynolds criteria above 103. On the basis of an analysis of the steady-state stationary heat-removal regime, it was concluded that an air flow provides a temperature gradient, sufficient for cooling the lithium-ion battery of a Solar Car «Polytech Solar».

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Evolution of regulations for thermal protection of buildings

Архитектура и дизайн ◽

10.7256/2585-7789.2021.1.35796 ◽

2021 ◽

pp. 33-44

Author(s):

Lyubov' Vyacheslavovna Ivanova

Keyword(s):

Heat Transfer ◽

Thermal Protection ◽

Thermal Engineering ◽

Regulatory Documents ◽

The Past ◽

Normative Requirements ◽

Standard Documentation ◽

Building Heat ◽

Resistance To Heat ◽

Qualitative Changes

The article is devoted to the study of regulatory documents in the field of thermal engineering in construction and the development of regulations for thermal protection of buildings. The object of the research is the standard documentation in the field of thermal engineering in construction. A retrospective analysis of the norms and requirements for thermal protection of buildings was carried out by identifying qualitative changes in the content of standard documentation. Building codes and regulations, Code specification, Federal laws and Government decrees have been adopted as such regulatory documents for this study. The documents that influenced these changes are considered. The normative requirements of the past years in the field of building heat engineering have been systematized. Six stages of the formation of norms for the thermal protection of buildings are determined, based on changes in the formulas for determining the resistance to heat transfer of enclosing structures and the introduction of the characteristic of the degree-day of the heating period, depending on the climatic features of the region. Trends in the development of standards for thermal protection of buildings have been determined. The main goal is to reduce the specific characteristic of heat energy consumption for heating and ventilation, which requires a change in the requirements for thermal protection, in particular, an increase in the required resistance to heat transfer, which can contribute to updating the existing set of rules for thermal protection of buildings.

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Numerical Simulation Study on Supercritical Natural Circulation Flow and Heat Transfer in Narrow Rectangular Channels

Volume 4: Thermal Hydraulics ◽

10.1115/icone21-15576 ◽

2013 ◽

Author(s):

Mingqiang Song ◽

Tao Zhou ◽

Jingjing Li ◽

Juan Chen ◽

Wanxu Cheng ◽

...

Keyword(s):

Heat Transfer ◽

Supercritical Water ◽

Subcritical Water ◽

Natural Circulation ◽

Fluid Velocity ◽

Engineering Calculation ◽

Thermal Engineering ◽

Ansys Cfx ◽

Rectangular Channels ◽

Study Parameter

When the model of natural circulation in vertical rectangular channels with gap 1 mm was created, considering the character of supercritical water, the distribution of fluid velocity, temperature and density were obtained with the help of ANSYS CFX. The conclusion is that supercritical density is much lower than that of subcritical water in this study parameter and that the heat transfer ability of supercritical water is higher than that of subcritical water. Futuremore, narrow rectangular channels contribute supercritical fluid to transfer heat, which lay the foundation of accurate supercritical thermal engineering calculation.

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Evolution of regulations for thermal protection of buildings

Архитектура и дизайн ◽

10.7256/2585-7789.2020.1.35796 ◽

2020 ◽

pp. 33-44

Author(s):

Lyubov' Vyacheslavovna Ivanova

Keyword(s):

Heat Transfer ◽

Thermal Protection ◽

Thermal Engineering ◽

Regulatory Documents ◽

The Past ◽

Normative Requirements ◽

Standard Documentation ◽

Building Heat ◽

Resistance To Heat ◽

Qualitative Changes

The article is devoted to the study of regulatory documents in the field of thermal engineering in construction and the development of regulations for thermal protection of buildings. The object of the research is the standard documentation in the field of thermal engineering in construction. A retrospective analysis of the norms and requirements for thermal protection of buildings was carried out by identifying qualitative changes in the content of standard documentation. Building codes and regulations, Code specification, Federal laws and Government decrees have been adopted as such regulatory documents for this study. The documents that influenced these changes are considered. The normative requirements of the past years in the field of building heat engineering have been systematized. Six stages of the formation of norms for the thermal protection of buildings are determined, based on changes in the formulas for determining the resistance to heat transfer of enclosing structures and the introduction of the characteristic of the degree-day of the heating period, depending on the climatic features of the region. Trends in the development of standards for thermal protection of buildings have been determined. The main goal is to reduce the specific characteristic of heat energy consumption for heating and ventilation, which requires a change in the requirements for thermal protection, in particular, an increase in the required resistance to heat transfer, which can contribute to updating the existing set of rules for thermal protection of buildings.

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