scholarly journals Series of Experiments with Thermal Insulation Coatings Consisted of Vacuum-Hollow Nano-Ceramic Microspheres

2018 ◽  
Vol 11 (1) ◽  
pp. 17-33
Author(s):  
David Bozsaky
Keyword(s):  
Heat Transfer ◽  
Thermal Insulation ◽  
Convective Heat Transfer Coefficient ◽  
Ceramic Coatings ◽  
Complete Agreement ◽  
Transfer Resistance ◽  
Structured Materials ◽  
Thermal Insulating ◽  
Series Of Experiments

Because of the rigorous regulations in the 21st century it has become a serious task for designers to find more effective ways for thermal insulation. One of these options is the application of nanotechnology-based materials. Among nano-scale structured materials the most uncertainties are found about the thermal insulating quality of thermal insulation coatings consisted of vacuum-hollow nano-ceramic microspheres. Complete agreement had not been already found about the mechanism of their insulating effect. In order to explore and describe the thermodynamic process inside nano-ceramic coatings (NCC) 6 series of heat transfer resistance experiments were performed in 2014-2017. Several building structure configurations with 12 different orders of layers were tested with a standard heat flow meter. On basis of these results it could be concluded that in case of nano-structured materials convective heat transfer coefficient might be taken account in different way than in case of traditional macro-structured thermal insulation materials.

scholarly journals EFFECTIVE HEAT-PROTECTIVE SYSTEM WITH THE USE OF THERMAL INSULATING SOLUTION OF REDUCED DENSITY

2019 ◽  
Vol 16 (3) ◽  
pp. 323-333
Author(s):  
L. Kh. Zagorodnyuk ◽  
D. A. Sumskoy ◽  
S. V. Zolotykh
Keyword(s):  
Heat Transfer ◽  
Thermal Insulation ◽  
Raw Materials ◽  
Field Tests ◽  
Ecological Effect ◽  
Laboratory Research ◽  
Low Density ◽  
Actual Problem ◽  
Transfer Resistance ◽  
Thermal Insulating

Introduction. The manuscript is devoted to the actual problem of thermal insulation of buildings and structures. The paper presents a developed low-density insulation solution with improved heatengineering characteristics. The aim of the work is to increase the efficiency of the heat-shielding system using a low-density heat-insulating solution.Methods and materials.The authors carried out tests at the site of heat engineering control of LLC «Intellect-service-ZBK-1» to determine the resistance to heat transfer of the enclosing structure.Results.The construction of the wall system consisting of the «Aerobel» D500 gas-silicate block (625×200×250 mm) and made on a low-density heat-insulating masonry mortar, as well as with the use of a heat-insulating mortar and a universal «Moutrical» energy-efficient coating allowed increasing actual reduced heat transfer resistance from 0.9 to 1.4 (m2 ·K) / W (by 36%).Discussion and conclusions.Laboratory research and field tests that meet the requirements of state standards and that develop low-density heat-insulating plaster demonstrate the low-density heatinsulating solution, which indicates the feasibility in thermal insulation of buildings and structures. The authors achieve special economic and ecological effect in connection with the use of local raw materials and waste production of expanded perlite sand.

scholarly journals Moisture Behavior of Thermal Insulation Coating Consisted of Vacuum-Hollow Nano-Ceramic Microspheres

2018 ◽  
Author(s):  
Dávid Bozsaky
Keyword(s):  
Thermal Insulation ◽  
Material Properties ◽  
Time Trend ◽  
Ceramic Coatings ◽  
Building Industry ◽  
Mathematical Connections ◽  
Thermal Insulating ◽  
Insulation Coating ◽  
Insulation Quality ◽  
Thermodynamic Processes

Nanotechnology-based thermal insulation materials have appeared in building industry in the last two decades. Among them thermal insulating coatings consisted of vacuum-hollow nano-ceramic microspheres are the subjects of most professional discussion. Most studies about these coatings focus only on examination of thermodynamic properties, because there is still no consensus in academic circles about thermodynamic processes inside nano-ceramic coatings. These professional discussions distract attention from other unknown but also important material properties, like behavior by contact with moisture. This paper summarizes the results of moisture behavior tests with nano-ceramic thermal insulation coatings which were conducted to determine the time trend of water absorption, as well as volume, mass and thermal insulation quality changes caused by increasing moisture content. Analyzing the results mathematical connections were found to describe the relation between water content, dimensional and thermal conductivity changes.

The Cause Detection and Analysis of the Surface Cracks on ETIRS

2011 ◽  
Vol 71-78 ◽  
pp. 4533-4539
Author(s):  
Ju Gang Luo
Keyword(s):  
Thermal Insulation ◽  
Basic Concept ◽  
Structure Design ◽  
Expanded Polystyrene ◽  
Surface Cracks ◽  
Insulation System ◽  
Construction Quality ◽  
Thermal Insulating ◽  
Insulation Wall

The cause detection and analysis have been made over the surface cracks of external thermal insulating rendering systems made of mortar with bonding powder and using expanded polystyrene granule as aggregate (ETIRS) by means of integrating the basic concept of the cracks and actual project practices, on the basis of structure design, materials performances and construction. The result shows that the major causes for surface cracks, the hazardous ones are caused by poor construction quality. In order to guarantee the quality of external thermal insulation wall, the structure design of the said thermal insulation system shall be underlined and building quality on the key parts, stressed.

A Heat Transfer Study in the Head Disk Interface and an Insight to Heat Assisted Magnetic Recording Design

2017 ◽  
Author(s):  
Haoyu Wu ◽  
David Bogy
Keyword(s):  
Heat Transfer ◽  
Magnetic Recording ◽  
Convective Heat Transfer Coefficient ◽  
Head Disk Interface ◽  
Heat Assisted Magnetic Recording ◽  
Disk Interface ◽  
Height Control ◽  
Contact Sensor ◽  
Series Of Experiments ◽  
Fly Height

Understanding the heat transfer in the head disk interface (HDI) in the heat assisted magnetic recording (HAMR) is important. In this paper, we report on a series of experiments to study the heat transfer in the HDI using the perpendicular magnetic recording (PMR) heads and media. The temperature increase of the embedded contact sensor (ECS) and the thermal fly-height control (TFC) heater was compared in the fly setup and non-fly setup. A series of simulations were performed to explain the results. We show that the design of the air bearing surface can significantly affect the pressure distribution in the read/write transducer area, and thereby affect the convective heat transfer coefficient.

Research on Heat Transfer and Calculation Method of Workpiece Surface Temperature in High Speed Grinding

2011 ◽  
Vol 325 ◽  
pp. 28-34
Author(s):  
Bei Zhi Li ◽  
Da Hu Zhu ◽  
Zhen Xin Zhou ◽  
Jing Zhu Pang ◽  
Jian Guo Yang
Keyword(s):  
Heat Transfer ◽  
Surface Temperature ◽  
High Speed ◽  
Removal Rate ◽  
Convective Heat Transfer Coefficient ◽  
Calculation Model ◽  
Grinding Wheel ◽  
Workpiece Surface ◽  
High Speed Grinding

The surface quality of workpiece depends largely on workpiece surface temperature in grinding. The key parameters on workpiece surface temperature calculation model have been researched and the calculation model constructed in this paper, including the convective heat transfer coefficient (CHTC) (hf), heat flux (qch) and the grain contact half-width (r0) which are assumed to be constant in workpiece surface temperature model given by Rowe. And the improved Rowe model has been proposed (Rowe/Li model) which not only involves the grinding process parameters such as the speed of wheel and workpiece, but also the geometric parameters of workpiece, grinding wheel and abrasive. The experimental results of the surface temperature in high-speed grinding are very close to the results by Rowe / Li model. Relative to the Rowe model, the obtained surface temperature by Rowe / Li model has decreased by about 35-40%. Under the conditions of the same material removal rate, high-speed grinding, namely, increasing wheel speed can effectively reduce the surface temperature and improve the grinding quality.

Sign in / Sign up

Export Citation Format

Share Document