Selective detection of microcracks under the surface of glass substrates by non-contact stress-induced light-scattering method with temperature variations

Demand for flexible electronics is increasing due to recent global movements related to IoT. In particular, the ultra-thin glass substrate can be bent, its use is expanding for various applications such as thin liquid crystal panels. On the other hand, fine-polishing techniques such as chemical mechanical polishing treatments, are important techniques in glass substrate manufacturing. However, these techniques may cause microcracks under the surface of glass substrates because they use mechanical friction. We propose a novel non-contact thermal stress-induced light-scattering method (N-SILSM) using a heating device for inspecting surfaces to detect polishing-induced microcracks. In this report, we carry out the selective detection of microcracks and tiny particles using a N-SILSM with temperature variation. Our results show that microcracks and tiny particles can be distinguished and measured by a N-SILSM utilizing temperature change, and that microcrack size can be estimated based on the change in light-scattering intensity.

ANALYSIS OF THE HEATING CAPACITY OF ELECTRICALLY HEATED WINDOWS

Electric window heating has been used for some time in Europe and the Americas, but in Ukraine it only enters the market as an independent heating device and raises the question of its heating capacity in winter and the benefits of using them. There are several works in this field that determine the efficiency and contribution to the energy needs of an electric-heated window house, but it is necessary to answer more specifically the question of the heating capacity of such windows as a single heating system, for example rooms of certain sizes.In the work present the design, thermophysical processes occurring in such windows and, by computer simulation of the thermal state of the window with the selected typical room, the results of the study of the heating capacity of the windows, depending on the relative glazing area to the total area of the outer enclosure and the ambient temperature conditions not exceeding the maximum heat emission 450 / and temperature 45 °С on the inner glass of the double-glazed window. the presented thermal model of the window with the room is implemented as a computer program with the possibility of a detailed analysis of the heating capacity of the window, depending on the parameters of the room and the outside temperature, as well as optimization of operational parameters to maintain comfortable conditions.

Tolerable range of abdomen and waist skin temperature for heating-capable smart garments

Purpose This study aims to provide information on how to monitor the temperature setting of a heating device in order to implement a heating unit successfully in the smart clothing by observing voluntary heating behavior of wearers.Design/methodology/approach Subjects wearing base layers and additional clothing were asked to turn on and off the switch when wanted in the cold environmental chamber. Tolerable range of skin temperature (TST) depending on the location of body was obtained by observing the temperature at the time when the heating device was turned on and off during a rest–running–rest protocol.Findings The TST was 32.8–49.4 °C and decreased to 31.3–37.6 °C around abdomen and back waist, respectively. Changes in the wearers' voluntary control behavior were observed depending on the individual's level of cold-sensitivity and activity level of rest and running. TST was 35.8–49.4 °C (Rest 1: rest before exercise), 40.0–42.0 °C (Running) and 35.3–43.2 °C (Rest 2: rest after exercise) for cold-sensitive group, whereas it was 32.8–36.2 °C (Running) and 34.4–45.7 °C (Rest 2: rest after exercise) for cold-insensitive group.Originality/value In this study, results with detailed body locations and wearer's thermal sensitivity provide practical references for the implementation of a heating device to the comfortable multilayered smart clothing.

Improving the environmental friendliness of a solid fuel boiler house using SHF energy

To reduce harmful emissions, solid fuel consumption and increase the efficiency of the boiler plant, an automated system with a combined heating device and a condensing air heater connected in series was designed. In a combined heating device (SHF + flue gases) equipped with a magnetron, quality control and additional preparation of solid fuel with a high moisture content (up to 80%) for combustion are carried out. In the condensing air heater, the heat of the flue gases coming into it from the combined heating deviceand the latent heat of vaporization are extracted. The use of this system allows reducing the moisture content and temperature of flue gases, the volume of harmful emissions from the boiler plant in the form of nitrogen oxides and dioxides (NOx), carbon oxides (CO), ash, volatile coke residues. By increasing the volume and reducing the corrosiveness of the condensate formed from the flue gases in the condensation air heater during the drying process of fuel with a high moisture content, it can be subsequently used as process and make-up water. Practical application of the system makes it possible to reduce the cost of generating heat energy by the boiler house by increasing the use of low-calorie fuel with a high moisture content in the form of waste from logging, wood processing, low-grade coal and peat, which also has a positive environmental effect.

INFLUENCE OF APARTMENTS’ MODERNIZATION ON THE TEMPERATURES OF HEATING SYSTEM IN THE BUILDING

When modernizing apartment buildings, heating appliances are replaced or old ones are left, high thermal temperatures are usually maintained, thus limiting the increase in the DH system’s efficiency. In the article, in order to evaluate the impact of the reduced thermal temperature of the building on space heating when the radiator area remains constant, 3 alternatives have been analyzed. They include cases when after the building modernization old heating appliances are left, but the temperature of the heat carrier is reduced up to 60/40/20 °C in one case or even up to 45/25/20 in another alternative. There has also been examined the possibility of reducing the heat carrier temperature of the heating system without modernization of the building. An hourly data analysis of the heating system model for two typical months of the heating season has been performed. The analysis shows that after the modernization of the building, when heating device areas are left the same, the existing heating temperature can be reduced to 60/40/2020 °C.

An advanced electrical heating technique for double-sided Y(Gd)BCO coated conductor: gaining high engineering current density based on MOCVD

An advanced electrical heating technique was proposed and adopted for the reel-to-reel deposition of double-sided Gd x Y1−x Ba2Cu3O7−δ (Y(Gd)BCO) films on the surface of LaMnO3/epitaxial-MgO/IBAD-MgO/Y2O3/Al2O3/Hastelloy tapes based on the metal organic chemical vapor deposition process. In this technique, heating current is introduced into alloy tape to produce heat through the electric brushes. The use of thin Hastelloy tapes is an effective method to obtain a high engineering current density. However, the reduction of the substrate thickness will directly attenuate its mechanical strength, which will lead to the deformation of tapes at high temperature based on original electric heating device. More seriously, the electrical contact between the alloy substrate and the brush will deteriorate, which could cause ignition and ablation at the edge of the tapes. Therefore, in order to improve mechanical and electrical stability, we redesigned a novel electrical heating device to deposit Y(Gd)BCO films. Furthermore, through adopting the multiple-deposition process based on the new electrical heating device, the J e of Y(Gd)BCO film can reach 900 A mm−2 (at self-field, 77 K), which has been significantly improved compared with the J e before optimization.

Design of an induction brazing installation for connecting oil and gas equipment

The article is devoted to the design of a circuit diagram of an induction heating device. The work carried out a literature review in the area under consideration. The technology of manufacturing a union is considered, which consists of manufacturing a plug, a branch pipe and a flange. Conducted research and application of induction brazing and various fields. Various elements of the equipment used in the design process are considered. A schematic flow diagram of the induction brazing unit has been developed. As a result of the work, the design of the installation for induction soldering was developed and auxiliary materials (flux, solder) were selected.

Equipment for connecting pipeline elements in oil and gas equipment using induction brazing

The article discusses the use of brazing and induction heating for connecting an oil and gas pipeline. The methodology of creating such compounds within the framework of the given problem is considered. The necessary equipment is considered and a schematic diagram of an induction heating device is created, as well as, as a result, a schematic process diagram of an induction soldering device is developed. An analysis and search for all possible solutions to this problem was made, and it was decided to focus on the use of induction soldering. The rationale for the use of induction brazing for such pipeline joints is considered. The application and development of an induction unit is proposed, which allows connecting pipelines for oil and gas equipment in order to increase the durability of the structure during operation at the facility.