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This paper aims to elaborate the characteristics of magneto-Maxwell nanoliquid toward moving radiated surface. Flow analysis subject to Darcy–Forchheimer concept is studied. Newtonian heat/mass conditions and heat source aspects are taken into account for modeling. Apposite transformations are introduced for non-dimensionalization process.

Optimal homotopy analysis method is implemented to compute convergent solutions of nonlinear ordinary differential equations.

Temperature field increments when thermophoresis, heat generation and Brownian movement parameters are increased, whereas reverse situation is noticed for larger Prandtl number. The results also witness that concentration distribution has opposite characteristics for larger thermophoresis and Brownian movement parameters. Furthermore, the presented analysis reduces to traditional Darcy relation in the absence of local inertia coefficient.

As per the authors’ knowledge, no such analysis has been yet reported.

Nowadays, the determination of the acoustic radiation of electric machines is of particular interest, because legal regulations restrict the maximum audible noise radiated by technical devices such as electrical machinery. The purpose of this paper is to analyze the electromagnetic excited structure‐borne sound and air‐borne noise of an AC servo drive.

This paper presents the required steps for the multiphysics acoustic simulation of electrical machines to evaluate its noise behaviour. This numerical approach starts with the electromagnetic force‐wave simulation. The computation by a structure dynamic model determines the deformation of the mechanical structure due to the force‐waves. The final step of the simulation approach consists of the computation of the acoustic radiation.

For the electromagnetic simulation analytical and numerical methods are combined to gain some acceleration of the entire multiphysics simulation approach. This combination offers additionally a detailed understanding of the noise generation mechanism in electrical machines.

Particular attention is paid to the structural‐dynamic model. Modelling of microstructures, such as the laminated iron core or insulated coils, is memory and computational expensive. A systematic material homogenisation technique, based on experimental‐ and numerical modal analyses, yields a higher accuracy at lower computational costs when compared to standard numerical approaches. The presented multiphysics simulation is validated by measurements. The methods are presented by means of a case study.

The applicability of infra‐red thermography for assessing building façades was studied. Results from the laboratory experiments highlight the importance of the environmental conditions on the accuracy of technique. The thermograms were found effective in showing the simulated anomalies in test samples.

The disinfection robot developed by the authors and team focuses on achieving fast and precise disinfection under a given or specific disinfection zone. This looks to solve problems with traditional robots that pay less attention to the level, efficiency and zones of disinfection. To effectively support and guarantee normal running for the whole system, a digital twin system is applied to the disinfection robot. This study aims to achieve fast, precise and thorough disinfection via the developed mobile robot.

The designed robot is composed primarily of the following three parts: a mobile platform, a six-axis robotic arm and a ultraviolet-C (UVC) LED array. The UVC LED array is installed on the end-effector to achieve large-scale, precise manipulation. The adoption of all types of advanced sensors and the development of an intuitive and user-friendly client interface are helpful in achieving remote control, path planning, data monitoring and custom disinfection functions.

Disinfection of three different locations in the laboratory was performed; the dosage distribution of the surface as radiated by the UVC robot was detected; and feasibility of development was validated.

The developed disinfection robot achieved fast, precise and thorough disinfection for a given or specific disinfection zone.

MANY hold the view that the attainment of very high speeds of flight will be prohibited by the excessive skin temperatures involved, particularly in the vicinity of the wing leading edge, at least until that time when unforeseen advances in metallurgy, or in the application of ceramics, enable the extraordinary problems involved to be overcome. As an opinion it may for all one knows be justified by the event, but it seems (at least to the author) to exaggerate the facts, because it surely ignores the important role played by the conduction of heat along the skin in limiting the temperature. It is the intention of the present article to convert others to this way of thinking.

The paper aims to present the research results related to transparent heating elements made from carbon nanomaterials. Heating elements were fabricated only with cost-effective techniques with the aim to be easily implemented in large area applications. Presented materials and methods are an interesting alternative to vacuum deposition of transparent resistive layers and etching of low-resistive patterns. Fabricated heating elements were designed to be used as de-icing structures in roof-top windows.

The paper presents the research results related to transparent heating elements made from carbon nanomaterials. Heating elements were fabricated only with cost-effective techniques with the aim to be easily implemented in large area applications. Presented materials and methods are an interesting alternative to vacuum deposition of transparent resistive layers and etching of low-resistive patterns. Fabricated heating elements were designed to be used as de-icing structures in roof-top windows.

The sheet resistance of obtained layers was between 9 and 11 kΩ/□; however, double-walled carbon nanotubes showed significantly higher optical transmission (around 70 per cent) than graphene nanoplatelets (around 55 per cent for visible and near infrared range). The amount of polymer resin had the influence on the paints stability, electrical properties and coatings adhesion.

Results show a novel method of fabrication of a large area and transparent heating elements with tunable resistance done through the change of spray coating paint composition.

The paper presents a numerical technique for the simulation of the effects of grey‐diffusive surface radiation on fluid flow using a finite volume procedure for two‐dimensional (plane and axi‐symmetric) geometries. The governing equations are solved sequentially, and the non‐linearities and coupling of variables are accounted for through outer iterations (coefficients updates). In order to reduce the number of outer iterations, a multigrid algorithm was implemented. The radiating surface model assumes a non‐participating medium, semi‐transparent walls and constant elementary surface temperature and radiation fluxes. The calculation of view factors is based on the analytical evaluation for the plane geometry and numerical integration for axi‐symmetric geometry. Ashadowing algorithm was implemented for the calculation of view factors in general geometries. The method for the calculation of view factors was first tested by comparison with available analytical solutions for a complex geometric configuration. The flow prediction code combined with radiation heat transfer was verified by comparisons with analytical one‐dimensional solutions. Further test calculations were done for the flow and heat transfer in a cavity with a radiating submerged body. As an example of the capabilities of the method, transport processes in metalorganic chemical vapour deposition (MOCVD) reactors were simulated.

The purpose of this paper is to validate an assumption of what to use as an effective (steady state) heat transfer coefficient of thermal conductivity for the honeycomb core sandwiched by Fiberglass face sheets composite. A one-dimensional model based on Fourier law is developed. The results are validated experimentally.

The results were obtained from the one-dimensional mathematical model of an overall or effective heat conductivity of the Honeycomb composite panel. These results were validated experimentally by applying heat flux on the specimen under controlled environment. The surface temperatures at different voltages were recorded and analysed. The skin of the sandwich composite material used in the investigation was Fiberglass sheet with a thickness of 0.5 mm at the bottom and 1.0 mm at the top surface. Both skins have a stacking sequence of zero degrees. Due to the presence of air cells in the core (Honeycomb), the model considers the conduction, convection and radiation heat transfer, across the thickness of the panel, combined as an effective conduction mode, whose value may be predicted by using the coefficient of thermal conductivity of the air based on the average temperature difference between the two skins. The experimental results for the heat transfer through the thickness of the panel provide validation of this assumption/prediction. Both infrared thermography and conventional temperature measurement techniques (thermocouples) were used to collect the data.

The heat transfer experiment and mathematical modeling were conducted. The data obtained were analyzed, and it was found that the effective thermal conductivity was temperature-dependent as expected. The effective thermal conductivity of the honeycomb panel was close to that of air, and its value could be predicted if the panel surface temperatures were known. It was also found that as temperature raised the variation between experimental and predicted effective air conduction raised up. This is because there was an increase in molecular diffusion and vibration. Therefore, the convection heat transfer increased at high temperatures and the air became an insulator.

Honeycomb composite panels have excellent physical and thermal properties that influence their performance. This study provides an appropriate method in determining thermal conductivity, which is one of the critical thermal properties of porous composite material. This paper also gives useful and practical data to industries that use or manufacture honeycomb composite panels.

In ultrasonic A‐scan technique the depth and the size of the defect in the material can be determined from the position and amplitude of the reflected echo on the cathode ray tube screen. However, the main difficulty in ultrasonic testing is the precise recognition of the defect type. The purpose of this paper is to develop analysis software to interpret defects of single‐v butt‐welded mild steel plates in ultrasonic testing.

This paper establishes a relationship between types of defects in single‐v butt‐welded mild steel plates and the corresponding amplitudes and widths of echo signals, defect positions and beam directions.

Using this relationship it develops analysis software named “ULTRASL‐1” to predict the type of unknown defects by minimizing the effect of the size and geometry of defect on echo amplitude which is the main limitation in using echo amplitude for identification of defect type.

This paper limits for defects like slag, isolated pore, porosity, lack of inter‐run fusion, lack of side‐wall fusion, crack and lack of penetration in single‐v butt‐welded mild steel plates.

The significance of this work is the introduction of a specialized procedure and a software programme to identify type of defect, so that non‐destructive testing personnel with any level of experience can share the expertise of the best operators in the industry. Hence, it will support to reduce one of the main problems concerning ultrasonic testing, i.e. the difficulties in recognition of defect type.

A study has been undertaken into the use of thermal imaging techniques to determine the temperature distribution of electronic equipment. The suitability of such techniques was investigated to determine the level of confidence that could be established with regard to temperature readings obtained. The study consisted of the comparison of temperatures measured directly using fine wire thermocouples with those obtained from a thermal imaging system. Results showed that surface emissivity was a crucial factor in the determination of accurate temperatures by imaging techniques. However, by coating areas to be studied with a light deposit of aluminium chlorohydrate, a constant highly emissive surface could be obtained. This permitted temperature measurements to be made with an accuracy to within <±1 °C over the temperature range 30° to 90°C. The thermal imaging system was used to study the effect of component colour and of component density on temperature distribution. It was found, with respect to the component spacing, that the maximum component temperature was critically related to the spacing between the devices.