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This study aims to evaluate the thermal performance of sodium alginate (SA) aerogel attached to nano SiO₂ and its radiative cooling effect on firefighting clothing without environmental pollution.

SA/SiO₂ aerogel with refractory heat insulation and enhanced radiative cooling performance was fabricated by freeze-drying method, which can be used in firefighting clothing. The microstructure, chemical composition, thermal stability, and thermal emissivity were analyzed using Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analyzer and infrared emissivity measurement instrument. The radiative cooling effect of aerogel was studied using thermal infrared imager and thermocouple.

When the addition of SiO₂ is 25% of SA, the prepared aerogel has excellent heat insulation and a high radiative cooling effect. Under a clear sky, the temperature of SA/SiO₂ aerogel is 9.4°C lower than that of pure SA aerogel and 22.1°C lower than that of the simulated environment. In addition, aerogel has more exceptional heat insulation effect than other common fabrics in the heat insulation performance test.

SA/SiO₂ aerogel has passive radiative cooling function, which can efficaciously economize global energy, and it is paramount to environment-friendly cooling.

This method could pave the way for high-performance cooling materials designed for firefighting clothing to keep maintain the wearing comfort of firefighters.

SA/SiO₂ aerogel used in firefighting clothing can release heat to the low-temperature outer space in the form of thermal radiation to achieve its own cooling purpose, without additional energy supply.

The purpose of this paper is to investigate if the fibers obtained from chicken feathers have a possibility to be used or not used in Winter outerwears as a filling material in terms of thermal insulation parameters.

In the study, thermal properties of the heat-resistant interlining samples produced from the chicken feathers fibers were analyzed in comparison with the samples produced from the industrial filling materials.

In the study, it was revealed that the use of chicken feathers fibers as filling material in Winter outerwears was possible.

The use of chicken feather fibers in Winter outerwears as a filling material will be an extremely low-cost alternative to pile flies of water birds which are sufficiently expensive filling materials.

A significant portion of the chicken feather, which is released as a by-product in the production of chicken meat, is destroyed as industrial waste by digging or burning. Some of this product is used in the production of such cheap products as poultry feed. In the case of the production of fibers from the chicken feather, the use of these fibers as a filler in Winter clothing along with environmental protection will allow the use of this product for the production of products of higher cost.

The use of feathers’ material as a filling material in Winter outerwears has been known since ancient times. Due to the rough structure and low elasticity of chicken feathers, chicken feathers are not the best raw material for this purpose. This study revealed that it is possible to use chicken feathers as a filling material in terms of heat protection. The study is original in this respect.

Insulation materials’ contribution to the fire resistance of timber frame assemblies may vary considerably. At present, Eurocode 5 provides a model for fire design of the load-bearing function of timber frame assemblies with cavities completely filled with stone wool. Very little is known about the fire protection provided by other insulation materials. An improved design model which has the potential to consider the contribution of any insulation material has been introduced by the authors. This paper aims to analyze the parameters that describe in a universal way the protection against the charring given by different insulations not included in Eurocode 5.

A series of model-scale furnace tests of floor specimens for three different insulation materials were carried out. An analysis on the charring depth of the residual cross-sections was conducted by means of a resistograph device.

The study explains the criteria and procedure followed to derive the coefficients for the improved design model for three insulations involved in the study.

This research study involves a large experimental work which forms the basis of the proposed design model. This study presents an important step for fire resistance calculations of timber frame assemblies.

The purpose of this paper is to introduce the simple synthesis process of thermal-insulation coating by using three different nanoparticles, namely, nano-zinc oxide (ZnO), nano-tin dioxide (SnO₂) and nano-titanium dioxide (TiO₂), which can reduce the temperature of solar cells.

The thermal-insulation coating is designed using sol-gel process. The aminopropyltriethoxysilane/methyltrimethoxysilane binder system improves the cross-linking between the hydroxyl groups, -OH of nanoparticles. The isopropyl alcohol is used as a solvent medium. The fabrication method is a dip-coating method.

The prepared S1B1 coating (20 Wt.% of SnO₂) exhibits high transparency and great thermal insulation property where the surface temperature of solar cells has been reduced by 13°C under 1,000 W/m² irradiation after 1 h. Meanwhile, the Z1B2 coating (20 Wt.% of ZnO) reduced the temperature of solar cells by 7°C. On the other hand, the embedded nanoparticles have improved the fill factor of solar cells by 0.2 or 33.33%.

Findings provide a significant method for the development of thermal-insulation coating by a simple synthesis process and low-cost materials.

The thermal-insulation coating is proposed to prevent exterior heat energy to the inside solar panel glass. At the same time, it can prevent excessive heating on the solar cell’s surface, later improves the efficiency of solar cell.

This study presents a the novel method to develop and compare the thermal-insulation coating by using various nanoparticles, namely, nano-TiO₂, nano-SnO₂ and nano-ZnO at different weight percentage.

The sustainable performance of hotels which constitute a major part of the tourism industry, gains increasing importance day by day. Sustainability has become mandatory not only for the tourism industry but also for all industries producing goods and services. Reducing the negative impact of development on the environment and environmental innovation which aims to benefit from natural resources and energy effectively and consciously helps hotels to be sustainable. The tourism industry has a complex structure and exists as being intertwined with other branches of science. Tourism, which is a multidisciplinary industry, is nourished by other branches of science as well as supplies other fields of science by providing working space. Some new solutions that are put forward by materials science and engineering take place in the tourism industry as new innovations. Owing to this interaction, the workload of the personnel working in hotels is reduced and the enterprises save material and energy. At the same time, the customers who benefit from the services of the hotels consume the services in more comfortable and safer environments.

Ceramic materials are generally used in toilet and bathroom parts of hotels. However, ceramics are observed to be used in lobbies, cafes, restaurants, pools, facades, and similar areas in addition to toilets and baths in hotels. The aim of this study is to identify new ceramic solutions that affect and contribute to the sustainability of the hotels which is a major sector under the roof of the tourism industry and to contribute the literature. In order to actualize this aim, the document analysis method which is one of qualitative research methods was used and the literature search was carried out to identify new ceramic solutions. The result of study includes moisture control tiles with the ability to keep the humidity at normal standards in terms of human health and that can be used in hotels, facade systems that clean themselves and the polluted air, thermal coating systems for heat insulation, antibacterial materials that provide hygiene, and dirt repelling products. Also, it is seen that there are new ceramic solutions such as costless night lighting and security strips as well as materials with a phosphorescence property for aesthetical purposes and also, tiles with heat control which offer different possibilities aesthetically. It is observed that the different benefits obtained from each of identified new ceramic solutions ease off the workload of personnel working in the hotels, enable material and energy saving in hotels and at the same time, provide an accommodation in a more comfortable and safer environment for customers. In addition to this, the use of high-technology ceramics and nanomaterials in the field of tourism creates places where technology and aesthetics combine.

The present study provides a comprehensive review of the advancements in five active heating modes for cold-proof clothing as of 2021. It aims to evaluate the current state of research for each heating mode and identify their limitations. Further, the study provides insights into the optimization of intelligent temperature control algorithms and design considerations for intelligent cold-proof clothing.

This article presents a classification of active heating systems based on five different heating principles: electric heating system, solar heating system, phase-change material (PCM) heating system, chemical heating system and fluid/air heating system. The systems are analyzed and evaluated in terms of heating principle, research advancement, scientific challenges and application potential in the field of cold-proof clothing.

The rational utilization of active heating modes enhances the thermal efficiency of cold-proof clothing, resulting in enhanced cold-resistance and reduced volume and weight. Despite progress in the development of the five prevalent heating modes, particularly with regard to the improvement and advancement of heating materials, the current integration of heating systems with cold-proof clothing is limited to the torso and limbs, lacking consideration of the thermal physiological requirements of the human body. Additionally, the heating modes of each system tend to be uniform and lack differentiation to meet the varying cold protection needs of various body parts.

The effective application of multiple heating modes helps the human body to maintain a constant body temperature and thermal equilibrium in a cold environment. The research of heating mode is the basis for realizing the temperature control of cold-proof clothing and provides an effective guarantee for the future development of the intelligent algorithms for temperature control of non-uniform heating of body segments.

The integration of multiple heating modes ensures the maintenance of a constant body temperature and thermal balance for the wearer in cold environments. The research of heating modes forms the foundation for the temperature regulation of cold-proof clothing and lays the groundwork for the development of intelligent algorithms for non-uniform heating control of different body segments.

The present article systematically reviews five active heating modes suitable for use in cold-proof clothing and offers guidance for the selection of heating systems in future smart cold-proof clothing. Furthermore, the findings of this research provide a basis for future research on non-uniform heating modes that are aligned with the thermal physiological needs of the human body, thus contributing to the development of cold-proof clothing that is better suited to meet the thermal needs of the human body.

The purpose of this paper is to determine thermal behaviour of wing fuel tank wall via heating by external heat sources.

A 3D finite element model of the structure has been created that takes into account convection, conduction and radiation effects. In addition, a 3D finite volume model of the air inside the leading edge is created. Through a computational fluid dynamics approach, the flow of air and thermal behaviour of the air is modelled. The structure and fluid model are coupled via a co-simulation engine to exchange heat flux and temperature. Different ventilation cases of the leading edge and their impact on the thermal behaviour of the tank wall (corresponding to the front spar) are investigated.

Results of 3D analysis illustrate good insight into the thermal behaviour of the tank wall. Furthermore, if regions exist in the leading edge that differs significantly from the overall thermal picture of the leading edge, these are visible in a 3D analysis. Finally, the models can be used to support a flammability analysis assessment.

Provided that the bleed pipe is located far enough from the spar and covered with sufficient thermal heat isolation, the composite leading edge structure will not reach extremely high temperatures.

These detailed simulations provide accurate results which can be used as reliable input for the fuel tank flammability analysis.

This paper aims to develop a numerical model to investigate coupled conduction radiation heat transfer in a multilayer semi-transparent polymeric foam.

The model uses a multi-phase approach in which the radiative transfer is determined by solving the radiative transfer equation explicitly in the whole medium incorporating an interface condition valid in the geometric optics rgime. This is executed by using a combination of ray splitting and a discrete curved ray tracing technique. Both partial photon reflection and total internal reflection at the interface are considered in the present investigation.

The directional distribution of intensity within the whole medium can be determined, which is used to obtain the detailed temperature profile inside the domain. The performance of the proposed methodology has been tested by simulating the modelled foam at ambient conditions. The results obtained from the simulations are in good agreement with the published results and shows that there is a global non-linearity in the temperature profile in problems where conduction to radiation parameter is small.

Specular nature of radiative transfer at the interface is accounted for in the present analysis. Instead of working with direction integrated quantities (as in the case of P1 approximation), each bundle of rays is treated separately within the whole medium. This model serves as a starting point for a detailed spatially three dimensional study of heat transfer in foams and the mathematical nature of the formulation is such that it may result in an implementation to three-dimensions.

The rest-to-rest movements for a spacecraft, such as attitude adjustment and orbital manoeuver, are likely to excite residual vibration of flexible appendages, which may affect the attitude accuracy and even result in severe structural damage. The purpose of this paper is to present an approach to attenuating the vibration of flexible solar array by using reaction flywheel.

The reaction flywheel installed on solar array served as an actuator to provide reaction torque to a structure according to a designed feedback control law. This torque can be considered as an artificial damping. Experiment on a scale model of the solar array is first performed to verify the effectiveness of this method. Numerical simulation on finite element model of a full-scale solar array is subsequently carried out to confirm the validity of this method for practical engineering application.

The vibration suppression effect on the structure using a reaction flywheel is deduced by theoretical analysis. Results from both experiment and numerical simulation reveal that the efficiency of vibration attenuation is promoted.

Improvements on control law are left for further study. Additionally, only the first-order bending vibration of the flexible solar array is attenuated, and further study is required for other types of vibration suppression.

An effective method is proposed for spacecraft designers to actively suppress the vibration of the flexible solar array.

A novel active vibration reduction scheme is proposed using a reaction flywheel to suppress vibration of the flexible solar array. This paper fulfils a source of theoretical analysis and experimental studies for vibration reduction measure design and provides practical help for the spacecraft designers.

The purpose of this paper is to propose and assess the possibility of using ceramic coating layer as a heat‐resistant material in micro solid propellant thruster.

A ceramic layer is coated on the inner surface of the combustor of a micro thruster by applying micro‐arc oxidation (MAO) technology. The thermal property of the coating is analyzed with laser pulse method. To evaluate the heat‐resistant performance of the coating, the temperature history of the micro thruster inner surface is experimentally tested and recorded in a water thermostat bath. A numerical simulation of the thruster working condition is also carried out.

Both experimental and simulation results reveal that the heat‐resistant ability of the coating processed by MAO is proven to be effective.

This paper attempts to help designers choose material processing technology to improve micro solid propellant thruster heat‐resistant ability.

The paper shows that with a ceramic coating layer processed with MAO, aluminium can sustain higher temperature and it can be used as the structural material for short‐time‐work micro thruster.