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1 – 10 of over 5000Zhongxiang Lei, Xiaoming Qian and Xianglong Zhang
The purpose of this paper is to assess the thermal protective performance of firefighter’s clothing by a sweating manikin in low-level radiation.
Abstract
Purpose
The purpose of this paper is to assess the thermal protective performance of firefighter’s clothing by a sweating manikin in low-level radiation.
Design/methodology/approach
A new method and a novel objective index based on measurements of the sweating thermal manikin are proposed to measure the thermal protection performance of firefighter’s clothing under low-level radiation exposure of 3.0 kW/m2. Finally, the effect of thermal insulation on thermal protective performance of firefighter’s clothing was analyzed.
Findings
The results reveal that the new index which used the changing rate of core temperature of the clothed manikin is a vital indicator of the thermal protection performance. Furthermore, the results demonstrated that there is a linear correlation between thermal protection performance of firefighter’s clothing and the thermal insulation.
Originality/value
A new method and a novel objective index are proposed to quantify the thermal protective performance of firefighter’s clothing in low-level radiation.
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Qingmao Zhang and Guansheng Li
This study reviews the application of the C/SiC composites in the thermal protection systems (TPS). Special attention is put on the structure design and optimization of the C/SiC…
Abstract
This study reviews the application of the C/SiC composites in the thermal protection systems (TPS). Special attention is put on the structure design and optimization of the C/SiC shell panel. The comparisons of several TPS show that the ceramic matrix composite (CMC) is one of the most potential materials for TPS. The crucial role of multi‐disciplinary design and optimization is pointed out in the future design of C/SiC thermal protection structure. This review provides a guideline on the current and future study of C/SiC thermal protection structure.
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Akram Hassan Mohammed Ali and Weidong Yu
The purpose of this paper is to investigate thermal protection provided by the fire fighting fabric systems with different layer under high-level thermal hazards with a typical…
Abstract
Purpose
The purpose of this paper is to investigate thermal protection provided by the fire fighting fabric systems with different layer under high-level thermal hazards with a typical temperature range of 800-1,000°C. The purpose of these fabric systems was to provide actual protection against burn injuries using garments worn by industrial workers, fire fighters and military personnel, etc.
Design/methodology/approach
The fabric system was consist of glass with aluminum foil as an outer layer, non-woven basalt, non-woven glass fabric containing NaCl-MgCl2 and Galactitol phase change materials (PCM) which simulate multilayer fire fighter protective clothing system. Thermal protective performance tests were applied for thermal analysis and used as an attempt to quantify the insulating characteristics of fabrics under conditions of flash over temperature. The surface of fire fighting multilayer protective fabric has been characterized using the UV-Vis-NIR (ultraviolet-visible-near infrared) spectrophotometer
Findings
The clothing shows good thermal insulation and high-temperature drop during flash over environment and avoid second degree burn. The current PCM obvious advantages such as the ability to work in high temperature, high efficiency a long period of practical performance.
Originality/value
Using this design of composite multilayer technology incorporating two stages of PCM may provide people with better protection against the fire exposure and increasing the duration time which was estimated to be more than five minutes to prevent burn injuries.
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Yun Su, Yunyi Wang and Jun Li
The purpose of this paper is to provide the details of developments to researchers in test apparatus and evaluation methods to rate the thermal protective performance (TPP) of…
Abstract
Purpose
The purpose of this paper is to provide the details of developments to researchers in test apparatus and evaluation methods to rate the thermal protective performance (TPP) of firefighters’ clothing under high-temperature and high-humidity condition.
Design/methodology/approach
This review paper describes the influence laws of moisture on thermal protection and the moisture distribution in actual fire environment. Different evaluation methods used for assessing the effect of moisture on the TPP were investigated, with an emphasis on test devices, evaluation indexes as well as their relationship and limitations.
Findings
The moisture from the ambient, clothing and human perspiration plays an important role in determining the TPP of firefighter protective clothing. It is obvious that research on moisture-driven heat transfer in firefighter’s clothing system are comparatively little, primarily focussing on pre-wetted methods of multi-layer fabric. Further studies should be conducted to develop more standardized moistening systems and improve the current calculation methods for evaluating the performance of protective clothing. New explorations for heat and moisture transfer mechanism in protective clothing should be investigated.
Practical implications
Protective clothing is the efficient way to provide fire-fighting occupational safety. To accurately evaluate the TPP of protective clothing under high-temperature and high-humidity condition will help to optimize the clothing performance and choose the proper clothing for providing firefighters with the best protection under multiple thermal hazards.
Originality/value
This paper is offered as a concise reference for scientific community further research in the area of the TPP evaluation methods under high-temperature and high-humidity condition.
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Pelin Altay, Selin Hanife Eryürük, Gülay Özcan, Didem Öztürk, Melda Naz Saral and Çağla Altınordu
Firefighters are exposed to high outdoor temperature and heat stress caused by metabolic activities during firefighting and should wear protective clothing to ensure their safety…
Abstract
Purpose
Firefighters are exposed to high outdoor temperature and heat stress caused by metabolic activities during firefighting and should wear protective clothing to ensure their safety and health. Traditional firefighter protective suits are bulky and heavy garments with reduced thermal comfort properties since the fabric thickness and moisture barrier layers prevent heat transfer of the garment and cause additional heat stress. The aim of this study is to reduce heat stress by creating a new fabric design with silica aerogel membrane as a moisture barrier for three-layer fabric system.
Design/methodology/approach
Polyacrylonitrile (PAN) nanofibers were produced with three different silica aerogel contents and used for three-layered clothing system as a moisture barrier for giving desired protectiveness and thermal comfort to firefighters. Different fabric combinations were designed using two types of outer shell fabrics, two types of moisture barrier fabrics, two types of thermal barrier fabrics and PAN/silica aerogel membranes.
Findings
The results show that a lighter fabric system with improved wearer’s mobility and thermal comfort properties (thermal resistance and moisture permeability) is achieved with the use of PAN/silica aerogel membrane as an intermediate layer compared to commercial thermal protective fabric systems.
Originality/value
Differently from traditional thermal protective clothing, which may not provide adequate protection in long-term heat conditions or when exposed to flash fire, a new thermal protective clothing has been developed to be used in extremely hot environments, providing desired technical and performance properties, ease to wear comfort.
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Examines the sixteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects…
Abstract
Examines the sixteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.
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Abstract
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In this paper, a simple original method and instrument for testing the thermal efficiency of garments containing PCM particles is described. The efficiency is characterized by the…
Abstract
In this paper, a simple original method and instrument for testing the thermal efficiency of garments containing PCM particles is described. The efficiency is characterized by the length of time that the garment can offer protection, when the effective thermal resistance is at least two times higher then the thermal resistance of the same garment without any PCM function. The related instrument can simulate any boundary conditions typical for the wearing of PCM garments. The good functionality of the instrument was verified by the tests. The experiments revealed that the length of time that the tested commercial garments could offer protection is quite short.
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The main purpose of this study, reflecting mainly the content of the authors’ plenary lecture, is to make a brief overview of several approaches developed by the author and his…
Abstract
Purpose
The main purpose of this study, reflecting mainly the content of the authors’ plenary lecture, is to make a brief overview of several approaches developed by the author and his colleagues to the solution to ill-posed inverse heat transfer problems (IHTPs) with their possible extension to a wider class of inverse problems of mathematical physics and, most importantly, to show the wide possibilities of this methodology by examples of aerospace applications. In this regard, this study can be seen as a continuation of those applications that were discussed in the lecture.
Design/methodology/approach
The application of the inverse method was pre-tested with experimental investigations on a special test equipment in laboratory conditions. In these studies, the author used the solution to the nonlinear inverse problem in the conjugate (conductive and convective) statement. The corresponding iterative algorithm has been developed and tested by a numerical and experimental way.
Findings
It can be stated that the theory and methodology of solving IHTPs combined with experimental simulation of thermal conditions is an effective tool for various fundamental and applied research and development in the field of heat and mass transfer.
Originality/value
With the help of the developed methods of inverse problems, the investigation was conducted for a porous cooling with a gaseous coolant for heat protection of the re-entry vehicle in the natural environment of hypersonic flight. Moreover, the analysis showed that the inverse methods can make a useful contribution to the study of heat transfer at the surface of a solid body under the influence of the hypersonic heterogeneous (dusty) gas stream and in many other aerospace applications.
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Paper aims to present problem of aerodynamic heating of a metallic heat shield. The key elements of this construction are metallic layers of superalloy honeycomb, which…
Abstract
Purpose
Paper aims to present problem of aerodynamic heating of a metallic heat shield. The key elements of this construction are metallic layers of superalloy honeycomb, which significantly increase the structure’s resistance to impact. Paper describes the problem of influence of damage size on increase of thermal load.
Design/methodology/approach
Numerical analysis was performed in a non-commercial environment FreeFem++ using finite element method, and its results were compared with the results given in the literature.
Findings
In thermal protection system, a modification was used to delay increase in temperature on the underlying structure as well as to reduce its maximum value.
Originality/value
In the further part of the paper, selected insulation material was modified by adding additional conductive material.
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