The Experts below are selected from a list of 12 Experts worldwide ranked by ideXlab platform
Gagnon, Brian D. - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of New Test Methods for Fire Fighting Clothing
Digital WPI, 2000Co-Authors: Gagnon, Brian D.Abstract:Despite advancements in the development of synthetic fibers and materials that provide better insulation, fire ground burn injuries remain a significant issue. The current test methods for fire fighting clothing were investigated to determine their adequacy in evaluating the actual performance of clothing materials. This investigation uncovered several potential problems with the current test methods. A series of new, small scale, tests were used to evaluate the shortcomings of the current test methods and develop possible improvements. A small test apparatus, designed and donated by Ktech Corporation, was used to measure the thermal properties (thermal conductivity and volumetric heat capacity) of a series of fire fighting clothing materials. The thermal properties were estimated for single fabric layers, as well as ensembles, with various levels of moisture added to simulate actual end use conditions. In addition, a Skin Simulant Sensor was used to assess the time to 2nd degree burn for exposures similar to those required in current standards for fire fighting clothing. A one dimensional heat conduction model was developed to predict the time to 2nd degree burn for the Skin Simulant Sensor protected with outer shell materials that may be used as wildland fire fighting clothing, using the thermal property data obtained from earlier tests. An alternative method was developed to calculate the time to 2nd degree burn for ensembles evaluated with the new Skin Simulant Sensor. The predictions for the time to 2nd degree burn obtained from the new Skin Simulant Sensor were compared against results obtained using the Sensor specified in the current test methods. The predictions for the Skin Simulant Sensor were consistently shorter than those from the current test Sensor. The current test Sensor predictions for the time to 2nd degree burn were nominally 40% to 50% higher than the predictions from the Skin Simulant Sensor during the evaluations of outer shell materials
Miao Tia - One of the best experts on this subject based on the ideXlab platform.
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simulating the thermal response of the flame manikin with different materials exposed to flash fire by cfd
Fire and Materials, 2017Co-Authors: Miao TiaAbstract:Summary To investigate the differences of thermal response between heat flux Sensors and human Skin on the flame manikin, a three-dimensional heat transfer model was developed and validated by the flame manikin system. The initial temperature of the model with Sensor material was set to 300 K, and the model with Skin material was set as the real condition. Simulated results validated the effectiveness of heat flux measured by the Sensor. The incident heat flux through the measured surface was influenced by the different emissivity of the human Skin and experimental Sensors. Significant difference was found for the temperature response of these two kinds of materials within 4-s fire exposure. The heat flux measured by Sensor or the simulated results with actual human Skin parameters could be used as the input boundary condition of the Skin heat transfer model for Henriques's Skin burn prediction. It is necessary to study the actual Skin thermal response by experiments, where the 3D model established in this study could be used as the supplementary means for Skin Simulant Sensor development. These findings will also be adopted in our following study of Skin burn prediction module in the 3D full-scale simulation platform. Copyright © 2016 John Wiley & Sons, Ltd.
Wei-yuan Zhang - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of Thermal Performance of Flame-resistant Fabrics Considering Thermal Wave Influence in Human Skin Model
Journal of Fire Sciences, 2006Co-Authors: Fang-long Zhu, Wei-yuan ZhangAbstract:A thermal wave Skin model incorporating surface heat flux from a Skin Simulant Sensor is developed to characterize the thermal performance of flame-resistant (FR) fabrics covering the Skin Simulant Sensor. Comparison of the results of time to 2nd degree Skin burn and temperature elevation of Skin beneath a layer of fabric obtained from the newly developed thermal wave Skin model to the results obtained by using the Pennes' equation is performed in this research. Results of tolerance time from Stoll criterion method are also compared with Henriques burn damage integral from two Skin models between constant-flux exposures in TPP calorimeter. Investigations have been conducted to find the effects of structural parameter, air pressure, and air layer thickness on the thermal performance of the selected FR fabric determined by the newly developed Skin model and the method. It is concluded that the thermal protective performance of FR fabrics can be characterized here more precisely than in previous work.
N R Keltner - One of the best experts on this subject based on the ideXlab platform.
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evaluating thermal protective performance testing
Journal of Astm International, 2005Co-Authors: N R KeltnerAbstract:Even as better materials are developed for protective clothing, NFPA data indicate the number of burn related fire fighter deaths and severe injuries is increasing. These injuries are unexpected for the most part. As a result, questions arise about Thermal Protective Performance (TPP) ratings and whether performance changes are due to use or the effects of aging. As part of a NIST-sponsored Small Business Innovative Research project, current TPP test techniques were evaluated. Some changes and extensions are suggested. In TPP tests, dry fabric samples or ensembles are exposed to heat flux of 83 kW/m2 with nominally 50% radiative and 50% convective heat transfer. Heat transmission through the test sample is measured with a copper calorimeter. The TPP Rating is the time in seconds required for a 2nd degree burn. Current problems include: 1) Current test methods overestimate time to 2nd degree burn. 2) No information is provided on maximum potential burn damage. 3) No information is provided on heat transfer or fabric properties. 4) No information is provided on how performance changes with use. Suggested changes and extensions include: 1) Change the heat source — use a modified radiant protective performance technique. 2) Replace the copper calorimeter with a thermal Skin Simulant Sensor. 3) Estimate burn damage using a two step analysis method. 4) Obtain both dry and damp thermal properties for modeling clothing performance.
Fang-long Zhu - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of Thermal Performance of Flame-resistant Fabrics Considering Thermal Wave Influence in Human Skin Model
Journal of Fire Sciences, 2006Co-Authors: Fang-long Zhu, Wei-yuan ZhangAbstract:A thermal wave Skin model incorporating surface heat flux from a Skin Simulant Sensor is developed to characterize the thermal performance of flame-resistant (FR) fabrics covering the Skin Simulant Sensor. Comparison of the results of time to 2nd degree Skin burn and temperature elevation of Skin beneath a layer of fabric obtained from the newly developed thermal wave Skin model to the results obtained by using the Pennes' equation is performed in this research. Results of tolerance time from Stoll criterion method are also compared with Henriques burn damage integral from two Skin models between constant-flux exposures in TPP calorimeter. Investigations have been conducted to find the effects of structural parameter, air pressure, and air layer thickness on the thermal performance of the selected FR fabric determined by the newly developed Skin model and the method. It is concluded that the thermal protective performance of FR fabrics can be characterized here more precisely than in previous work.