The bench top test is one of the most important and effective methods to evaluate the total thermal protective performance(TPP) of firefighters' protective clothing,which is greatly influenced by the air gaps entr...The bench top test is one of the most important and effective methods to evaluate the total thermal protective performance(TPP) of firefighters' protective clothing,which is greatly influenced by the air gaps entrapped.In this paper,to investigate the effect of air gap width on TPP,a new improved apparatus with two height changeable buttons to hold the thermal sensor was developed to get a series of air gap sizes from 0 mm to 40 mm.The TPP of two types of flame-resistant outer fabrics was measured with TPP test apparatus respectively.Analysis of temperature rise with each air gap width was made to determine the effects of different air gaps on protective performance.It was indicated that air gap size had great effect on TPP of fabrics in the bench top test.An air gap width above 8 mm was suggested for the thermal protective clothing design.展开更多
Cotton fabrics treated with phase change materials( PCMs)were used in multi-layered fabrics of the fire fighter protective clothing to study its effect on thermal protection. The thermal protective performance( TPP) o...Cotton fabrics treated with phase change materials( PCMs)were used in multi-layered fabrics of the fire fighter protective clothing to study its effect on thermal protection. The thermal protective performance( TPP) of the multi-layered fabrics was measured by a TPP tester under flash fire. Results showed that the utilization of the PCM fabrics improved the thermal protective performance of the multi-layered fabrics. The fabric with a PCM add on of 41. 9% increased the thermal protection by 50. 6% and reduced the time to reach a second degree burn by 8. 4 s compared with the reference fabrics( without PCMs). The employment of the PCM fabrics also reduced the blackened areas on the inner layers. The PCM fabrics with higher PCM melting temperature could bring higher thermal protective performance.展开更多
High-entropy rare-earth aluminate(Y_(0.2)Yb_(0.2)Lu_(0.2)Eu_(0.2)Er_(0.2))_(3)Al_(5)O_(12)(HE-RE_(3)Al_(5)O_(12))has been considered as a promising thermal protection coating(TPC)material based on its low thermal cond...High-entropy rare-earth aluminate(Y_(0.2)Yb_(0.2)Lu_(0.2)Eu_(0.2)Er_(0.2))_(3)Al_(5)O_(12)(HE-RE_(3)Al_(5)O_(12))has been considered as a promising thermal protection coating(TPC)material based on its low thermal conductivity and close thermal expansion coefficient to that of Al2O3.However,such a coating has not been experimentally prepared,and its thermal protection performance has not been evaluated.To prove the feasibility of utilizing HE-RE_(3)Al_(5)O_(12) as a TPC,HE-RE_(3)Al_(5)O_(12) coating was deposited on a nickelbased superalloy for the first time using the atmospheric plasma spraying technique.The stability,surface,and cross-sectional morphologies,as well as the fracture surface of the HE-RE_(3)Al_(5)O_(12) coating were investigated,and the thermal shock resistance was evaluated using the oxyacetylene flame test.The results show that the HE-RE_(3)Al_(5)O_(12) coating can remain intact after 50 cycles at 1200℃ for 200 s,while the edge peeling phenomenon occurs after 10 cycles at 1400℃ for 200 s.This study clearly demonstrates that HE-RE_(3)Al_(5)O_(12) coating is effective for protecting the nickel-based superalloy,and the atmospheric plasma spraying is a suitable method for preparing this kind of coatings.展开更多
基金National Natural Science Foundation of China (No. 50876019)the Research Fund for the Doctoral Program of Higher Education of China (No. 200802550009)Fundamental Research Funds for the Central Universities,China
文摘The bench top test is one of the most important and effective methods to evaluate the total thermal protective performance(TPP) of firefighters' protective clothing,which is greatly influenced by the air gaps entrapped.In this paper,to investigate the effect of air gap width on TPP,a new improved apparatus with two height changeable buttons to hold the thermal sensor was developed to get a series of air gap sizes from 0 mm to 40 mm.The TPP of two types of flame-resistant outer fabrics was measured with TPP test apparatus respectively.Analysis of temperature rise with each air gap width was made to determine the effects of different air gaps on protective performance.It was indicated that air gap size had great effect on TPP of fabrics in the bench top test.An air gap width above 8 mm was suggested for the thermal protective clothing design.
基金Fundamental Research Funds for the Central Universities,China(No.14D110715/17/18)Start up Fund by Shanghai University of Engineering Science(No.2015-69)Young Teacher Training Program by Shanghai,China(No.ZZGCD15051))
文摘Cotton fabrics treated with phase change materials( PCMs)were used in multi-layered fabrics of the fire fighter protective clothing to study its effect on thermal protection. The thermal protective performance( TPP) of the multi-layered fabrics was measured by a TPP tester under flash fire. Results showed that the utilization of the PCM fabrics improved the thermal protective performance of the multi-layered fabrics. The fabric with a PCM add on of 41. 9% increased the thermal protection by 50. 6% and reduced the time to reach a second degree burn by 8. 4 s compared with the reference fabrics( without PCMs). The employment of the PCM fabrics also reduced the blackened areas on the inner layers. The PCM fabrics with higher PCM melting temperature could bring higher thermal protective performance.
基金the National Key Laboratory Foundation of Science and Technology on Materials under Shock and Impact(No.6142902200202)the National Natural Science Foundation of China(No.52002355)+1 种基金the Outstanding Youth Foundation of Henan Province(No.202300410355)Young Talent Lifting Project of the China Association for Science and Technology(No.YESS20200241).
文摘High-entropy rare-earth aluminate(Y_(0.2)Yb_(0.2)Lu_(0.2)Eu_(0.2)Er_(0.2))_(3)Al_(5)O_(12)(HE-RE_(3)Al_(5)O_(12))has been considered as a promising thermal protection coating(TPC)material based on its low thermal conductivity and close thermal expansion coefficient to that of Al2O3.However,such a coating has not been experimentally prepared,and its thermal protection performance has not been evaluated.To prove the feasibility of utilizing HE-RE_(3)Al_(5)O_(12) as a TPC,HE-RE_(3)Al_(5)O_(12) coating was deposited on a nickelbased superalloy for the first time using the atmospheric plasma spraying technique.The stability,surface,and cross-sectional morphologies,as well as the fracture surface of the HE-RE_(3)Al_(5)O_(12) coating were investigated,and the thermal shock resistance was evaluated using the oxyacetylene flame test.The results show that the HE-RE_(3)Al_(5)O_(12) coating can remain intact after 50 cycles at 1200℃ for 200 s,while the edge peeling phenomenon occurs after 10 cycles at 1400℃ for 200 s.This study clearly demonstrates that HE-RE_(3)Al_(5)O_(12) coating is effective for protecting the nickel-based superalloy,and the atmospheric plasma spraying is a suitable method for preparing this kind of coatings.
