The thermal protection materials and structures are widely used in hypersonic vehicles for the purpose of thermal insulation, and their mechanical behavior is one of the key issues in design and manufacture of hyperso...The thermal protection materials and structures are widely used in hypersonic vehicles for the purpose of thermal insulation, and their mechanical behavior is one of the key issues in design and manufacture of hypersonic vehicles. It is our great pleasure to present the seven papers in this special subject of Theoretical & Applied Mechanics Letters (TAML) and introduce the recent progresses on the mechanical behavior of thermal protection materials and structures by the authors.展开更多
In offshore structures,hydrocarbon fires cause the structure to loose its rigidity rapidly and this leads to structural integrity and stability problems.The Passive Fire Protection(PFP)system slows the transfer rate o...In offshore structures,hydrocarbon fires cause the structure to loose its rigidity rapidly and this leads to structural integrity and stability problems.The Passive Fire Protection(PFP)system slows the transfer rate of fire heat and helps to prevent the collapse of structures and human losses.The vital design factors are decided in the detailed design stage.The determined design thickness must be accurately applied in the fabrication yard.However,there are many cases that the PFP is overused because of various reasons.This excessive application of the PFP is an unavoidable problem.Several studies have been conducted on the efficient application and optimal design of the PFP.However,the strength of the PFP has not been considered.In addition,research studies on the correlation between the thickness of the PFP and the structural behaviour are not widely available.Therefore,this study attempts to analyse the thermal and mechanical effects of the PFP on the structure when it is applied to the structural member.In particular,it is intended to determine the change in the behaviour of the structural member as the thickness of the PFP increases.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
Solar energy has always been a kind of energy with large reserves and wide application.It is well utilized through solar absorbers.In our study,the finite difference time domain method(FDTD)is used to simulate the abs...Solar energy has always been a kind of energy with large reserves and wide application.It is well utilized through solar absorbers.In our study,the finite difference time domain method(FDTD)is used to simulate the absorber composed of refractory metal materials,and its absorption performance and thermal emission performance are obtained.The ultra-wide band of 200 nm-3000 nm reaches 95.93%absorption efficiency,of which the bandwidth absorption efficiency of2533 nm(200 nm-2733 nm)is greater than 90%.The absorption efficiency in the whole spectrum range(200 nm-2733 nm)is 97.17%on average.The multilayer nanodisk structure of the absorber allows it to undergo strong surface plasmon resonance and near-field coupling when irradiated by incident light.The thermal emission performance of the absorber enables it to also be applied to the thermal emitter.The thermal emission efficiency of 95.37%can be achieved at a high temperature of up to 1500 K.Moreover,the changes of polarization and incident angle do not cause significant changes in absorption.Under the gradual change of polarization angle(0°-90°),the absorption spectrum maintains a high degree of consistency.As the incident angle increases from 0°to 60°,there is still 85%absorption efficiency.The high absorption efficiency and excellent thermal radiation intensity of ultra-wideband enable it to be deeply used in energy absorption and conversion applications.展开更多
A theoretical analysis is presented to predict the nonlinear thermo-structural response of metallicsandwich panels with truss cores under through-thickness gradient temperature field, which is acommon service condit...A theoretical analysis is presented to predict the nonlinear thermo-structural response of metallicsandwich panels with truss cores under through-thickness gradient temperature field, which is acommon service condition for metallic thermal protection system (TPS). The in-planetemperature distribution is assumed to be uniform, and through-thickness temperature field isdetermined by heat conduction. Two typical conditions are analyzed: nonlinear thermal bendingin fixed inside surface temperature, and thermal post-buckling in fixed temperature differencebetween two surfaces. Temperature-dependent mechanical properties are considered, andgradient shear stiffness and bending stiffness due to non-uniform temperature is included. Resultsindicate that the temperature-dependent material properties obviously affect bending resistance;however, the effect is negligible on post-buckling behavior. Influences of geometric parameters onthe thermo-structural behavior of the sandwich panel according to the present theoretical modelare discussed.展开更多
基金support from the Natural Science Foundation of China(91016029,91216302,and 91216301)
文摘The thermal protection materials and structures are widely used in hypersonic vehicles for the purpose of thermal insulation, and their mechanical behavior is one of the key issues in design and manufacture of hypersonic vehicles. It is our great pleasure to present the seven papers in this special subject of Theoretical & Applied Mechanics Letters (TAML) and introduce the recent progresses on the mechanical behavior of thermal protection materials and structures by the authors.
基金This research is supported by PNU Korea-UK Global Program in Offshore Engineering(N0001288)funded by the Ministry of Trade,Industry and Energy.
文摘In offshore structures,hydrocarbon fires cause the structure to loose its rigidity rapidly and this leads to structural integrity and stability problems.The Passive Fire Protection(PFP)system slows the transfer rate of fire heat and helps to prevent the collapse of structures and human losses.The vital design factors are decided in the detailed design stage.The determined design thickness must be accurately applied in the fabrication yard.However,there are many cases that the PFP is overused because of various reasons.This excessive application of the PFP is an unavoidable problem.Several studies have been conducted on the efficient application and optimal design of the PFP.However,the strength of the PFP has not been considered.In addition,research studies on the correlation between the thickness of the PFP and the structural behaviour are not widely available.Therefore,this study attempts to analyse the thermal and mechanical effects of the PFP on the structure when it is applied to the structural member.In particular,it is intended to determine the change in the behaviour of the structural member as the thickness of the PFP increases.
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support from the National Natural Science Foundation of China (Grant No.51606158,11604311,12074151)the Guangxi Science and Technology Base and Talent Special Project (Grant No.AD21075009)+6 种基金the Sichuan Science and Technology Program (Grant No.2021JDRC0022)the Natural Science Foundation of Fujian Province (Grant No.2021J05202)the Research Project of Fashu Foundation (Grant No.MFK23006)the Open Fund of the Key Laboratory for Metallurgical Equipment and Control Technology of Ministry of Education in Wuhan University of Science and Technology,China (Grant No.MECOF2022B01MECOF2023B04)the Project supported by Guangxi Key Laboratory of Precision Navigation Technology and Application,Guilin University of Electronic Technology (Grant No.DH202321)the Scientific Research Project of Huzhou College (Grant No.2022HXKM07)。
文摘Solar energy has always been a kind of energy with large reserves and wide application.It is well utilized through solar absorbers.In our study,the finite difference time domain method(FDTD)is used to simulate the absorber composed of refractory metal materials,and its absorption performance and thermal emission performance are obtained.The ultra-wide band of 200 nm-3000 nm reaches 95.93%absorption efficiency,of which the bandwidth absorption efficiency of2533 nm(200 nm-2733 nm)is greater than 90%.The absorption efficiency in the whole spectrum range(200 nm-2733 nm)is 97.17%on average.The multilayer nanodisk structure of the absorber allows it to undergo strong surface plasmon resonance and near-field coupling when irradiated by incident light.The thermal emission performance of the absorber enables it to also be applied to the thermal emitter.The thermal emission efficiency of 95.37%can be achieved at a high temperature of up to 1500 K.Moreover,the changes of polarization and incident angle do not cause significant changes in absorption.Under the gradual change of polarization angle(0°-90°),the absorption spectrum maintains a high degree of consistency.As the incident angle increases from 0°to 60°,there is still 85%absorption efficiency.The high absorption efficiency and excellent thermal radiation intensity of ultra-wideband enable it to be deeply used in energy absorption and conversion applications.
基金The financial support from the National Natural Science Foundation of China (91016025, 11472276, 11602271, and 11332011)the Defense Industrial Technology Development Program of China (JCKY2016130B009)
文摘A theoretical analysis is presented to predict the nonlinear thermo-structural response of metallicsandwich panels with truss cores under through-thickness gradient temperature field, which is acommon service condition for metallic thermal protection system (TPS). The in-planetemperature distribution is assumed to be uniform, and through-thickness temperature field isdetermined by heat conduction. Two typical conditions are analyzed: nonlinear thermal bendingin fixed inside surface temperature, and thermal post-buckling in fixed temperature differencebetween two surfaces. Temperature-dependent mechanical properties are considered, andgradient shear stiffness and bending stiffness due to non-uniform temperature is included. Resultsindicate that the temperature-dependent material properties obviously affect bending resistance;however, the effect is negligible on post-buckling behavior. Influences of geometric parameters onthe thermo-structural behavior of the sandwich panel according to the present theoretical modelare discussed.