The novel calcium-silicate-hydrate(C-S-H)/paraffin composite phase change materials were synthesized using a discontinuous two-step nucleation method.Initially,the C-S-H precursor is separated and dried,followed by im...The novel calcium-silicate-hydrate(C-S-H)/paraffin composite phase change materials were synthesized using a discontinuous two-step nucleation method.Initially,the C-S-H precursor is separated and dried,followed by immersion in an aqueous environment to transform it into C-S-H.This two-step nucleation approach results in C-S-H with a specific surface area of 497.2 m^(2)/g,achieved by preventing C-S-H foil overlapping and refining its pore structure.When impregnated with paraffin,the novel C-S-H/paraffin composite exhibits superior thermal properties,such as a higher potential heat value of 148.3 J/g and an encapsulation efficiency of 81.6%,outperforming conventional C-S-H.Moreover,the composite material demonstrates excellent cyclic performance,indicating its potential for building thermal storage compared to other paraffin-based composites.Compared with the conventional method,this simple technology,which only adds conversion and centrifugation steps,does not negatively impact preparation costs,the environment,and resource consumption.This study provides valuable theoretical insights for designing thermal storage concrete materials and advancing building heat management.展开更多
There has been a strong interest in the use of Phase Change Materials (PCMs) for the transient thermal abatement of high powered microprocessor.This paper presents a set of transient computational analysis for selecte...There has been a strong interest in the use of Phase Change Materials (PCMs) for the transient thermal abatement of high powered microprocessor.This paper presents a set of transient computational analysis for selected IC packages with the purpose of calibrating the merits of PCM in different configurations.The transient analysis of high powered microprocessors with heat sinks was performed as a benchmark for comparison with the same microprocessors fitted with PCM in the following configurations:a) PCM imbedded into the finned region of the heat sink,b) PCM mounted between the microprocessor and heat sink,c) sealed PCM underfill to the microprocessor and d) PCM fitted to the underside of the printed circuit board directly beneath the microprocessor.The analysis was performed using a commercial CFD tool together with an approximation to the phase change mechanism using the slope method.Results indicate the merit of each configuration.展开更多
基金The National Natural Science Foundation of China(No.52122802,52078126)Jiangsu Provincial Department of Science and Technology Innovation Support Program(No.BK20222004,BZ2022036).
文摘The novel calcium-silicate-hydrate(C-S-H)/paraffin composite phase change materials were synthesized using a discontinuous two-step nucleation method.Initially,the C-S-H precursor is separated and dried,followed by immersion in an aqueous environment to transform it into C-S-H.This two-step nucleation approach results in C-S-H with a specific surface area of 497.2 m^(2)/g,achieved by preventing C-S-H foil overlapping and refining its pore structure.When impregnated with paraffin,the novel C-S-H/paraffin composite exhibits superior thermal properties,such as a higher potential heat value of 148.3 J/g and an encapsulation efficiency of 81.6%,outperforming conventional C-S-H.Moreover,the composite material demonstrates excellent cyclic performance,indicating its potential for building thermal storage compared to other paraffin-based composites.Compared with the conventional method,this simple technology,which only adds conversion and centrifugation steps,does not negatively impact preparation costs,the environment,and resource consumption.This study provides valuable theoretical insights for designing thermal storage concrete materials and advancing building heat management.
文摘There has been a strong interest in the use of Phase Change Materials (PCMs) for the transient thermal abatement of high powered microprocessor.This paper presents a set of transient computational analysis for selected IC packages with the purpose of calibrating the merits of PCM in different configurations.The transient analysis of high powered microprocessors with heat sinks was performed as a benchmark for comparison with the same microprocessors fitted with PCM in the following configurations:a) PCM imbedded into the finned region of the heat sink,b) PCM mounted between the microprocessor and heat sink,c) sealed PCM underfill to the microprocessor and d) PCM fitted to the underside of the printed circuit board directly beneath the microprocessor.The analysis was performed using a commercial CFD tool together with an approximation to the phase change mechanism using the slope method.Results indicate the merit of each configuration.