The Experts below are selected from a list of 22827 Experts worldwide ranked by ideXlab platform
Jinkon Kim - One of the best experts on this subject based on the ideXlab platform.
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thermal characterizations of the Paraffin Wax low density polyethylene blends as a solid fuel
Thermochimica Acta, 2015Co-Authors: Soojong Kim, Heejang Moon, Jinkon KimAbstract:Abstract Thermal characterizations of a novel solid fuel for hybrid rocket application, based on the Paraffin Wax blends with low density polyethylene (LDPE) concentration of 5% (SF-5) and 10% (SF-10) were conducted. Both the increased regression rate in comparison with the polymeric fuel, and the improved combustion efficiency in comparison with the pure Paraffin fuel reveal that the blend fuels achieve higher combustion performance. The morphology of the shape stabilized Paraffin Wax/LDPE blends was characterized by the scanning electron microscopy (SEM). Although the SEM observation indicated the blends have uniform mixtures, they showed two degradation steps confirming the immiscibility of components in the crystalline phase from thermogravimetric analysis (TGA). The differential scanning calorimeter (DSC) results showed that the melting temperature of LDPE in the blends decreased with an increase of Paraffin Wax content. The decreasing total specific melting enthalpy of blended fuels with decreasing Paraffin Wax content is in fairly good agreement with the additive rule. In thermomechanical analysis (TMA), the linear coefficient of thermal expansion (LCTE) seems to decrease with an increase of LDPE loading, however, the loaded LDPE do merely affect the LCTE in case of the blends with low LDPE concentration. It was found that a blend of low concentration of LDPE with a relatively high concentration of Paraffin Wax can lead to a potential novel fuel for rocket application, a contrary case with respect to the field of phase change materials (PCM) where a blend of high concentration of LDPE is usually used with low concentration of Paraffin Wax.
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Thermal characterizations of the Paraffin Wax/low density polyethylene blends as a solid fuel
Thermochimica Acta, 2015Co-Authors: Soojong Kim, Heejang Moon, Jinkon KimAbstract:Thermal characterizations of a novel solid fuel for hybrid rocket application, based on the Paraffin Wax blends with low density polyethylene (LDPE) concentration of 5% (SF-5) and 10% (SF-10) were conducted. Both the increased regression rate in comparison with the polymeric fuel, and the improved combustion efficiency in comparison with the pure Paraffin fuel reveal that the blend fuels achieve higher combustion performance. The morphology of the shape stabilized Paraffin Wax/LDPE blends was characterized by the scanning electron microscopy (SEM). Although the SEM observation indicated the blends have uniform mixtures, they showed two degradation steps confirming the immiscibility of components in the crystalline phase from thermogravimetric analysis (TGA). The differential scanning calorimeter (DSC) results showed that the melting temperature of LDPE in the blends decreased with an increase of Paraffin Wax content. The decreasing total specific melting enthalpy of blended fuels with decreasing Paraffin Wax content is in fairly good agreement with the additive rule. In thermomechanical analysis (TMA), the linear coefficient of thermal expansion (LCTE) seems to decrease with an increase of LDPE loading, however, the loaded LDPE do merely affect the LCTE in case of the blends with low LDPE concentration. It was found that a blend of low concentration of LDPE with a relatively high concentration of Paraffin Wax can lead to a potential novel fuel for rocket application, a contrary case with respect to the field of phase change materials (PCM) where a blend of high concentration of LDPE is usually used with low concentration of Paraffin Wax.
Sizhong Li - One of the best experts on this subject based on the ideXlab platform.
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heat transfer enhancement of Paraffin Wax using graphite foam for thermal energy storage
Solar Energy Materials and Solar Cells, 2010Co-Authors: Yajuan Zhong, Sizhong LiAbstract:Mesophase pitch based graphite foams (GFs) with different thermal properties and pore-size were used to increase the thermal diffusivity of phase change material (PCM), Paraffin Wax, for latent heat thermal energy storage application. To predict the performance of the Paraffin-GFs as a thermal energy storage system, their structure, thermal diffusivity and latent heat were characterized. Results indicated that thermal diffusivity of the Paraffin-GF can be enhanced 190, 270, 500, and 570 times as compared with that of pure Paraffin Wax. Latent heat of Paraffin-GF systems increased with the increasing of the mass ratio of the Paraffin Wax in the composite. Moreover, pore-size and thickness of ligaments of the foam played a key role in improving the thermal diffusivity and the storage capacity of the Paraffin-GF system: small pore-size (less Paraffin Wax were filled) and thicker ligament in GF resulted in a higher thermal diffusivity; large pore-size (less Paraffin Wax were filled) and thinner ligament in GF resulted in a larger latent heat.
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heat transfer enhancement of Paraffin Wax using compressed expanded natural graphite for thermal energy storage
Carbon, 2010Co-Authors: Yajuan Zhong, Sizhong LiAbstract:Abstract Compressed expanded natural graphite (CENG) matrices with different densities were used to increase the thermal property of Paraffin Wax. To predict the performance of the Paraffin Wax/CENG composites as a thermal energy storage system, their structure, thermal conductivity and latent heat were characterized. Results indicated that the thermal conductivity of the composites can be 28–180× that of the pure Paraffin Wax. The existence of natural convection can reduce the time necessary for melting due to the anisotropy of the pore structure and thermal conductivity in CENG matrix. There are almost linear relationships between the thermal conductivity and the bulk density of the CENG matrix, and between the latent heat of the composite and the mass ratio of Paraffin Wax in the CENG matrix.
Soojong Kim - One of the best experts on this subject based on the ideXlab platform.
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thermal characterizations of the Paraffin Wax low density polyethylene blends as a solid fuel
Thermochimica Acta, 2015Co-Authors: Soojong Kim, Heejang Moon, Jinkon KimAbstract:Abstract Thermal characterizations of a novel solid fuel for hybrid rocket application, based on the Paraffin Wax blends with low density polyethylene (LDPE) concentration of 5% (SF-5) and 10% (SF-10) were conducted. Both the increased regression rate in comparison with the polymeric fuel, and the improved combustion efficiency in comparison with the pure Paraffin fuel reveal that the blend fuels achieve higher combustion performance. The morphology of the shape stabilized Paraffin Wax/LDPE blends was characterized by the scanning electron microscopy (SEM). Although the SEM observation indicated the blends have uniform mixtures, they showed two degradation steps confirming the immiscibility of components in the crystalline phase from thermogravimetric analysis (TGA). The differential scanning calorimeter (DSC) results showed that the melting temperature of LDPE in the blends decreased with an increase of Paraffin Wax content. The decreasing total specific melting enthalpy of blended fuels with decreasing Paraffin Wax content is in fairly good agreement with the additive rule. In thermomechanical analysis (TMA), the linear coefficient of thermal expansion (LCTE) seems to decrease with an increase of LDPE loading, however, the loaded LDPE do merely affect the LCTE in case of the blends with low LDPE concentration. It was found that a blend of low concentration of LDPE with a relatively high concentration of Paraffin Wax can lead to a potential novel fuel for rocket application, a contrary case with respect to the field of phase change materials (PCM) where a blend of high concentration of LDPE is usually used with low concentration of Paraffin Wax.
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Thermal characterizations of the Paraffin Wax/low density polyethylene blends as a solid fuel
Thermochimica Acta, 2015Co-Authors: Soojong Kim, Heejang Moon, Jinkon KimAbstract:Thermal characterizations of a novel solid fuel for hybrid rocket application, based on the Paraffin Wax blends with low density polyethylene (LDPE) concentration of 5% (SF-5) and 10% (SF-10) were conducted. Both the increased regression rate in comparison with the polymeric fuel, and the improved combustion efficiency in comparison with the pure Paraffin fuel reveal that the blend fuels achieve higher combustion performance. The morphology of the shape stabilized Paraffin Wax/LDPE blends was characterized by the scanning electron microscopy (SEM). Although the SEM observation indicated the blends have uniform mixtures, they showed two degradation steps confirming the immiscibility of components in the crystalline phase from thermogravimetric analysis (TGA). The differential scanning calorimeter (DSC) results showed that the melting temperature of LDPE in the blends decreased with an increase of Paraffin Wax content. The decreasing total specific melting enthalpy of blended fuels with decreasing Paraffin Wax content is in fairly good agreement with the additive rule. In thermomechanical analysis (TMA), the linear coefficient of thermal expansion (LCTE) seems to decrease with an increase of LDPE loading, however, the loaded LDPE do merely affect the LCTE in case of the blends with low LDPE concentration. It was found that a blend of low concentration of LDPE with a relatively high concentration of Paraffin Wax can lead to a potential novel fuel for rocket application, a contrary case with respect to the field of phase change materials (PCM) where a blend of high concentration of LDPE is usually used with low concentration of Paraffin Wax.
Yajuan Zhong - One of the best experts on this subject based on the ideXlab platform.
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heat transfer enhancement of Paraffin Wax using graphite foam for thermal energy storage
Solar Energy Materials and Solar Cells, 2010Co-Authors: Yajuan Zhong, Sizhong LiAbstract:Mesophase pitch based graphite foams (GFs) with different thermal properties and pore-size were used to increase the thermal diffusivity of phase change material (PCM), Paraffin Wax, for latent heat thermal energy storage application. To predict the performance of the Paraffin-GFs as a thermal energy storage system, their structure, thermal diffusivity and latent heat were characterized. Results indicated that thermal diffusivity of the Paraffin-GF can be enhanced 190, 270, 500, and 570 times as compared with that of pure Paraffin Wax. Latent heat of Paraffin-GF systems increased with the increasing of the mass ratio of the Paraffin Wax in the composite. Moreover, pore-size and thickness of ligaments of the foam played a key role in improving the thermal diffusivity and the storage capacity of the Paraffin-GF system: small pore-size (less Paraffin Wax were filled) and thicker ligament in GF resulted in a higher thermal diffusivity; large pore-size (less Paraffin Wax were filled) and thinner ligament in GF resulted in a larger latent heat.
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heat transfer enhancement of Paraffin Wax using compressed expanded natural graphite for thermal energy storage
Carbon, 2010Co-Authors: Yajuan Zhong, Sizhong LiAbstract:Abstract Compressed expanded natural graphite (CENG) matrices with different densities were used to increase the thermal property of Paraffin Wax. To predict the performance of the Paraffin Wax/CENG composites as a thermal energy storage system, their structure, thermal conductivity and latent heat were characterized. Results indicated that the thermal conductivity of the composites can be 28–180× that of the pure Paraffin Wax. The existence of natural convection can reduce the time necessary for melting due to the anisotropy of the pore structure and thermal conductivity in CENG matrix. There are almost linear relationships between the thermal conductivity and the bulk density of the CENG matrix, and between the latent heat of the composite and the mass ratio of Paraffin Wax in the CENG matrix.
Arun S. Mujumdar - One of the best experts on this subject based on the ideXlab platform.
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NUMERICAL PERFORMANCE STUDY OF Paraffin Wax DISPERSED WITH ALUMINA IN A CONCENTRIC PIPE LATENT HEAT STORAGE SYSTEM
Thermal Science, 2013Co-Authors: Arasu Amirtham Valan, Agus P. Sasmito, Arun S. MujumdarAbstract:Latent heat energy storage systems using Paraffin Wax could have lower heat transfer rates during melting/freezing processes due to its inherent low thermal conductivity. The thermal conductivity of Paraffin Wax can be enhanced by employing high conductivity materials such as alumina (Al2O3). A numerical analysis has been carried out to study the performance enhancement of Paraffin Wax with nanoalumina (Al2O3) particles in comparison with simple Paraffin Wax in a concentric double pipe heat exchanger. Numerical analysis indicates that the charge-discharge rates of thermal energy can be greatly enhanced using Paraffin Wax with alumina as compared with a simple Paraffin Wax as PCM.
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THERMAL PERFORMANCE ENHANCEMENT OF Paraffin Wax WITH AL2O3 AND CuO NANOPARTICLES – A NUMERICAL STUDY
Frontiers in Heat and Mass Transfer, 2012Co-Authors: Amirtham Valan Arasu, Agus P. Sasmito, Arun S. MujumdarAbstract:The heat transfer enhancement of Paraffin Wax, a cheap and widely used latent heat thermal energy storage material, using nanoparticles is investigated. The effects of nanoparticle volume fraction on both the melting and solidification rates of Paraffin Wax are analysed and compared for Al2O3 and CuO nanoparticles. Present results show that dispersing nanoparticles in smaller volumetric fractions increase the heat transfer rate. The enhancement in thermal performance of Paraffin Wax is greater for Al2O3 compared with that for CuO nanoparticles. .
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thermal performance enhancement of Paraffin Wax with al2o3 and cuo nanoparticles a numerical study
Frontiers in Heat and Mass Transfer, 2012Co-Authors: Amirtham Valan Arasu, Agus P. Sasmito, Arun S. MujumdarAbstract:The heat transfer enhancement of Paraffin Wax, a cheap and widely used latent heat thermal energy storage material, using nanoparticles is investigated. The effects of nanoparticle volume fraction on both the melting and solidification rates of Paraffin Wax are analysed and compared for Al2O3 and CuO nanoparticles. Present results show that dispersing nanoparticles in smaller volumetric fractions increase the heat transfer rate. The enhancement in thermal performance of Paraffin Wax is greater for Al2O3 compared with that for CuO nanoparticles. .
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numerical study on melting of Paraffin Wax with al2o3 in a square enclosure
International Communications in Heat and Mass Transfer, 2012Co-Authors: Valan A Arasu, Arun S. MujumdarAbstract:Abstract The melting of Paraffin Wax dispersed with Al2O3 that is heated from one side of a square enclosure with dimensions of 25 mm × 25 mm is investigated numerically. The stream function, isotherms and liquid–solid interface at different stages of the melting process are presented and discussed. The effect of orientation of the heating surfaces of a square cavity and the volumetric concentration of Al2O3 in Paraffin Wax on the melting performance of the latent heat storage system is analysed.
