The Experts below are selected from a list of 1989 Experts worldwide ranked by ideXlab platform
Yulong Ding - One of the best experts on this subject based on the ideXlab platform.
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numerical study of solidification in a plate heat exchange device with a Zigzag Configuration containing multiple phase change materials
Energies, 2016Co-Authors: Peilun Wang, Zhijian Peng, Yun Huang, Xingang Zheng, Yi Wang, Yulong DingAbstract:Latent heat thermal energy storage (TES) plays an important role in the advocation of TES in contrast to sensible energy storage because of the large storage energy densities per unit mass/volume possible at a nearly constant thermal energy. In the current study, a heat exchange device with a Zigzag Configuration containing multiple phase-change-materials (m-PCMs) was considered, and an experimental system was built to validate the model for a single PCM. A two-dimensional numerical model was developed using the ANSYS Fluent 14.0 software program. The energy fractions method was put forward to calculate the average Ste number and the influence of Re and Ste numbers on the discharge process were studied. The influence of phase change temperature among m-PCMs on the solidification process has also been studied. A new boundary condition was defined to determine the combined effect of the Re and Ste numbers on the discharging process. The modelling results show that for a given input power, the Ste (or Re) number has a significant impact on the discharging process; however, the period value of inlet velocity has almost no impact on it. Besides, the Zigzag plate with m-PCMs has a good impact on the temperature shock as “filter action” in the discharging process.
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thermal energy charging behaviour of a heat exchange device with a Zigzag plate Configuration containing multi phase change materials m pcms
Applied Energy, 2015Co-Authors: Peilun Wang, Zhijian Peng, Xiang Wang, Yun Huang, Yulong DingAbstract:This paper concerns heat exchange devices with a Zigzag Configuration containing multi-phase change materials (m-PCMs). A two dimensional mathematical model was established to model the charging behaviour. An experimental system was built to validate the model. The modelling results agree reasonably well with the experimental data for a single PCM, establishing confidence in the model. Extensive modelling was then carried out under different conditions. The results show that the use of m-PCMs intensifies the charging process in comparison with the use of a single PCM. Given other conditions, a larger phase change temperature difference between the m-PCMs gives a more remarkable enhancement of the charging process, and the use of m-PCMs with an unequal mass ratio gives further intensification. The modelling results also show that, for a given input power, an optimal fluid velocity exists for obtaining a high rate of the melting process. (C) 2014 Elsevier Ltd. All rights reserved.
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Thermal energy charging behaviour of a heat exchange device with a Zigzag plate Configuration containing multi-phase-change-materials (m-PCMs)
Applied Energy, 2015Co-Authors: Peilun Wang, Chuan Li, Zhijian Peng, Xiang Wang, Yun Huang, Yulong DingAbstract:This paper concerns heat exchange devices with a Zigzag Configuration containing multi-phase change materials (m-PCMs). A two dimensional mathematical model was established to model the charging behaviour. An experimental system was built to validate the model. The modelling results agree reasonably well with the experimental data for a single PCM, establishing confidence in the model. Extensive modelling was then carried out under different conditions. The results show that the use of m-PCMs intensifies the charging process in comparison with the use of a single PCM. Given other conditions, a larger phase change temperature difference between the m-PCMs gives a more remarkable enhancement of the charging process, and the use of m-PCMs with an unequal mass ratio gives further intensification. The modelling results also show that, for a given input power, an optimal fluid velocity exists for obtaining a high rate of the melting process.
Peilun Wang - One of the best experts on this subject based on the ideXlab platform.
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numerical study of solidification in a plate heat exchange device with a Zigzag Configuration containing multiple phase change materials
Energies, 2016Co-Authors: Peilun Wang, Zhijian Peng, Yun Huang, Xingang Zheng, Yi Wang, Yulong DingAbstract:Latent heat thermal energy storage (TES) plays an important role in the advocation of TES in contrast to sensible energy storage because of the large storage energy densities per unit mass/volume possible at a nearly constant thermal energy. In the current study, a heat exchange device with a Zigzag Configuration containing multiple phase-change-materials (m-PCMs) was considered, and an experimental system was built to validate the model for a single PCM. A two-dimensional numerical model was developed using the ANSYS Fluent 14.0 software program. The energy fractions method was put forward to calculate the average Ste number and the influence of Re and Ste numbers on the discharge process were studied. The influence of phase change temperature among m-PCMs on the solidification process has also been studied. A new boundary condition was defined to determine the combined effect of the Re and Ste numbers on the discharging process. The modelling results show that for a given input power, the Ste (or Re) number has a significant impact on the discharging process; however, the period value of inlet velocity has almost no impact on it. Besides, the Zigzag plate with m-PCMs has a good impact on the temperature shock as “filter action” in the discharging process.
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thermal energy charging behaviour of a heat exchange device with a Zigzag plate Configuration containing multi phase change materials m pcms
Applied Energy, 2015Co-Authors: Peilun Wang, Zhijian Peng, Xiang Wang, Yun Huang, Yulong DingAbstract:This paper concerns heat exchange devices with a Zigzag Configuration containing multi-phase change materials (m-PCMs). A two dimensional mathematical model was established to model the charging behaviour. An experimental system was built to validate the model. The modelling results agree reasonably well with the experimental data for a single PCM, establishing confidence in the model. Extensive modelling was then carried out under different conditions. The results show that the use of m-PCMs intensifies the charging process in comparison with the use of a single PCM. Given other conditions, a larger phase change temperature difference between the m-PCMs gives a more remarkable enhancement of the charging process, and the use of m-PCMs with an unequal mass ratio gives further intensification. The modelling results also show that, for a given input power, an optimal fluid velocity exists for obtaining a high rate of the melting process. (C) 2014 Elsevier Ltd. All rights reserved.
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Thermal energy charging behaviour of a heat exchange device with a Zigzag plate Configuration containing multi-phase-change-materials (m-PCMs)
Applied Energy, 2015Co-Authors: Peilun Wang, Chuan Li, Zhijian Peng, Xiang Wang, Yun Huang, Yulong DingAbstract:This paper concerns heat exchange devices with a Zigzag Configuration containing multi-phase change materials (m-PCMs). A two dimensional mathematical model was established to model the charging behaviour. An experimental system was built to validate the model. The modelling results agree reasonably well with the experimental data for a single PCM, establishing confidence in the model. Extensive modelling was then carried out under different conditions. The results show that the use of m-PCMs intensifies the charging process in comparison with the use of a single PCM. Given other conditions, a larger phase change temperature difference between the m-PCMs gives a more remarkable enhancement of the charging process, and the use of m-PCMs with an unequal mass ratio gives further intensification. The modelling results also show that, for a given input power, an optimal fluid velocity exists for obtaining a high rate of the melting process.
Zhijian Peng - One of the best experts on this subject based on the ideXlab platform.
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numerical study of solidification in a plate heat exchange device with a Zigzag Configuration containing multiple phase change materials
Energies, 2016Co-Authors: Peilun Wang, Zhijian Peng, Yun Huang, Xingang Zheng, Yi Wang, Yulong DingAbstract:Latent heat thermal energy storage (TES) plays an important role in the advocation of TES in contrast to sensible energy storage because of the large storage energy densities per unit mass/volume possible at a nearly constant thermal energy. In the current study, a heat exchange device with a Zigzag Configuration containing multiple phase-change-materials (m-PCMs) was considered, and an experimental system was built to validate the model for a single PCM. A two-dimensional numerical model was developed using the ANSYS Fluent 14.0 software program. The energy fractions method was put forward to calculate the average Ste number and the influence of Re and Ste numbers on the discharge process were studied. The influence of phase change temperature among m-PCMs on the solidification process has also been studied. A new boundary condition was defined to determine the combined effect of the Re and Ste numbers on the discharging process. The modelling results show that for a given input power, the Ste (or Re) number has a significant impact on the discharging process; however, the period value of inlet velocity has almost no impact on it. Besides, the Zigzag plate with m-PCMs has a good impact on the temperature shock as “filter action” in the discharging process.
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thermal energy charging behaviour of a heat exchange device with a Zigzag plate Configuration containing multi phase change materials m pcms
Applied Energy, 2015Co-Authors: Peilun Wang, Zhijian Peng, Xiang Wang, Yun Huang, Yulong DingAbstract:This paper concerns heat exchange devices with a Zigzag Configuration containing multi-phase change materials (m-PCMs). A two dimensional mathematical model was established to model the charging behaviour. An experimental system was built to validate the model. The modelling results agree reasonably well with the experimental data for a single PCM, establishing confidence in the model. Extensive modelling was then carried out under different conditions. The results show that the use of m-PCMs intensifies the charging process in comparison with the use of a single PCM. Given other conditions, a larger phase change temperature difference between the m-PCMs gives a more remarkable enhancement of the charging process, and the use of m-PCMs with an unequal mass ratio gives further intensification. The modelling results also show that, for a given input power, an optimal fluid velocity exists for obtaining a high rate of the melting process. (C) 2014 Elsevier Ltd. All rights reserved.
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Thermal energy charging behaviour of a heat exchange device with a Zigzag plate Configuration containing multi-phase-change-materials (m-PCMs)
Applied Energy, 2015Co-Authors: Peilun Wang, Chuan Li, Zhijian Peng, Xiang Wang, Yun Huang, Yulong DingAbstract:This paper concerns heat exchange devices with a Zigzag Configuration containing multi-phase change materials (m-PCMs). A two dimensional mathematical model was established to model the charging behaviour. An experimental system was built to validate the model. The modelling results agree reasonably well with the experimental data for a single PCM, establishing confidence in the model. Extensive modelling was then carried out under different conditions. The results show that the use of m-PCMs intensifies the charging process in comparison with the use of a single PCM. Given other conditions, a larger phase change temperature difference between the m-PCMs gives a more remarkable enhancement of the charging process, and the use of m-PCMs with an unequal mass ratio gives further intensification. The modelling results also show that, for a given input power, an optimal fluid velocity exists for obtaining a high rate of the melting process.
Yun Huang - One of the best experts on this subject based on the ideXlab platform.
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numerical study of solidification in a plate heat exchange device with a Zigzag Configuration containing multiple phase change materials
Energies, 2016Co-Authors: Peilun Wang, Zhijian Peng, Yun Huang, Xingang Zheng, Yi Wang, Yulong DingAbstract:Latent heat thermal energy storage (TES) plays an important role in the advocation of TES in contrast to sensible energy storage because of the large storage energy densities per unit mass/volume possible at a nearly constant thermal energy. In the current study, a heat exchange device with a Zigzag Configuration containing multiple phase-change-materials (m-PCMs) was considered, and an experimental system was built to validate the model for a single PCM. A two-dimensional numerical model was developed using the ANSYS Fluent 14.0 software program. The energy fractions method was put forward to calculate the average Ste number and the influence of Re and Ste numbers on the discharge process were studied. The influence of phase change temperature among m-PCMs on the solidification process has also been studied. A new boundary condition was defined to determine the combined effect of the Re and Ste numbers on the discharging process. The modelling results show that for a given input power, the Ste (or Re) number has a significant impact on the discharging process; however, the period value of inlet velocity has almost no impact on it. Besides, the Zigzag plate with m-PCMs has a good impact on the temperature shock as “filter action” in the discharging process.
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thermal energy charging behaviour of a heat exchange device with a Zigzag plate Configuration containing multi phase change materials m pcms
Applied Energy, 2015Co-Authors: Peilun Wang, Zhijian Peng, Xiang Wang, Yun Huang, Yulong DingAbstract:This paper concerns heat exchange devices with a Zigzag Configuration containing multi-phase change materials (m-PCMs). A two dimensional mathematical model was established to model the charging behaviour. An experimental system was built to validate the model. The modelling results agree reasonably well with the experimental data for a single PCM, establishing confidence in the model. Extensive modelling was then carried out under different conditions. The results show that the use of m-PCMs intensifies the charging process in comparison with the use of a single PCM. Given other conditions, a larger phase change temperature difference between the m-PCMs gives a more remarkable enhancement of the charging process, and the use of m-PCMs with an unequal mass ratio gives further intensification. The modelling results also show that, for a given input power, an optimal fluid velocity exists for obtaining a high rate of the melting process. (C) 2014 Elsevier Ltd. All rights reserved.
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Thermal energy charging behaviour of a heat exchange device with a Zigzag plate Configuration containing multi-phase-change-materials (m-PCMs)
Applied Energy, 2015Co-Authors: Peilun Wang, Chuan Li, Zhijian Peng, Xiang Wang, Yun Huang, Yulong DingAbstract:This paper concerns heat exchange devices with a Zigzag Configuration containing multi-phase change materials (m-PCMs). A two dimensional mathematical model was established to model the charging behaviour. An experimental system was built to validate the model. The modelling results agree reasonably well with the experimental data for a single PCM, establishing confidence in the model. Extensive modelling was then carried out under different conditions. The results show that the use of m-PCMs intensifies the charging process in comparison with the use of a single PCM. Given other conditions, a larger phase change temperature difference between the m-PCMs gives a more remarkable enhancement of the charging process, and the use of m-PCMs with an unequal mass ratio gives further intensification. The modelling results also show that, for a given input power, an optimal fluid velocity exists for obtaining a high rate of the melting process.
Raphael Lavi - One of the best experts on this subject based on the ideXlab platform.
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diamond cooling of high power diode pumped solid state lasers
IEEE Journal of Quantum Electronics, 2004Co-Authors: Y Tzuk, Alon Tal, S Goldring, Yaakov Glick, E Lebiush, Guy Kaufman, Raphael LaviAbstract:We have demonstrated the feasibility of cooling high-power solid-state lasers with diamond windows, whose thermal conductivity is about two orders of magnitude higher than that of sapphire. An output power of 200 W was achieved from a single Nd:YVO/sub 4/ slab in a Zigzag Configuration when pumped with 600-W diodes at 808 nm. The maximum output power previously reported in the literature using conventional cooling schemes is only about 100 W. A 2.3/spl times/4/spl times/24 mm/sup 3/ slab was pumped from its broad side (4/spl times/24 mm/sup 2/) through a 0.3-mm-thick optical diamond window placed in close contact with the lasing crystal. The diamond window, held in a water-cooled copper housing, acted as a heat conductor. The other broad side of the crystal was cooled directly by its water-cooled copper housing. Since pumping and cooling were along the same axis, a Cartesian thermal gradient was achieved, while the Zigzag scheme was used to minimize thermal lensing. By using a BBO Q-switch, 70-W average power was obtained at 20 kHz with a pulse width of 19 ns and with a beam quality of 3 and 12 times the diffraction limit in the Zigzag and transverse directions, respectively. The output of a two-head Configuration was 295 W. In addition, a cavity was designed to achieve increased beam quality and 133 W was accomplished with a beam quality of 2 and 7.5 times diffraction-limited on the Zigzag and nonZigzag axes, respectively. Operating this cavity with an RTP Q-switch produced 114 W with a beam quality of 1.5 and 9.5 on the respective two axes.
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diamond cooling of high power diode pumped solid state lasers
High-power lasers and applications, 2003Co-Authors: Y Tzuk, Alon Tal, S Goldring, Yaakov Glick, E Lebiush, Guy Kaufman, Raphael LaviAbstract:We have demonstrated the feasibility of cooling high power solid-stae lasers with diamond windows, whose thermal conductivity is about two orders of magnitude higher than sapphire's. An output power of 200Watt was achieved froma single Nd:YVO4 slab in a Zigzag Configuration when pumped with 600Watt diodes at 808nm. The maximum output power reported in the literature with conventional cooling schemes is about 50W. A 2.3x4x24mm3 slab was pumped from its broad side (4x24 mm2) through a 0.3mm thick optical diamond window placed in close contact with the lasing crystal. The diamond window, held in a water-cooled copper housing acted as a heat conductor. The other broad side of the crystal was cooled directly by its water-cooled copper housing. Since pumping and cooling were along the same axis, a Cartesian thermal gradient was achieved, while the Zigzag scheme was used to minimize thermal lensing. By using a BBO Q-switch, 70Watt average power was obtained at 20kHz with a pulse width of 19msec and with a beam quality of 3 and 12 times diffraction limit in the Zigzag and transverse directions respectively. The output of a two-head Configuration was 295Watt.
