The Experts below are selected from a list of 183606 Experts worldwide ranked by ideXlab platform
Manop Panapoy - One of the best experts on this subject based on the ideXlab platform.
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comments on Temperature Profiles of pp melt in the barrel of a twin screw extruder
Polymer Testing, 2001Co-Authors: Narongrit Sombatsompop, Manop PanapoyAbstract:The radial Temperature Profiles of a polypropylene melt were examined at a point along the barrel of a twin screw extruder, using a novel thermocouple sensor. The flow patterns of the polymer melt were also investigated, the results being used to explain the changes in Temperature of the melt during the flow. It was found that the melt Temperature Profiles and the flow patterns of the polymer melt were closely related. The heat conduction, shear heating, and the flow length of the material in the barrel of the extruder had considerable effects on the melt Temperature.
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Effect of screw rotating speed on polymer melt Temperature Profiles in twin screw extruder
Journal of Materials Science, 2000Co-Authors: Narongrit Sombatsompop, Manop PanapoyAbstract:The effect of screw rotating speed on two-dimensional Temperature Profiles of flowing polypropylene melt was investigated in the barrel of a counter-rotating twin screw extruder using a designed experimental apparatus and a thermocouple Temperature sensing device, the experimental apparatus being connected to a high speed data logger and a computer. The flow patterns of the polymer melt in the barrel of the extruder were also revealed. The changes in melt Temperature Profiles with extruding time were discussed in terms of flow patterns of the polymer melt during the flow, the increase in melt Temperature being closely associated with total flow length of the melt, and shear heating and heat conduction effects.
Oliver Reitebuch - One of the best experts on this subject based on the ideXlab platform.
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Daytime measurements of atmospheric Temperature Profiles (2-15 km) by lidar utilizing Rayleigh-Brillouin scattering
Optics Letters, 2014Co-Authors: Benjamin Witschas, Christian Lemmerz, Oliver ReitebuchAbstract:In this Letter, we report on a novel method for measuring atmospheric Temperature Profiles by lidar during daytime for heights of 2–15.3 km, with a vertical resolution of 0.3–2.2 km, using Rayleigh–Brillouin scattering. The measurements are performed by scanning a laser (λ=355 nm) over a 12 GHz range and using a Fabry–Perot interferometer as discriminator. The Temperature is derived by using a new analytical line shape model assuming standard atmospheric pressure conditions. Two exemplary Temperature Profiles resulting from measurements over 14 and 27 min are shown. A comparison with radiosonde Temperature measurements shows reasonable agreement. In cloud-free conditions, the Temperature difference reaches up to 5 K within the boundary layer, and is smaller than 2.5 K above. The statistical error of the derived Temperatures is between 0.15 and 1.5 K.
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Lidar measurements of atmospheric Temperature Profiles (2-15 km) by utilizing Rayleigh-Brillouin scattering
Lidar Technologies Techniques and Measurements for Atmospheric Remote Sensing IX, 2013Co-Authors: Benjamin Witschas, Christian Lemmerz, Oliver ReitebuchAbstract:In this paper, we report on a novel method for measurements of atmospheric Temperature Profiles during daytime from 2 km up to 15.3 km with a vertical resolution between 0.3 km to 2.2 km by lidar (light detection and ranging) using Rayleigh-Brillouin scattering. The spectra of Rayleigh-Brillouin scattered light are measured by scanning a laser (λ = 355 nm) over a 12 GHz range and using a single Fabry-Perot interferometer as frequency discriminator. Temperature is derived by analyzing the measured Rayleigh-Brillouin spectra with an analytical line shape model and assuming standard-atmospherical pressure conditions. Two exemplary Temperature Profiles resulting from measurements over 14 min and 27 min are shown. A comparison to radiosonde Temperature measurements show reasonable agreement. The Temperature difference reaches up to 5 K within the boundary layer and is smaller than 2.5 K above. The statistical error is calculated with a maximum likelihood estimator and varies between 0.15 K and 1.5 K.
Narongrit Sombatsompop - One of the best experts on this subject based on the ideXlab platform.
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comments on Temperature Profiles of pp melt in the barrel of a twin screw extruder
Polymer Testing, 2001Co-Authors: Narongrit Sombatsompop, Manop PanapoyAbstract:The radial Temperature Profiles of a polypropylene melt were examined at a point along the barrel of a twin screw extruder, using a novel thermocouple sensor. The flow patterns of the polymer melt were also investigated, the results being used to explain the changes in Temperature of the melt during the flow. It was found that the melt Temperature Profiles and the flow patterns of the polymer melt were closely related. The heat conduction, shear heating, and the flow length of the material in the barrel of the extruder had considerable effects on the melt Temperature.
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Effect of screw rotating speed on polymer melt Temperature Profiles in twin screw extruder
Journal of Materials Science, 2000Co-Authors: Narongrit Sombatsompop, Manop PanapoyAbstract:The effect of screw rotating speed on two-dimensional Temperature Profiles of flowing polypropylene melt was investigated in the barrel of a counter-rotating twin screw extruder using a designed experimental apparatus and a thermocouple Temperature sensing device, the experimental apparatus being connected to a high speed data logger and a computer. The flow patterns of the polymer melt in the barrel of the extruder were also revealed. The changes in melt Temperature Profiles with extruding time were discussed in terms of flow patterns of the polymer melt during the flow, the increase in melt Temperature being closely associated with total flow length of the melt, and shear heating and heat conduction effects.
Benjamin Witschas - One of the best experts on this subject based on the ideXlab platform.
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Daytime measurements of atmospheric Temperature Profiles (2-15 km) by lidar utilizing Rayleigh-Brillouin scattering
Optics Letters, 2014Co-Authors: Benjamin Witschas, Christian Lemmerz, Oliver ReitebuchAbstract:In this Letter, we report on a novel method for measuring atmospheric Temperature Profiles by lidar during daytime for heights of 2–15.3 km, with a vertical resolution of 0.3–2.2 km, using Rayleigh–Brillouin scattering. The measurements are performed by scanning a laser (λ=355 nm) over a 12 GHz range and using a Fabry–Perot interferometer as discriminator. The Temperature is derived by using a new analytical line shape model assuming standard atmospheric pressure conditions. Two exemplary Temperature Profiles resulting from measurements over 14 and 27 min are shown. A comparison with radiosonde Temperature measurements shows reasonable agreement. In cloud-free conditions, the Temperature difference reaches up to 5 K within the boundary layer, and is smaller than 2.5 K above. The statistical error of the derived Temperatures is between 0.15 and 1.5 K.
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Lidar measurements of atmospheric Temperature Profiles (2-15 km) by utilizing Rayleigh-Brillouin scattering
Lidar Technologies Techniques and Measurements for Atmospheric Remote Sensing IX, 2013Co-Authors: Benjamin Witschas, Christian Lemmerz, Oliver ReitebuchAbstract:In this paper, we report on a novel method for measurements of atmospheric Temperature Profiles during daytime from 2 km up to 15.3 km with a vertical resolution between 0.3 km to 2.2 km by lidar (light detection and ranging) using Rayleigh-Brillouin scattering. The spectra of Rayleigh-Brillouin scattered light are measured by scanning a laser (λ = 355 nm) over a 12 GHz range and using a single Fabry-Perot interferometer as frequency discriminator. Temperature is derived by analyzing the measured Rayleigh-Brillouin spectra with an analytical line shape model and assuming standard-atmospherical pressure conditions. Two exemplary Temperature Profiles resulting from measurements over 14 min and 27 min are shown. A comparison to radiosonde Temperature measurements show reasonable agreement. The Temperature difference reaches up to 5 K within the boundary layer and is smaller than 2.5 K above. The statistical error is calculated with a maximum likelihood estimator and varies between 0.15 K and 1.5 K.
Kathleen Beyer - One of the best experts on this subject based on the ideXlab platform.
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Projected changes in vertical Temperature Profiles for Australasia
Climate Dynamics, 2020Co-Authors: Jason P. Evans, Giovanni Di Virgilio, Nidhi Nishant, Alejandro Di Luca, Nicholas Herold, Stephanie M. Downes, Eugene Tam, Kathleen BeyerAbstract:The vertical Temperature profile in the atmosphere reflects a balance between radiative and convective processes and interactions with the oceanic and land surfaces. Changes in vertical Temperature Profiles can affect atmospheric stability, which in turn can impact various aspects of weather systems. In this study, we analyzed recent-past trends of Temperature over the Australian region using a homogenized monthly upper-air Temperature dataset and four reanalysis datasets (NCEP, ERA-Interim, JRA-55 and MERRA). We also used outputs of 12 historical and future regional climate model (RCM) simulations from the NSW/ACT (New South Wales/Australian Capital Territory) Regional Climate Modelling (NARCliM) project and 6 RCM simulations from the CORDEX (Coordinated Regional Downscaling Experiment) Australasian project to investigate projected changes in vertical Temperature Profiles. The results show that the currently observed positive trend in the troposphere and negative trend in the lower stratosphere will continue in the future with significant warming over the whole troposphere and largest over the middle to upper troposphere. The increasing Temperatures are found to be latitude-dependent with clear seasonal variations, and a strong diurnal variation for the near surface layers and upper levels in tropical regions. Changes in the diurnal variability indicate that near surface layers will be less stable in the afternoon leading to conditions favoring convective systems and more stable in the early morning which is favorable for Temperature inversions. The largest differences of future changes in Temperature between the simulations are associated with the driving GCMs, suggesting that large-scale circulation plays a dominant role in regional atmospheric Temperature change.
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Projected changes in vertical Temperature Profiles for Australasia
Climate Dynamics, 2020Co-Authors: Fei Ji, Jason P. Evans, Giovanni Di Virgilio, Nidhi Nishant, Alejandro Di Luca, Nicholas Herold, Stephanie M. Downes, Kathleen BeyerAbstract:The vertical Temperature profile in the atmosphere reflects a balance between radiative and convective processes and interactions with the oceanic and land surfaces. Changes in vertical Temperature Profiles can affect atmospheric stability, which in turn can impact various aspects of weather systems. In this study, we analyzed recent-past trends of Temperature over the Australian region using a homogenized monthly upper-air Temperature dataset and four reanalysis datasets (NCEP, ERA-Interim, JRA-55 and MERRA). We also used outputs of 12 historical and future regional climate model (RCM) simulations from the NSW/ACT (New South Wales/Australian Capital Territory) Regional Climate Modelling (NARCliM) project and 6 RCM simulations from the CORDEX (Coordinated Regional Downscaling Experiment) Australasian project to investigate projected changes in vertical Temperature Profiles. The results show that the currently observed positive trend in the troposphere and negative trend in the lower stratosphere will continue in the future with significant warming over the whole troposphere and largest over the middle to upper troposphere. The increasing Temperatures are found to be latitude-dependent with clear seasonal variations, and a strong diurnal variation for the near surface layers and upper levels in tropical regions. Changes in the diurnal variability indicate that near surface layers will be less stable in the afternoon leading to conditions favoring convective systems and more stable in the early morning which is favorable for Temperature inversions. The largest differences of future changes in Temperature between the simulations are associated with the driving GCMs, suggesting that large-scale circulation plays a dominant role in regional atmospheric Temperature change.
