The Experts below are selected from a list of 108 Experts worldwide ranked by ideXlab platform

Diego Perugini - One of the best experts on this subject based on the ideXlab platform.

  • volcanic ash generation effects of componentry particle Size and conduit geometry on Size Reduction Processes
    Earth and Planetary Science Letters, 2019
    Co-Authors: Joali Paredesmarino, Bettina Scheu, Cristian Montanaro, A Arciniegaceballos, Donald B Dingwell, Diego Perugini
    Abstract:

    Abstract Grain Size distributions (GSD) of pyroclastic materials are the product of Processes ranging from primary fragmentation efficiency to tephra transport. As such, a detailed description of their physical and chemical state can provide pivotal information regarding such Processes. By constraining the GSD of volcanic deposits one can thereby deliver powerful constraints on the energetics and dynamics of eruptions. In order to do so we must distinguish between two primary controls: 1) fragmentation of magma to tephra, and 2) secondary transport-related Processes (such as abrasion and comminution), within the conduit and until deposition of the particles. Variations in particle interactions in the conduit together with conduit geometry, may be major factors in modifying the GSD. As in all physicochemical Processes, for eruptive dynamics an experimental basis is an essential element of calibration and quantification. Here, we have conducted the first experimental investigation linking fragmentation and ash production via the influence of 1) particle-componentry and particle-Size, and 2) the conduit geometry (constricted versus unconstricted) on the GSD. Rapid decompression experiments with loose tephra material from the fall deposit of Pomici Principali eruption (10.3 ka, Campi Flegrei) have been conducted in an optically transparent setup that enables the optical monitoring of particle dynamics with a high-speed camera. The samples employed can be classified into two main groups; 1) pumices, and 2) dense clasts (including crystals, lava clasts and wall rock fragments). Our results indicate that 1) a conduit diameter constriction (simulating obstacles in the conduit walls) is likely to reduce the average diameter of individual clasts and increase the generation of ash (

Cristian Montanaro - One of the best experts on this subject based on the ideXlab platform.

  • volcanic ash generation effects of componentry particle Size and conduit geometry on Size Reduction Processes
    Earth and Planetary Science Letters, 2019
    Co-Authors: Joali Paredesmarino, Bettina Scheu, Cristian Montanaro, A Arciniegaceballos, Donald B Dingwell, Diego Perugini
    Abstract:

    Abstract Grain Size distributions (GSD) of pyroclastic materials are the product of Processes ranging from primary fragmentation efficiency to tephra transport. As such, a detailed description of their physical and chemical state can provide pivotal information regarding such Processes. By constraining the GSD of volcanic deposits one can thereby deliver powerful constraints on the energetics and dynamics of eruptions. In order to do so we must distinguish between two primary controls: 1) fragmentation of magma to tephra, and 2) secondary transport-related Processes (such as abrasion and comminution), within the conduit and until deposition of the particles. Variations in particle interactions in the conduit together with conduit geometry, may be major factors in modifying the GSD. As in all physicochemical Processes, for eruptive dynamics an experimental basis is an essential element of calibration and quantification. Here, we have conducted the first experimental investigation linking fragmentation and ash production via the influence of 1) particle-componentry and particle-Size, and 2) the conduit geometry (constricted versus unconstricted) on the GSD. Rapid decompression experiments with loose tephra material from the fall deposit of Pomici Principali eruption (10.3 ka, Campi Flegrei) have been conducted in an optically transparent setup that enables the optical monitoring of particle dynamics with a high-speed camera. The samples employed can be classified into two main groups; 1) pumices, and 2) dense clasts (including crystals, lava clasts and wall rock fragments). Our results indicate that 1) a conduit diameter constriction (simulating obstacles in the conduit walls) is likely to reduce the average diameter of individual clasts and increase the generation of ash (

L. Torres Quevedo - One of the best experts on this subject based on the ideXlab platform.

  • Development of an ultrasonic high-pressure roller press
    2020
    Co-Authors: L. Torres Quevedo
    Abstract:

    It is widely known that particle Size Reduction Processes have a low energetic e9ciency. In this paper, we present experimental results obtained by a new grinding machine using ultrasound to enhance the performance of a roller mill. The required energy consumption for a comminution operation appears to be signi=cantly reduced by careful application of an ultrasonic =eld in the grinding zone. A lower stress on the shafts and a Reduction of the required torque were also observed. The lower mechanical stress should also cause less abrasive wear on the rolls. ? 2003 Elsevier Ltd. All rights reserved.

F. Montoya-vitini - One of the best experts on this subject based on the ideXlab platform.

  • Development of an ultrasonic high-pressure roller press
    Chemical Engineering Science, 2003
    Co-Authors: L. Gaete-garretón, Y. Vargas-hernandez, A. Chamayou, John A. Dodds, W. Valderama-reyes, F. Montoya-vitini
    Abstract:

    It is widely known that particle Size Reduction Processes have a low energetic efficiency. In this paper, we present experimental results obtained by a new grinding machine using ultrasound to enhance the performance of a roller mill. The required energy consumption for a comminution operation appears to be significantly reduced by careful application of an ultrasonic field in the grinding zone. A lower stress on the shafts and a Reduction of the required torque were also observed. The lower mechanical stress should also cause less abrasive wear on the rolls.

Joali Paredesmarino - One of the best experts on this subject based on the ideXlab platform.

  • volcanic ash generation effects of componentry particle Size and conduit geometry on Size Reduction Processes
    Earth and Planetary Science Letters, 2019
    Co-Authors: Joali Paredesmarino, Bettina Scheu, Cristian Montanaro, A Arciniegaceballos, Donald B Dingwell, Diego Perugini
    Abstract:

    Abstract Grain Size distributions (GSD) of pyroclastic materials are the product of Processes ranging from primary fragmentation efficiency to tephra transport. As such, a detailed description of their physical and chemical state can provide pivotal information regarding such Processes. By constraining the GSD of volcanic deposits one can thereby deliver powerful constraints on the energetics and dynamics of eruptions. In order to do so we must distinguish between two primary controls: 1) fragmentation of magma to tephra, and 2) secondary transport-related Processes (such as abrasion and comminution), within the conduit and until deposition of the particles. Variations in particle interactions in the conduit together with conduit geometry, may be major factors in modifying the GSD. As in all physicochemical Processes, for eruptive dynamics an experimental basis is an essential element of calibration and quantification. Here, we have conducted the first experimental investigation linking fragmentation and ash production via the influence of 1) particle-componentry and particle-Size, and 2) the conduit geometry (constricted versus unconstricted) on the GSD. Rapid decompression experiments with loose tephra material from the fall deposit of Pomici Principali eruption (10.3 ka, Campi Flegrei) have been conducted in an optically transparent setup that enables the optical monitoring of particle dynamics with a high-speed camera. The samples employed can be classified into two main groups; 1) pumices, and 2) dense clasts (including crystals, lava clasts and wall rock fragments). Our results indicate that 1) a conduit diameter constriction (simulating obstacles in the conduit walls) is likely to reduce the average diameter of individual clasts and increase the generation of ash (