The Experts below are selected from a list of 267 Experts worldwide ranked by ideXlab platform

Taekyoung Ki - One of the best experts on this subject based on the ideXlab platform.

  • Effect of pulse tube volume on dynamics of linear compressor and cooling performance in Stirling-type pulse tube refrigerator
    Cryogenics, 2020
    Co-Authors: Junseok Ko, Sangkwon Jeong, Taekyoung Ki
    Abstract:

    In a Stirling-type pulse tube refrigerator (PTR), the pulse tube volume affects the dynamic behavior of a linear compressor as well as the cooling performance of PTR. In this study, PTRs which have different pulse tube volume are tested and simulated. The simulation code is verified with the experimental measurement of piston displacement, pressure wave, Input Power and cooling capacity. And then, the Power transfer from the Electric Power Input to the cooling capacity is explained with the simulation results. The smaller pulse tube increases the resonant frequency of a linear compressor and suppresses the piston motion because it imposes larger gas spring effect and also larger gas damping effect to the piston. The smaller one allows larger Power transfer from Electric Power to expansion PV work despite the smaller piston displacement, but shows less cooling capacity due to larger thermal losses.

  • Effect of pulse tube volume on dynamics of linear compressor and cooling performance in Stirling-type pulse tube refrigerator
    Cryogenics, 2010
    Co-Authors: Junseok Ko, Sangkwon Jeong, Taekyoung Ki
    Abstract:

    In a Stirling-type pulse tube refrigerator (PTR), the pulse tube volume affects the dynamic behavior of a linear compressor as well as the cooling performance of PTR. In this study, PTRs which have different pulse tube volume are tested and simulated. The simulation code is verified with the experimental measurement of piston displacement, pressure wave, Input Power and cooling capacity. And then, the Power transfer from the Electric Power Input to the cooling capacity is explained with the simulation results. The smaller pulse tube increases the resonant frequency of a linear compressor and suppresses the piston motion because it imposes larger gas spring effect and also larger gas damping effect to the piston. The smaller one allows larger Power transfer from Electric Power to expansion PV work despite the smaller piston displacement, but shows less cooling capacity due to larger thermal losses. ?? 2009 Elsevier Ltd. All rights reserved.

Stefan Seelecke - One of the best experts on this subject based on the ideXlab platform.

  • Modeling and experimental characterization of the stress, strain, and resistance of shape memory alloy actuator wires with controlled Power Input:
    Journal of Intelligent Material Systems and Structures, 2012
    Co-Authors: Stephen J. Furst, Stefan Seelecke
    Abstract:

    Recently, a novel Power controller has been presented that simultaneously controls Electric Power Input and measures resistance of a commercially available Flexinol shape memory alloy wire. This work exploits the new Power controller by plotting shape memory alloy stress, strain, and resistance versus Joule heating Power instead of Input voltage or current. Heating Power is directly related to shape memory alloy temperature, whereas standard constant voltage or constant current Inputs cause more or less heating as the resistance of the wire changes due to phase transformation. A simple experimental setup consisting of a 50-µm-diameter Flexinol wire mounted in series with the tip of a compliant cantilever beam is used to systematically study the shape memory alloy behavior. Actuator performance is reported for a range of prestress values and actuation frequencies. All the experimental data are compared with simulated behavior that is derived from a free energy–based numerical model for shape memory alloy m...

  • Modeling and experimental characterization of the stress, strain, and resistance of shape memory alloy actuator wires with controlled Power Input
    Journal of Intelligent Material Systems and Structures, 2012
    Co-Authors: Stephen J. Furst, Stefan Seelecke
    Abstract:

    Recently, a novel Power controller has been presented that simultaneously controls Electric Power Input and measures resistance of a commercially available Flexinol shape memory alloy wire. This work exploits the new Power controller by plotting shape memory alloy stress, strain, and resistance versus Joule heating Power instead of Input voltage or current. Heating Power is directly related to shape memory alloy temperature, whereas standard constant voltage or constant current Inputs cause more or less heating as the resistance of the wire changes due to phase transformation. A simple experimental setup consisting of a 50-μm-diameter Flexinol wire mounted in series with the tip of a compliant cantilever beam is used to systematically study the shape memory alloy behavior. Actuator performance is reported for a range of prestress values and actuation frequencies. All the experimental data are compared with simulated behavior that is derived from a free energy-based numerical model for shape memory alloy material. Additionally, a new resistance model based on the simulated wire temperature and phase fractions is introduced and compared to experimental data. Exploiting a multifunctional Power controller and an improved understanding of the resistance change during phase transformation will help enable the use of shape memory alloy wires in simultaneous sensing and actuating applications. ©The Author(s) 2012.

Junseok Ko - One of the best experts on this subject based on the ideXlab platform.

  • Effect of pulse tube volume on dynamics of linear compressor and cooling performance in Stirling-type pulse tube refrigerator
    Cryogenics, 2020
    Co-Authors: Junseok Ko, Sangkwon Jeong, Taekyoung Ki
    Abstract:

    In a Stirling-type pulse tube refrigerator (PTR), the pulse tube volume affects the dynamic behavior of a linear compressor as well as the cooling performance of PTR. In this study, PTRs which have different pulse tube volume are tested and simulated. The simulation code is verified with the experimental measurement of piston displacement, pressure wave, Input Power and cooling capacity. And then, the Power transfer from the Electric Power Input to the cooling capacity is explained with the simulation results. The smaller pulse tube increases the resonant frequency of a linear compressor and suppresses the piston motion because it imposes larger gas spring effect and also larger gas damping effect to the piston. The smaller one allows larger Power transfer from Electric Power to expansion PV work despite the smaller piston displacement, but shows less cooling capacity due to larger thermal losses.

  • Effect of pulse tube volume on dynamics of linear compressor and cooling performance in Stirling-type pulse tube refrigerator
    Cryogenics, 2010
    Co-Authors: Junseok Ko, Sangkwon Jeong, Taekyoung Ki
    Abstract:

    In a Stirling-type pulse tube refrigerator (PTR), the pulse tube volume affects the dynamic behavior of a linear compressor as well as the cooling performance of PTR. In this study, PTRs which have different pulse tube volume are tested and simulated. The simulation code is verified with the experimental measurement of piston displacement, pressure wave, Input Power and cooling capacity. And then, the Power transfer from the Electric Power Input to the cooling capacity is explained with the simulation results. The smaller pulse tube increases the resonant frequency of a linear compressor and suppresses the piston motion because it imposes larger gas spring effect and also larger gas damping effect to the piston. The smaller one allows larger Power transfer from Electric Power to expansion PV work despite the smaller piston displacement, but shows less cooling capacity due to larger thermal losses. ?? 2009 Elsevier Ltd. All rights reserved.

Stephen J. Furst - One of the best experts on this subject based on the ideXlab platform.

  • Modeling and experimental characterization of the stress, strain, and resistance of shape memory alloy actuator wires with controlled Power Input:
    Journal of Intelligent Material Systems and Structures, 2012
    Co-Authors: Stephen J. Furst, Stefan Seelecke
    Abstract:

    Recently, a novel Power controller has been presented that simultaneously controls Electric Power Input and measures resistance of a commercially available Flexinol shape memory alloy wire. This work exploits the new Power controller by plotting shape memory alloy stress, strain, and resistance versus Joule heating Power instead of Input voltage or current. Heating Power is directly related to shape memory alloy temperature, whereas standard constant voltage or constant current Inputs cause more or less heating as the resistance of the wire changes due to phase transformation. A simple experimental setup consisting of a 50-µm-diameter Flexinol wire mounted in series with the tip of a compliant cantilever beam is used to systematically study the shape memory alloy behavior. Actuator performance is reported for a range of prestress values and actuation frequencies. All the experimental data are compared with simulated behavior that is derived from a free energy–based numerical model for shape memory alloy m...

  • Modeling and experimental characterization of the stress, strain, and resistance of shape memory alloy actuator wires with controlled Power Input
    Journal of Intelligent Material Systems and Structures, 2012
    Co-Authors: Stephen J. Furst, Stefan Seelecke
    Abstract:

    Recently, a novel Power controller has been presented that simultaneously controls Electric Power Input and measures resistance of a commercially available Flexinol shape memory alloy wire. This work exploits the new Power controller by plotting shape memory alloy stress, strain, and resistance versus Joule heating Power instead of Input voltage or current. Heating Power is directly related to shape memory alloy temperature, whereas standard constant voltage or constant current Inputs cause more or less heating as the resistance of the wire changes due to phase transformation. A simple experimental setup consisting of a 50-μm-diameter Flexinol wire mounted in series with the tip of a compliant cantilever beam is used to systematically study the shape memory alloy behavior. Actuator performance is reported for a range of prestress values and actuation frequencies. All the experimental data are compared with simulated behavior that is derived from a free energy-based numerical model for shape memory alloy material. Additionally, a new resistance model based on the simulated wire temperature and phase fractions is introduced and compared to experimental data. Exploiting a multifunctional Power controller and an improved understanding of the resistance change during phase transformation will help enable the use of shape memory alloy wires in simultaneous sensing and actuating applications. ©The Author(s) 2012.

Sangkwon Jeong - One of the best experts on this subject based on the ideXlab platform.

  • Effect of pulse tube volume on dynamics of linear compressor and cooling performance in Stirling-type pulse tube refrigerator
    Cryogenics, 2020
    Co-Authors: Junseok Ko, Sangkwon Jeong, Taekyoung Ki
    Abstract:

    In a Stirling-type pulse tube refrigerator (PTR), the pulse tube volume affects the dynamic behavior of a linear compressor as well as the cooling performance of PTR. In this study, PTRs which have different pulse tube volume are tested and simulated. The simulation code is verified with the experimental measurement of piston displacement, pressure wave, Input Power and cooling capacity. And then, the Power transfer from the Electric Power Input to the cooling capacity is explained with the simulation results. The smaller pulse tube increases the resonant frequency of a linear compressor and suppresses the piston motion because it imposes larger gas spring effect and also larger gas damping effect to the piston. The smaller one allows larger Power transfer from Electric Power to expansion PV work despite the smaller piston displacement, but shows less cooling capacity due to larger thermal losses.

  • Effect of pulse tube volume on dynamics of linear compressor and cooling performance in Stirling-type pulse tube refrigerator
    Cryogenics, 2010
    Co-Authors: Junseok Ko, Sangkwon Jeong, Taekyoung Ki
    Abstract:

    In a Stirling-type pulse tube refrigerator (PTR), the pulse tube volume affects the dynamic behavior of a linear compressor as well as the cooling performance of PTR. In this study, PTRs which have different pulse tube volume are tested and simulated. The simulation code is verified with the experimental measurement of piston displacement, pressure wave, Input Power and cooling capacity. And then, the Power transfer from the Electric Power Input to the cooling capacity is explained with the simulation results. The smaller pulse tube increases the resonant frequency of a linear compressor and suppresses the piston motion because it imposes larger gas spring effect and also larger gas damping effect to the piston. The smaller one allows larger Power transfer from Electric Power to expansion PV work despite the smaller piston displacement, but shows less cooling capacity due to larger thermal losses. ?? 2009 Elsevier Ltd. All rights reserved.