News Stories

  • November

    A Measurement System for the Study of Nonlinear Propagation Through Arrays of Scatterers

    Abstract: Various experimental challenges exist in measuring the spatial and temporal field of a nonlinear acoustic pulse propagating through an array of scatterers. Probe interference and undesirable high-frequency response plague typical approaches with acoustic microphones, which are also limited to resolving the pressure field at a single position. Measurements made with optical methods do not have such drawbacks, and schlieren measurements are particularly well suited to measuring both the spatial and temporal evolution of nonlinear pulse propagation in an array of scatterers. Herein, a measurement system is described based on a z-type schlieren setup, which is suitable for measuring axisymmetric phenomena and visualizing weak shock propagation. In order to reduce directivity and initiate nearly spherically-symmetric propagation, laser induced breakdown serves as the source for the nonlinear pulse. A key component of the schlieren system is a standard schliere, which allows quantitative schlieren measurements to be performed. Sizing of the standard schliere is aided by generating estimates of the expected light refraction from the nonlinear pulse, by way of the forward Abel transform. Finally, considerations for experimental sequencing, image capture, and a reconfigurable rod array designed to minimize spurious wave interactions are specified.
  • Army Installations of the Future Industry Day 2019: Summary Report

    Abstract: The Army Installations of the Future Industry Day was held on 23 May 2019 at the Renaissance Capital View hotel in Arlington, VA to identify the availability and maturity of specific commercial off-the-shelf (COTS) “smart installation” capabilities, technologies, and products; and to seek interest from industry in exploring potential approaches, requirements, standards, and/or specifications for pilot demonstrations at Army installations focused on 10 use-case technology areas. The Industry Day event included approximately 336 participants comprised of Academia (5), Industry (226), and Government (105). This report presents “road maps” that outline the Army’s desired outcomes for the target technology areas and potential pilot technology demonstrations.
  • Numerical Analysis of Weak Acoustic Shocks in Aperiodic Array of Rigid Scatterers

    Abstract: Nonlinear propagation of shock waves through periodic structures have the potential to exhibit interesting phenomena. Frequency content of the shock that lies within a bandgap of the periodic structure is strongly attenuated, but nonlinear frequency-frequency interactions pumps energy back into those bands. To investigate the relative importance of these propagation phenomena, numerical experiments using the Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation are carried out. Two-dimensional propagation through a periodic array of rectangular waveguides is performed by iteratively using the output of one waveguide as the input for the next waveguide. Comparison of the evolution of the initial shock wave for both the linear and nonlinear cases is presented.
  • ERDC researcher uses lessons learned from historic pandemics to address COVID

    COVID-19 proved to be unexpected to many people in the world, but Dr. Igor Linkov, Risk and Decision Science (RaDS) Team lead at the U.S. Army Engineer Research and Development Center’s Environmental Laboratory, found himself on familiar ground.
  • USACE Vicksburg District to use new payment system for fee collection at Lake Ouachita campground

    VICKSBURG, Miss. – The U.S. Army Corps of Engineers (USACE) Vicksburg District will use a new electronic payment system for fee collection at Twin Creek Campground beginning Dec. 1.
  • Hunter Ethics

    CARLYLE LAKE - With the fall hunting season underway, hunters are reminded of their obligation to practice ethical and safe hunting while in the field. Remember, your personal ethics might not match your neighbors, but certain guidelines do pertain to all hunters.
  • TAM Awards Task Order for Saudi Arabia forces

    The U.S. Army Corps of Engineers Middle East District awarded a task order for AE services for the Royal Saudi Land Forces Aviation Command (RSLFAC) Master Planning and Construction Phase 2A Facilities and Infrastructure in the Kingdom of Saudi Arabia.
  • The Dredge Merritt: Maintenance and Repairs

    The dredge Merritt is finally back in the water at the North Carolina State Shipyard after routine maintenance. For the past month the crew has been busy replacing and updating steering systems, painting, replacing gear, cleaning fuel tanks, and repairing corrosion. This period of repairs has been very successful and beneficial to the vessel.
  • CERL hosts senior Army installation, energy, environment leadership

    Leadership from the U.S. Army Engineer Research and Development Center (ERDC), Construction Engineering Research Laboratory (CERL) discussed ongoing projects and innovative technologies with the Principal Deputy Assistant Secretary of the Army (PDASA) for Installations, Energy and Environment (IE&E) Bryan Gossage, during his visit to the CERL campus Oct. 30.
  • Kansas City District delivers $740 million program for the Heartland

    As the U.S. Army Corps of Engineers, Kansas City District wrapped up final contract awards for fiscal year 2020, the team wants to share a summary of a few major accomplishments and how they tie into the district mission and benefit the Heartland region. The district awarded 1575 contracts worth $740.1 million in fiscal year 2020 – ending September 30.

News Releases

  • A Measurement System for the Study of Nonlinear Propagation Through Arrays of Scatterers

    Abstract: Various experimental challenges exist in measuring the spatial and temporal field of a nonlinear acoustic pulse propagating through an array of scatterers. Probe interference and undesirable high-frequency response plague typical approaches with acoustic microphones, which are also limited to resolving the pressure field at a single position. Measurements made with optical methods do not have such drawbacks, and schlieren measurements are particularly well suited to measuring both the spatial and temporal evolution of nonlinear pulse propagation in an array of scatterers. Herein, a measurement system is described based on a z-type schlieren setup, which is suitable for measuring axisymmetric phenomena and visualizing weak shock propagation. In order to reduce directivity and initiate nearly spherically-symmetric propagation, laser induced breakdown serves as the source for the nonlinear pulse. A key component of the schlieren system is a standard schliere, which allows quantitative schlieren measurements to be performed. Sizing of the standard schliere is aided by generating estimates of the expected light refraction from the nonlinear pulse, by way of the forward Abel transform. Finally, considerations for experimental sequencing, image capture, and a reconfigurable rod array designed to minimize spurious wave interactions are specified.
  • Army Installations of the Future Industry Day 2019: Summary Report

    Abstract: The Army Installations of the Future Industry Day was held on 23 May 2019 at the Renaissance Capital View hotel in Arlington, VA to identify the availability and maturity of specific commercial off-the-shelf (COTS) “smart installation” capabilities, technologies, and products; and to seek interest from industry in exploring potential approaches, requirements, standards, and/or specifications for pilot demonstrations at Army installations focused on 10 use-case technology areas. The Industry Day event included approximately 336 participants comprised of Academia (5), Industry (226), and Government (105). This report presents “road maps” that outline the Army’s desired outcomes for the target technology areas and potential pilot technology demonstrations.
  • Numerical Analysis of Weak Acoustic Shocks in Aperiodic Array of Rigid Scatterers

    Abstract: Nonlinear propagation of shock waves through periodic structures have the potential to exhibit interesting phenomena. Frequency content of the shock that lies within a bandgap of the periodic structure is strongly attenuated, but nonlinear frequency-frequency interactions pumps energy back into those bands. To investigate the relative importance of these propagation phenomena, numerical experiments using the Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation are carried out. Two-dimensional propagation through a periodic array of rectangular waveguides is performed by iteratively using the output of one waveguide as the input for the next waveguide. Comparison of the evolution of the initial shock wave for both the linear and nonlinear cases is presented.
  • ERDC researcher uses lessons learned from historic pandemics to address COVID

    COVID-19 proved to be unexpected to many people in the world, but Dr. Igor Linkov, Risk and Decision Science (RaDS) Team lead at the U.S. Army Engineer Research and Development Center’s Environmental Laboratory, found himself on familiar ground.
  • USACE Vicksburg District to use new payment system for fee collection at Lake Ouachita campground

    VICKSBURG, Miss. – The U.S. Army Corps of Engineers (USACE) Vicksburg District will use a new electronic payment system for fee collection at Twin Creek Campground beginning Dec. 1.
  • Hunter Ethics

    CARLYLE LAKE - With the fall hunting season underway, hunters are reminded of their obligation to practice ethical and safe hunting while in the field. Remember, your personal ethics might not match your neighbors, but certain guidelines do pertain to all hunters.
  • TAM Awards Task Order for Saudi Arabia forces

    The U.S. Army Corps of Engineers Middle East District awarded a task order for AE services for the Royal Saudi Land Forces Aviation Command (RSLFAC) Master Planning and Construction Phase 2A Facilities and Infrastructure in the Kingdom of Saudi Arabia.
  • The Dredge Merritt: Maintenance and Repairs

    The dredge Merritt is finally back in the water at the North Carolina State Shipyard after routine maintenance. For the past month the crew has been busy replacing and updating steering systems, painting, replacing gear, cleaning fuel tanks, and repairing corrosion. This period of repairs has been very successful and beneficial to the vessel.
  • CERL hosts senior Army installation, energy, environment leadership

    Leadership from the U.S. Army Engineer Research and Development Center (ERDC), Construction Engineering Research Laboratory (CERL) discussed ongoing projects and innovative technologies with the Principal Deputy Assistant Secretary of the Army (PDASA) for Installations, Energy and Environment (IE&E) Bryan Gossage, during his visit to the CERL campus Oct. 30.
  • Kansas City District delivers $740 million program for the Heartland

    As the U.S. Army Corps of Engineers, Kansas City District wrapped up final contract awards for fiscal year 2020, the team wants to share a summary of a few major accomplishments and how they tie into the district mission and benefit the Heartland region. The district awarded 1575 contracts worth $740.1 million in fiscal year 2020 – ending September 30.

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