Media (Adrian S. Sabau)

• WATE TV reporting on ORNL helping NASA with testing for Space Probe heading towards the Sun, Aug 15, 2018.
• ORNL Movie illustrating contributions to Solar Probe, Aug 15, 2018.
• ORNL story tip on high-heat flux testing for Solar Probe, May 1, 2018.
• ORNL research highlight on high-heat flux testing for Solar Probe, May 11, 2018.
• SERDP webinar on laser-interference structuring, Oct. 19, 2017.
• ORNL story tip on laser-interference for bonding Al-Composites, ORNL Movie illustrating laser-interference for adhesive bonding, May 19, 2016.
• ORNL research highlight on high-heat flux testing of Fields Instrument for Solar Probe September 2, 2015.

Highlights for Representative Results (Adrian S. Sabau)

• Exfoliation analysis in boiler tubes (2007-2013)
  • Developed a comprehensive oxide-growth, stress analysis, and heat transfer model to predict oxide exfoliation in boiler tubes by simulating the stress evolution in oxide layers grown inside steam tubes during boiler shut-downs. This research was sponsored by the Electric Power Research Institute under a Work for Others program (agreement No. EP-P18842/C9306) with the U.S. Department of Energy, Office of Fossil Energy (DOE-FE). The stress-strain variation within a multi-layered oxide scale grown nonisothermally was predicted, leading to the prediction of exfoliation-related events during boiler operation. These finding were in good agreement with plant experience for T22, T91 and TP347H steels.
  
  
• High-heat Flux testing of neutron-irradiated materials for fusion (2012-2018)
  • ORNL Successfully Upgraded the High-Heat Flux Test Capability of the Plasma-Arc Lamp Facility (Nov. 2017). A new reflector was designed and fabricated to increase the maximum source heat-flux from 2.4 to 11 MW/m2.
  • Researchers at ORNL have recently demonstrated the first high heat flux testing of radioactive, neutron-irradiated tungsten on Aug. 15, 2013. A test facility based on plasma-arc lamps was developed at ORNL for high-heat flux testing of neutron-irradiated specimens.
  
  
• Analysis of Fuel Change Effects in Land-based Turbines (2005-2013)
  • Many features of a land based turbine system were considered, including the blade cooling from an open-loop system and the temperature-dependent properties of the working fluids. The ratio between coolant flows was found to be highest for the first vane. Approximately three times more coolant would be required for the first vane in the SG case than that for the NG case (2006). For the SG case, the components in the last stage experienced higher inner wall temperatures than those for the NG case. This finding is in good agreement with plant experience.
  
  
• Analysis of Infrared Processing (IR) using a plasma arc lamp (2002-2011)
  • A computer model was developed for the numerical simulation of IR processing of powder compact materials. Specific models were developed for the evolution of surface condition and sintering effects during IR processing. Numerical simulations were used to determine IR processing parameters for powder compact materials, 2002-2004.
  • The IR computer model was updated for Pulse Thermal Processing (PTP) using the plasma arc lamp of ultrathin, semitransparent films. Spectral properties of the plasma arc lamp and optical properties of the thin films and substrates were considered. Numerical simulations were used to determine IR processing parameters for PTP of 150 nanometer-thick FePt nanoparticle coating on a silicon wafer, 2004-2005.
  
  
• Thermophysical property measurement (2002-2004)
  • The temperature lags limit the quality and utility of differential scanning calorimetry (DSC) and dilatometer instruments for thermophysical property measurement. New sample holder designs and computational methodologies drastically reduced the temperature lags during DSC and dilotometer measurements, 2004.
  
  
• Investment casting project on tooling dimensions (1999-2008)
  • Mpeg simulation movie: Wax deformation during dwell time using the viscoelastic properties of the wax, 2001
  • The viscoelastic properties of unfilled and filled waxes were measured, 2004
  • Successfull measurement of shell mold temperature and validation of thermal model, 2004
  • The alloy deformation module was validated against experimental results (2005). The amount of shrinkage was correctly predicted for the restrained and unrestrained dimensions of an aluminum alloy A356 casting part.
  
  
• Microporosity prediction in aluminum alloy castings (1997-1999)
  • An algorithm for microporosity prediction was validated against experimental results. A new concept for the growth of shrinkage microporosity was proposed for interdendritic microporosity based on a cavitation-onset threshold for the interdendritic pressure during casting solidification.
  
  
• Free-surface flows: Example of broken-dam flow over a containment dike (1995-1996)
  • Problem setting and experimental results (Greenspan and Young, 1978).
  • Volume of Fluid with improved Boundary Conditions (VOFBC)
    (Code developed from RIPPLE)
  • Solution with the original RIPPLE
  
  
• Numerical Analysis: Example of high-order spatial discretization (1993-1994)
  • Numerical oscillations appear at the interface between the uniform and nonuniform grid regions even though the boundary layer is properly resolved. Spurious numerical oscillations are eliminated.
  • Computational efficiency of compact fourth-order solution algorithm is increased ten times over that of second-order one.