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Brad Merrill

Group Leader for the Fusion Safety Program. Technical lead for computer code development for fusion safety. Work in licensing, fusion safety code development, and modifications for computer codes for the ITER International Project. Experience in modeling multi­phase fluid flow, multi‐phase and radiant heat transfer, aerosol transport, electromagnetics, and superconducting magnets. The fusion safety computer codes he has developed address tritium transport in materials, material oxidation, multi‐phase fluid flow, multi‐phase heat transfer, aerosol resuspension and transport, electrodynamics, radiant energy transport, and magnet arcing. More than 40 years experience in thermal science, safety analysis, and safety code development. Bachelor’s in nuclear engineering from Oregon State University.

208-526-0395Email Contact
Lee Cadwallader

Safety and risk assessment of high technology energy systems. Specializes in component failure data collection and analysis, operating experience data, accident-initiating event data, and system failure event information support for public and worker safety.Performs research in reliability, availability, maintainability, and inspectability (RAMI). Coordinates a task in failure rate data for the IEA implementing agreement on environmental, safety and economic aspects of fusion power. Master’s degrees in nuclear engineering (University of Missouri­Rolla), mechanical engineering (University of Idaho), and industrial safety technology (University of Idaho). Over thirty years of experience at INL.

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Masashi Shimada

Leading Principal Investigator at the Safety and Tritium Applied Research (STAR) facility at INL in support of the DOE Fusion Energy Science tritium and safety research. Principal  Investigator of the Tritium Plasma Experiment (TPE), Tritium Lead Lithium Eutectic (TLLE) experiment, and the Tritium Heat eXchanger experiment (THX). Conducts experiments and numerical modeling of hydrogen isotope permeation, especially tritium, and transport in materials for fusion applications as well as for the DOE Nuclear Energy (NE) Very High Temperature Reactor (VHTR) fission plant design. Serves as the Task 1 (In-Vessel Tritium Source Term) coordinator for the International Energy Agency (IEA) Implementing Agreement on the Environmental, Safety and Economic Aspects of Fusion Power (ESE-FP). PhD in Engineering Physics from the University of California-San Diego. Over seven years of experience at INL.

208-533-4472Email Contact
Paul Humrickhouse

Research Scientist in the Fusion Safety Program. Research areas include fusion systems analysis, thermal hydraulics and heat transfer, severe accident analysis, nuclear aerosols, dust explosions, granular materials, tritium permeation and transport, and beryllium handling and technology. Principal Investigator of the Experimental Chamber for Evaluation of Exploding Dust (ExCEED). INL representative in the IAEACoordinated Research Project (CRP) on Dust in Fusion Devices and the Fusion Energy Systems Studies (FESS)​ group. Coordinator for Task 3 (Activation Products Source Terms) of the IEA Implementing Agreement on the Environmental, Safety, and Economic Aspects of Fusion Power (IEAESEFP). PhD in Nuclear Engineering and Engineering Physics from the University of Wisconsin-Madison. Over five years of experience at INL.

208-526-7496Email Contact
Robert Pawelko

​Scientist in the Fusion Safety Program. Investigates tritium permeation in high temperature alloys. Responsible for tritium accountability measurements and documentation and assists in general laboratory activities at the STAR lab. Knowledgeable in tritium accountancy and tritium measurement systems, quadrupole mass spectrometry, BET surface area measurements, elemental assay by prompt gamma neutron activation analysis, and radiation measurements and spectrometry. Supports tasks in hydrogen isotope transport in fusion relevant material studies, beryllium dust explosion studies, beryllium-steam reactivity studies, tritium recovery from irradiated beryllium research, waste characterization, getter applications, and radiation monitoring systems. B.S. in physics from Northeastern Illinois University. Over 24 years of experience at INL.

208-533-4792Email Contact
Chase Taylor

​Experimental researcher with expertise in hydrogen retention, plasma material interactions, fusion technology, surface chemistry analysis techniques, vacuum systems. Research interests include tritium retention in neutron damaged refractory materials, techniques for measuring defect concentration, and tritium permeation. Principal researcher for STAR surface characterization equipment, including glow discharge optical emission spectroscopy (GD-OES), X-ray photoelectron spectroscopy (XPS), scanning Auger microprobe (SAM), positron annihilation spectroscopy (PAS), and thermal desorption spectroscopy (TDS). Operates the neutron irradiated material ion implantation experiment (NIMIIX) focusing on deuterium ion implantation. Conducts thermal desorption spectroscopy and positron annihilation spectroscopy. PhD in nuclear engineering from Purdue University. Joined INL in 2012.

208-533-4068Email Contact