The impact of MCNP6 depletion resolution on core lifetime is examined in the context of the Snowflake microreactor with explicit TRISO fuel. The change in core lifetime and iso- tope mass as a result of different tracked isotopes, timesteps, and spatial regions is discussed. Calculation speed of a prototype MCNP...
Small hydrocarbon particles such as soot and soot precursors pose a serious threat to human health and Earth's climate. Understanding the mechanisms by which soot particles form and grow is the first step to reducing the prevalence of these particles. Computational simulations are used to investigate combusting systems which are...
Detonation combustion is of great interest for propulsion devices because of its potential to increase thermodynamic efficiency, reduce the weight of current gas turbine engines, and rapidly accelerate to high Mach numbers. Detonation engines might also have the ability to decrease harmful exhaust products from traditional propulsion methods. In order...
Computational fluid dynamics conjugate heat transfer simulations were performed on a packed bed test facility using Dowtherm-A as the working fluid. Multiple test cases were simulated for a Reynolds number range of 188 – 1524 and a set heater power of 60 kW. Temperature profiles were extracted, and the near-wall...
Force data for a flapping foil energy harvester with active leading edge motion operating in the low reduced frequency range is collected to determine how leading edge motion affects energy harvesting performance. The foil pivots about the midchord and operates in the low reduced frequency range of 0.06, 0.08, and...
The aerodynamic performance of an oscillating pitching and plunging foil operating in the energy harvesting mode is investigated. Experiments are conducted in a closed-loop recirculating wind tunnel at Reynolds numbers of 24,000 to 48,000, and reduced frequencies (k = fc/u) of 0.042 to 0.083. Foil kinematics are varied through the...
Engineering applications often require fast, accurate solutions of fluid flow around freely moving bodies. The massive parallelism enabled by graphics processing unit (GPU) architecture enables high performance, offering a promising alternative to traditional solver acceleration via multicore central processing units (CPU). However, fully harnessing GPU parallelism requires specialized algorithms and...
Characterization of a microchannel solar thermal receiver for supercritical carbon dioxide (sCO₂) is presented. The receiver design is based on conjugate computational fluid dynamics and heat transfer simulations as well as thermo-mechanical stress analysis. Two lab scale receivers with a 2x2 cm² absorber area are fabricated and experimentally characterized -...
The number of wind turbines and wind farms in the Pacific Northwest has increased dramatically in the past six years, which represents a significant amount of electrical generation capacity connected to the public electric grid. However, the variable nature of wind sometimes introduces excessive power, or conversely shortages, in power...
In a Modular High Temperature Gas Reactor (MHTGR), the Depressurized Conduction Cooldown (DCC) event can be separated into three distinct stages: 1) depressurization, 2) air ingress and, 3) natural circulation. During normal operations, the HTGR utilizes forced convection to move the helium coolant through the reactor core. Thus, during normal...