Improved methods of determining temperature transients in reactor systems are desired because of recent interest in Pressurized Thermal Shock (PTS) issues. The research presented herein was performed in support of the Nuclear Regulatory Commission's effort to re-evaluate its existing PTS rules. These rules are particularly important to the re-licensing of...
Non-destructive testing is a methodology to inspect production and operational parts for potential flaws, defects, or damages. The present work is based on pulsed wave thermography, a thermal imaging method based on heat conduction to identify surface and subsurface defects potentially present in a component. Pulsed wave thermography applies a...
An important element in rector safety and fuel performance assessments is the efficient calculation of the time dependent temperature profiles within reactor fuel pins. Because the fuel pins have temperature dependent thermal properties, the governing partial differential equations are nonlinear. Traditionally, finite difference or finite element methods have been used...
In the present work, a correlation is made between seismic intensity parameters and total damage indicators of reinforced concrete structures. For this purpose, natural ground motions recordings were used, from which intensity measures were calculated and alternatives were proposed. Then, through dynamic inelastic time history analyzes, damage indices were evaluated...
When large disturbances occur in interconnected power systems, there exists the danger
that the power system states may leave an associated region of stability, if timely corrective action
is not taken. Open-loop remedial control actions such as field-forcing, line-tripping, switching of
series-capacitors, energizing braking resistors, etc., are helpful in reducing...
Calls for reform within engineering education frequently cite the need to better prepare the future workforce for the imminent challenges that they will face. The focus in preparing students for the workforce is often on the educational system and not on understanding the actual workplace. But if we are to...
Amorphous multicomponent metals have promising applications in novel electronic devices because of their atomically smooth surface morphology and lack of grain boundaries. It is important to understand the thermal transport properties of amorphous metals and an accurate measurement of their thermal conductivity will be essential for further improvement of device...
The defect mechanisms that underpin the high energy density dielectric 0.8BaTiO₃–0.2Bi(Zn₁/₂Ti₁/₂) O₃
were investigated. Characterization of the nominally stoichiometric composition revealed the
presence of a Ti³⁺-related defect center, which is correlated with lower resistivities and an
electrically heterogeneous microstructure. In compositions with 2 mol. % Ba-deficiency, a barium
vacancy-oxygen vacancy...
Full Text:
Science, School of Mechanical, Industrial, and Manufacturing Engineering,
Oregon State University
A numerical model has been developed to simulate the firing of an inkjet printhead.
The model evaluates the heat generation and diffusion within the thin film structure, the
phase change and vapor bubble growth in the ink, and the subsequent flow of ink from the
orifice. The heat transfer is...