Tidligere arrangementer - Side 127

Simulations of Fluid-Solid interactions (FSI) are becoming more common as faster computers enables the study of larger models including both fluids and solids. In many applications it is of significant importance to determine the impact that a flowing fluid has on the mechanical structure surrounding it. Vortex-induced vibrations can give structural failure due to fatigue, but it can also produce undesired acoustic noise. During the seminar, several examples of FSI problems and solutions will be demonstrated. The examples include the study of flow induced vibrations in a compressor exhaust, the dynamic flow of oil through a filter, the impact of water waves on a submerged object, etc.

Large-eddy simulations are also advancing in the industrial CFD society. RANS modeling has shown to be insufficient in many complex flow situations, and LES has proven to provide answers to many fundamental questions in turbulent flows. A brief demonstration  of an example with flow over a wing profile is presented. Using LES, it is possible to extract valuable information regarding lift, drag, etc., but it is also possible to visualize the turbulent structures evolving from the boundary layer on the wing.

Love H?kansson is at EDR - Engineering Data Resources

Fredagskollokvium

Arvid Raknerud, Statistisk Sentralbyr?, skal snakke om

Indirect inference methods for stochastic volatility models based on non-Gaussian Ornstein-Uhlenbeck processes

Friday seminar by R. J. Scott McCairns

Fredagskollokvium

Gjesteforelesning ved Professor Steinar Johansen, 澳门葡京手机版app下载sgruppe for RNA og Transkriptomikk, Universitetet i Troms?.

Hans Olav Melberg, Institutt for helseledelse og helse?konomi, Universitetet i Oslo, og SIRUS, skal snakke om

Hvem er den Anonyme forfatteren bak boken Kongepudler?

Fredagskollokvium

CEES Extra Seminar by Jeffrey Hutchings

Ingrid K. Glad, Matematisk Institutt, Universitetet i Oslo, skal snakke om

Local comparison of empirical densities: a challenge from gene therapy

Friday seminar by Nick Kamenos

Fredagskollokvium

Gjesteforelesning ved Dr. Heather Lord.

Konstantinos Fokianos, Department of Mathematics and Statistics, University of Cyprus, skal snakke om

Autoregressive models for count times series

?rets Rosselandforelesning finner sted 5. april i Store fysiske auditorium.

Guest lecture by Executive Director of iBOL (International Barcode of Life), Dr. Peter Freeman.

Fredagskollokvium

Turbulence is complex flow phenomenon with a wide range of scales of motion. Even though there is advancements in measurement technologies, the tools we use in the laboratories are often not adequate to extract all the information necessary for understanding and characterizing this flow. How-wire anemometry has been used by researcher for many decades due to its high temporal resolution. Even though it has good temporal resolution, it can only provide single point data. One also needs to be careful while using hot-wires because it has its own limitations given different flow configurations. In this talk, we will see some examples of hot-wire measurements in shear flow turbulence. Namely we will look at axisymmetric wake, turbulent boundary layers, and wake boundary layer interactions. Each of these measurements requires different setups and different adjustments. We will discuss what we can measure, how we can measure, how we can calibrate and how we should interpret the results.

Murat Tutkun is at the Defense Research Establishment (FFI) and Ecole Centrale de Lille, France

Friday seminar by Vasilis Dakos

Fredagskollokvium

Gabriele Martinelli, Institutt for matematiske fag, NTNU,skal snakke om

Sequential exploration program in spatially-correlated domains

Friday seminar by Per Fauchald

Fredagskollokvium

Recent findings show that moderate mixing levels typical of mid-latitude can erode or even remove the Arctic cold halocline layer and that internal wave induced mixing is enhanced in the absence of sea ice. In a seasonally ice-free Arctic Ocean increased levels of mixing, sufficient to remove the cold halocline layer, can be expected as a result of wind energy input over large areas of open water. The ice is then easily exposed to the relatively warm Atlantic water, possibly leading to a strong positive feedback. I will report on insight gained from field work conducted during the International Polar Year. Detailed finescale and turbulence measurements were made from drifting ice in the central Arctic and in the southern Yermak Plateau located in the Marginal Ice Zone northwest of Svalbard. Observations are analyzed to describe the characteristics of internal waves and turbulent mixing in the Arctic Ocean. The role of diapycnal mixing away from abyssal plains is discussed for the Arctic Ocean and regional heat budget and ice cover.

Ilker Fer is at the Department of Geophysics at UiB