Sökning: "Gravity waves"

Visar resultat 1 - 5 av 36 avhandlingar innehållade orden Gravity waves.

1. 1. Was Einstein Wrong? : Theoretical and observational constraints on massive gravity

   Författare :Marcus Högås; Edvard Mörtsell; David Mota; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Gravity; Massive gravity; Bimetric gravity; Cosmology; Gravitational collapse; Gravitational waves; Observational constraints; Theoretical Physics; teoretisk fysik;

   Sammanfattning : For more than a century, Einstein's theory of general relativity has described gravitational phenomena with astonishing precision. However, for the theory to fit observations we need to add two elusive substances: dark energy and dark matter. Together they add up to 95% of the energy budget of the Universe. LÄS MER

3. 2. Steady waves in local and nonlocal models for water waves

   Författare :Tien Truong; Matematik (naturvetenskapliga fakulteten); []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; The steady Euler equations; the Whitham equation; solitary waves; highest waves; periodic waves; transverse dynamics; The steady Euler equations; the Whitham equation; solitary waves; highest waves; periodic waves; transverse dynamics;

   Sammanfattning : We study the steady Euler equations for inviscid, incompressible, and irrotational water waves of constant density. The thesis consists of three papers. The first paper approaches the Euler equations through a famous nonlocal model equation for gravity waves, namely the Whitham equation. LÄS MER

4. 3. Introducing Surface Gravity Waves into Earth System Models

   Författare :Lichuan Wu; Anna Rutgersson; Erik Sahlée; Peter Janssen; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Surface gravity waves; Air-sea interaction; Earth-System Model; Atmospheric mixing; Upper-ocean turbulence; Meteorology; Meteorologi;

   Sammanfattning : Surface gravity waves alter the turbulence of the bottom atmosphere and the upper ocean. Accordingly, they can affect momentum flux, heat fluxes, gas exchange and atmospheric mixing. However, in most state-of-the-art Earth System Models (ESMs), surface wave influences are not fully considered or even included. LÄS MER

5. 4. Waves and instabilities through the lens of asymptotic analysis

   Författare :Anthony Bonfils; John Wettlaufer; Dhrubaditya Mitra; Woosok Moon; Jerome Neufeld; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; waves; wrinkles; instabilities; Theoretical Physics; teoretisk fysik;

   Sammanfattning : Understanding the interaction of water waves with winds and marine currents is a fundamental problem in geophysical fluid dynamics. From the point of view of hydrodynamic stability, surface waves are regarded as perturbations of an inviscid parallel shear flow modeling the wind in the air and the current in the water. LÄS MER

7. 5. Wave Loads and Peak Forces on Moored Wave Energy Devices in Tsunamis and Extreme Waves

   Författare :Linnea Sjökvist; Malin Göteman; Mats Leijon; Peter Stansby; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; OpenFOAM; CFD; Wave power; Tsunami waves; Extreme waves; Offshore; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

   Sammanfattning : Surface gravity waves carry enormous amounts of energy over our oceans, and if their energy could be harvested to generate electricity, it could make a significant contribution to the worlds power demand. But the survivability of wave energy devices in harsh operating conditions has proven challenging, and for wave energy to be a possibility, peak forces during storms and extreme waves must be studied and the devices behaviour understood. LÄS MER