Three DTU researchers will defend their doctoral theses this autumn.
The three theses deal with very different topics such as calculations of the forces to which a wind turbine is exposed, omega-3 fatty acids from sea level to the deep ocean, and an electrochemical approach to catalytic reactions. However, they do have one thing in common: They have given the researchers an opportunity to review many years of work and find new perspectives.
Below are the three doctorates. Photos by Joachim Rode.
Associate Professor Irina Petrushina, DTU Energy
Title: Electrochemistry as a tool for Study, Development and Promotion of Catalytic Reactions.
What: The strong connection between chemical and electrochemical reactions can be used to find optimal parameters much faster than by changing parameters such as temperatures and concentrations. The thesis describes how very small electrical charges can accelerate a catalytic process. Finally, the thesis is a breakthrough in electrolysis, where, for example, in hydrogen filling stations you can replace the use of precious metals such as platinum and iridium.
When: Doctoral defence at 2 p.m. on 2 November in Building 101, Meeting Room 1.
Senior Researcher Sigrún Huld Jónasdóttir, DTU Aqua
Titel: "A journey from light into darkness - Fatty acids in the marine ecosystem: From photosynthesis to copepod lipids and sequestration".
Hvad: Vandlopper er den vigtigste transportmekanisme af omega-3 fedtsyrer igennem havets fødenet. Hvert efterår vandrer trillioner af vandlopper med store mængder voks-estere fra overfladen til store dybder, hvor de går i dvale. Voks-esterne nedbrydes under vandloppernes vinterdvale, og danner CO₂. Mængden af efterladt kulstof fra vandlopperne udgør et stort ”CO₂-fodaftryk,” som har stor betydning for havets kredsløb.
Hvornår: Forsvarer den 13. november kl. 14 i bygning 101, mødelokale 1.
Professor Jens Nørkær Sørensen, DTU Wind Energy
Title: General Momentum Theory for Horizontal Axis Wind Turbines (the doctorate has been published by Springer as a textbook under the same title).
Subject: To pinpoint wind turbine performance and the stresses to which they are exposed, you use momentum theory with a number of simplifications. The thesis reviews these theories as there are numerous examples of misinterpretations and incorrect statements based on the theory. Computer Fluid Dynamics (CFD) calculations have shown errors in the calculations of centrifugal effects in the turbine’s rotor. Jens Nørkær Sørensen proposes new ideas for developing the theory and to increase accuracy.
When: Doctoral defence at 2 p.m. on 11 December in Building 101, Meeting Room 1.