Dr Sören Ehlers

Sören Ehlers graduated as a Master of Science in Mechanical Engineering from the University of Rostock in 2004 and from the Helsinki University of Technology in 2009 as a Doctor of Science with distinction in the field of naval architecture. Prior to his current position at NTNU, he worked as a post-doc researcher at the Department of Applied Mechanics (Marine Technology) at the Aalto University.

Since 2004, Sören Ehlers is teaching international intensive courses at universities as well as master level ship design courses at the Aalto University, and instructs doctoral researchers. He is an expert in consequences assessment for accidental events, such as collision or grounding, and further in the field of material modelling for non-linear finite element simulations. Furthermore, he is contributing to the development of new ice material models to assess the ice-structure interaction. Thus he is concerned with the overall risk assessment of ships subjected to accidental events. Furthermore, he combines optimization techniques with extensive assessment procedures to obtain new structural concepts.

Sören Ehlers has more than 50 publications in the field of naval architecture and structural analysis. He is a member of the international ship structures committee (ISSC), the international Stability R&D Committee (STAB), the German society of Naval Architects (STG), the PIANC working group 151 and he acts as a reviewer for several international journals. Furthermore, he led the organization of the international conference for collision and grounding of ships in 2010 and encourages young researchers in the field to cooperate through different working groups. Since 2004, he is involved in numerous international and national projects and acted as a project manager. In 2003, he co-founded the research and consultancy company AS2CON.

"I am very pleased to be part of the Arctic developments through NTNU as part of this knowledge hub. With a background in accidental structural analysis and related risk assessment, optimization and conceptual design as well as material modelling for steel and ice, I am able to contribute to new and innovative transport systems for the Arctic Sea. Therefore, I will develop a holistic design environment for ships operating in Arctic conditions and thereby assess the vessels´ performance and strength operating in ice, which can further be used to assess and minimize the operational risk. In order to achieve this, I will develop my expertise in the field of ship optimization techniques for the arctic region to gain a rational insight into the phenomena involved and assess their influence on the environment and global cost. Additionally, I will synthesis the disciplines found at NTNU and worldwide in the Arctic Technology field within this design environment. Thereby, a global competitiveness in the Arctic transport sector through state of the art research findings can be secured."

Basic research

o   Fluid-Ice-Water-Structure Interaction suitable for optimization

o   Assessment of the material behaviour

o   Development of new materials and structures

o   Development of methods to assess the environmental impact and cost of new transport systems for the Arctic Sea

Applied research

o   Design methods for Arctic Sea transport systems

o   Development of sustainable and competitive concepts

o   Innovative solutions for operations in darkness and remoteness

o   Development of active and passive safety features for reducing the hazard-related risks

o   Integration of the Arctic and non-Arctic passages as a part of a global fleet- and supply chain management system

o   Development of design requirements to fulfil the demands for the northern passages in the future

Within both research areas I would like to develop a close industrial cooperation to support innovative products with state of the art research results. Additionally, direct feedback from industrial partners working in the Arctic Sea region will be highly appreciated to strengthen the overall competitiveness through innovative strategies and designs.

Reference list (the ten most relevant and recent publications)

  • Von Bock und Polach R, Ehlers S. Heave and pitch motions of a ship in model ice: an experimental study on ship resistance and ice breaking pattern. Cold Regions Science and Technology, 2011; 68; 49-59.
  • Ehlers S, Remes H, Klanac A, Naar H. A multi-objective optimisation-based structural design procedure for the concept stage - a chemical product tanker case study. Ship Technology Research, Schiffstechnik, 2010; 57(3): 182-197.
  • Rigo P, ?ani? V, Ehlers S, Andri? J. Design of Innovative Ship Concepts using an Integrated Decision Support System for Ship Production and Operation. Brodogradnja-Shipbuilding 2010; 61(4): 367-381.
  • Ehlers S, Tabri K, Romanoff J, Varsta P. Numerical and Experimental Investigation on the Collision Resistance of the X-core Structure. Journal of Ships and Offshore Structures, Special Issue on Collision and Grounding, 2010; 1–9.
  • Ehlers S. A procedure to assess the damage of a grounded ship: a full-scale validation case study. Ship Technology Research, 2010; 57(1); 50-64
  • Ehlers S. The influence of the material relation on the accuracy of collision simulations. Marine Structures, 2010; 23; 462-474.
  • Kõrgesaar M, Ehlers S. An Assessment Procedure of the Crashworthiness of an LNG Tanker Side Structure. Ship Technology Research, Schiffstechnik, 2010; 57(1): 50-64.
  • Ehlers S. A procedure to optimize ship side structures for crashworthiness. Journal of Engineering for the Maritime Environment 2009; 224: 1-12.
  • Ehlers S. Strain and stress relation until fracture for finite element simulations of a thin circular plate. Thin-Walled Structures 2009; 48(1); 1-8.
  • Ehlers S, Varsta P. Strain and stress relation for non-linear finite element simulations. Thin-Walled Structures 2009; 47; 1203-1217.