Rotating heat pipe with Dowtherm A for intermediate temperature applications in a heat pipe assisted annealing process: An experimental study on internal heat transfer with attention for the effects of non-condensable gas described by a computational model

The production of steel is an energy intensive process, using 20GJ/tonne of steel. The energy use needs to be declined by 10% in 2030 in order to be on track of the Sustainable Development Scenario(SDS). About 1GJ/tonne is required today by the annealing process, a heat treatment in which the steel strip is heated to a temperature of about 600...

DNS of heat transfer in a turbulent channel flow over fractal roughness

Convective heat transfer finds applications in several domains of industry like heat exchangers, gas turbine blades, IC engine surfaces etc. The surfaces of these heat transfer applications are either naturally rough owing to manufacturing techniques or become rough over a period of time during operation. These rough surfaces usually contain...

Thermal Decomposition Characteristics of Miscanthus and Ulva during Pyrolysis

Global warming, caused by the excessive release of greenhouse gases due to the use of fossil fuels, is the main reason why a switch to renewable energy sources is becoming a necessity. A renewable energy source with a high potential to contribute to the energy needs worldwide is biomass. Biomass can be used for the production of electricity and...

Experimental study of transport phenomena in the condenser of an OTEC-cycle

In the search for new forms of renewable energy production, an interesting option is to make use of the energy stored in the ocean in tropical areas. The sun heats up the surface water in these areas to a point it is feasible to generate electricity, using the temperature difference between the hot surface water and the cold ocean water at...

Small Scale Methanol Production: Process modelling and design of an autonomous, renewable container sized methanol plant

At the United Nations Climate Change Conference held in Paris in 2015, ambitious goals for the worldwide CO2 emissions were set. To achieve these goals, a huge reduction in CO2 emissions must be realized. For the energy market, the current aim is to use renewable electricity instead of fossil fuels. However, there are multiple sectors where...

Supercritical water gasification: Decomposition of lipids forming a substantial part of sewage sludge

Supercritical water gasification is a process in which wet biomass is converted to bio-syngas. In this process the temperature and pressure are raised above the critical point of water (374 C, 221 bar), creating a supercritical medium in which a high conversion and energetic efficiency of biomass to bio-syngas is realized. Due to these high...

Synergies in an integrated Ocean Thermal Energy system: Integration and optimization of OTEC, SWAC and Ecopark

Small tropical islands are facing major issues. Most of them rely on imported fossil fuels, which makes electricity generation both expensive and unsustainable. Moreover, small tropical islands are more vulnerable to the consequences of climate change than the mainland. Effects of climate change can be: more and more powerful hurricanes,...

Simulations of steady and oscillating flow in diffusers

In this thesis diffuser performance will be simulated with computational fluid dynamics, which will be done with the program Ansys Fluent. The expanding geometry creates an adverse pressure gradient and under certain conditions there will also be separation.<br/><br/>At first a relative simple simulation will be done of a one-directional...

Parametric Emission Prediction Model in Gas Turbines with Exhaust Gas Recirculation

One of the challenges in gas turbines is in the reduction of NOx and CO emissions due to simultaneous<br/>dependence on stringent emission norms and subsequent demand for change in operating conditions. To cater the volatile demand of power supply, most of the gas turbines have to be flexible to changing loads. Closer the load is to full load,...

Atmospheric Water Extraction: Fresh Water Production using Ocean Thermal Energy

Many regions in the world depend heavily on expensive desalinated water for fresh water consumption, in particular tropical areas. Current mainstream desalination technologies (Reverse Osmosis and Multi-Stage Flash Evaporation) are quite energy intensive and thus costly. Today’s challenge is to design a desalination system that could run with...

RANS-FGM simulation of n-heptane spray flame in OpenFOAM: A new implementation of flamelet generated manifold to account for enthalpy loss with detailed reaction mechanisms

The efficient and clean combustion of liquid fuels is a fundamental requirement in the design of future energy systems. Simulation plays a more and more important role in the design of such burners. In this work the spray combustion simulation approach introduced by Ma (2016) is improved, and validated against the CORIA Jet Spray Flame database ...

Evaluation of enhanced coalescing strategies for the recovery of stabilized oil droplets in the production of advanced biofuels

Development of a model of the combustion a single iron particle as a contribution to design of metal fuel burners

Recently an oxidation and reduction cycle of metals has been proposed as alternative for liquid fuel combustion. Out of several possible metals iron is an interesting candidate because the oxide does not form making it more easy to develop a cyclic process. As a first building block towards a computation or particle dust clouds here a...