Turbulence Modeling for Heated Developing Supercritical Flows

In recent years, a considerable amount of research has been directed towards making energy generation more efficient to combat global warming. To aid this goal, the use of supercritical fluids (SCFs) is gaining a lot of traction. SCFs have only one phase and experience a sharp variation of thermophysical properties when heated sufficiently....

Turbulent channel flow with stable stratification beyond the Oberbeck-Boussinesq assumptions: A DNS study

Stratified turbulent flows abound in environmental and industrial settings. Examples are atmospheric boundary layer flows, the transport of nutrients and organisms and the mixing of heat and salinity in the oceans, fluid flow in heat exchangers, and the transport of reactants and products in chemical reactions. These examples and many others...

Feasibility study and concept design on the use of solid oxide fuel cells fuelled by methanol on board of an offshore patrol vessel

Currently, the energy transition is a topic for discussion and many organizations are taking measures to reduce the effects of climate change. Armed forces are exempt of these new regulations on the grounds of national security, but some have already started taking steps to reduce the amount of harmful emissions. Due to the high efficiency and...

Thermal Modelling of a Concept for a Hybrid Micro Combustion Generator

Mobile electronics or remote devices like sensors for the Internet of Things (IoT) require energy storage with increasing energy densities, approaching the limits of the widespread lithium batteries. At the same time, lithium batteries are subject to growing criticism about their environmental impact due to their raw materials and their mining...

Secondary Flows in Asymmetrical Contractions: A Numerical Study

Due to the global energy crisis, there is a growing need to make industrial processes more efficient and clean. One such method is to use effective and renewable working fluids in power and refrigeration cycles. Research in this field during the past decade has placed supercritical CO2 (SCO2) in the forefront due to its non-ideal properties and...

Assessment of nasal airflow simulations: On the accuracy and usage of CFD simulations for healthy and NAO patients

Nasal airway obstruction (NAO) is one of the most common symptoms in the human respiratory system and causes a considerable financial burden to both individuals and society. Currently, NAO detection is troublesome to achieve, which can influence the accuracy and effectiveness of clinical surgery. Although several objective measurement techniques...

Boiling Heat Transfer with Nanofluids: An Experimental Study

Recent advancements in the field of nanotechnology have proven to offer viable alternatives for energy production, transport, and storage. As far as thermal energy is concerned, nanofluids have emerged as a novel method to enhance heat transfer. Indeed, nanofluids exhibit superior thermal capabilities, which may be able to meet the requirement...

Implementing Finite Difference Schemes on Graphics Processing Units

The continued development of improved algorithms and architecture for numerical simulations is at the core of increased computational performance and, therefore, the ability to perform more complex and precise numerical simulations in less time in areas such as Computational Fluid Dynamics. Employing faster algorithms on more efficient...

Computational Modeling of A 50 kWth Indirectly Heated Bubbling Fluidized Bed Steam Reformer

The CFD modeling based on the two-fluid model (TFM) was used on studying the novel indirectly heated bubbling fluidized bed steam reformer (IHBFB-SR). This is a collaborative project between Petrogas and TU Delft for testing the advance’s reactor configuration, which indirectly supplies the heat via radiant burner on the center toward the...

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...

Numerical Study on the Driving and Damping of High-Frequency Instabilities in a Jet Flame Combustor

Lean premixed flames are being used in gas turbines to reduce the emission of NOx. Unfortunately, it results often in thermoacoustic instabilities. These instabilities are high amplitude pressure oscillations which cause damage to the combustion system, reduce efficiency, flame blow-off or flashback. While the cause for instabilities due to...