Numerical Modelling of Gas Foil Journal Bearings: Analysis of High-Pressure Lubrication Flows

In the pursuit of reducing the climate impact of aviation, there has been an increased interest in the adoption of renewable energy technologies. Examples of revolutionary technologies include hydrogen fuel cell systems and waste heat recovery using the organic Rankine cycle. The design of viable energy conversion systems for aviation poses...

High Fidelity Simulations and Modelling of Dissipation in Boundary Layers of Non-ideal Fluid Flows

In this work, we investigate the sources of dissipation in adiabatic boundary layers of non-ideal compressible fluid flows. Direct numerical simulations of transitional, zero-pressure gradient boundary layers are performed with an in-house solver considering two fluids characterized by different complexity of the fluid molecules, namely air...

Flow deviation and critical choking in transonic turbine cascades operating with non-ideal compressible flows

In this work we examine the flow deviation and its relationship to critical choking, i.e., choking of the meridional component of velocity, in transonic turbine cascades operating with non-ideal compressible flows. To this purpose, a generalized expression of the corrected flow per unit area as a function of both the thermodynamic state and...

Validation of the SU2 Flow Solver for Classical Non Ideal Compressible Fluid Dynamics

The validation of SU2 for modelling classical non-ideal compressible fluid dynamics will advance the research into efficient ORC turbomachinery design. This study determines the validity of the two-dimensional flow solver for predicting the isentropic expansion of Siloxane MM through a converging-diverging nozzle using...

Machine-learnt design guidelines for axial vanes in Supersonic turbines operating with non-ideal compressible flows

The scientific community is consistently focused on identifying new sources of energy, which can reduce the consequences of climate change and depleting natural resources. Organic Rankine Cycle (ORC) based power systems have been touted as one of the promising technologies of extracting thermal energy from waste-heat and renewable sources such...

Entropy generation in laminar boundary layers of non-ideal fluid flows

This paper documents a numerical study on entropy generation in zero-pressure gradient, laminar boundary layers of adiabatic non-ideal compressible fluid flows. The entropy generation is expressed in terms of dissipation coefficient $$C:\mathrm {d}$$ and its dependency on free-stream Mach number, fluid molecular complexity, and flow non...

Real Gas Thermodynamics: and the isentropic behavior of substances

A generalized isentropic gas model is derived following earlier work by Kouremenos et al. in the 1980s, by replacing the traditional adiabatic exponent γ by the real exponents γPv, γTv, and γPT, describing the isentropic pressure-volume, temperature-volume, and pressure-temperature relations respectively. The real adiabatic exponents are...

Experimental Observation of Non-Ideal Compressible Fluid Dynamics: with Application in Organic Rankine Cycle Power Systems