The flexible asymmetric shock tube (FAST): A Ludwieg tube facility for wave propagation measurements in high-temperature vapours of organic fluids

This paper describes the commissioning of the flexible asymmetric shock tube (FAST), a novel Ludwieg tube-type facility designed and built at Delft University of Technology, together with the results of preliminary experiments. The FAST is conceived to measure the velocity of waves propagating in dense vapours of organic fluids, in the so-called...

Critical point anomalies include expansion shock waves

From first-principle fluid dynamics, complemented by a rigorous state equation accounting for critical anomalies, we discovered that expansion shock waves may occur in the vicinity of the liquid-vapor critical point in the two-phase region. Due to universality of near-critical thermodynamics, the result is valid for any common pure fluid in...

Developments in the pre-combustion CO2 capture pilot plant at the Buggenum IGCC

N.V. Nuon (part of the Vattenfall Group) operates an IGCC in Buggenum and is developing a multi-fuel IGCC with CO2 capture and storage (Nuon Magnum) in Eemshaven, the Netherlands. In order to prepare for large-scale application of CO2 capture and storage, a CO2 capture pilot plant is constructed at the Buggenum IGCC plant and will be ready for...

Maximum intensity of rarefaction shock waves for dense gases

Modern thermodynamic models indicate that fluids consisting of complex molecules may display non-classical gasdynamic phenomena such as rarefaction shock waves (RSWs) in the vapour phase. Since the thermodynamic region in which non-classical phenomena are physically admissible is finite in terms of pressure, density and temperature intervals,...

The influence of molecular complexity on expanding flows of ideal and dense gases

This paper presents an investigation about the effect of the complexity of a fluid molecule on the fluid dynamic quantities sound speed, velocity, and Mach number in isentropic expansions. Ideal-gas and dense-gas expansions are analyzed, using the polytropic ideal gas and Van der Waals thermodynamic models to compute the properties of the fluid....

Admissibility region for rarefaction shock waves in dense gases

In the vapour phase and close to the liquid–vapour saturation curve, fluids made of complex molecules are expected to exhibit a thermodynamic region in which the fundamental derivative of gasdynamic ? is negative. In this region, non-classical gasdynamic phenomena such as rarefaction shock waves are physically admissible, namely they obey the...

Siloxanes: A new class of candidate Bethe-Zel’dovich-Thompson fluids

This paper presents a new class of Bethe-Zel’dovich-Thompson fluids, which are expected to exhibit nonclassical gasdynamic behavior in the single-phase vapor region. These are the linear and cyclic siloxanes, light silicon oils currently employed as working fluids in organic Rankine cycle turbines. State-of-the-art multiparameter equations of...

Real-Gas Effects in ORC Turbine Flow Simulations: Influence of Thermodynamic Models on Flow Fields and Performance Parameters

The analysis and design of turbomachinery is usually performed by means of fluid dynamic computations employing ideal gas laws. This can lead to inaccurate redictions for Organic Rankine Cycle (ORC) turbines, which operate partly in the nonideal thermodynamic region. The objective of this work is to evaluate the influence of different equations...

Real-Gas Effects in ORC Turbine Flow Simulations: Influence of Thermodynamic Models on Flow Fields and Performance Parameters

The analysis and design of turbomachinery is usually performed by means of fluid dynamic computations employing ideal gas laws. This can lead to inaccurate redictions for Organic Rankine Cycle (ORC) turbines, which operate partly in the nonideal thermodynamic region. The objective of this work is to evaluate the influence of different equations...

Molecular interpretation of nonclassical gas dynamics of dense vapors under the van der Waals model

The van der Waals polytropic gas model is used to investigate the role of attractive and repulsive intermolecular forces and the influence of molecular complexity on the possible nonclassical gas dynamic behavior of vapors near the liquid-vapor saturation curve. The decrease of the sound speed upon isothermal compression is due to the well-known...