Correlation of Hydrogen Heat Transfer in Boiling and Supercritical Pressure States
Correlation of hydrogen heat transfer in boiling and supercritical pressure states
HEAT TRANSFER↗
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Results for “supercritical”
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Monte carlo calculations for the two-dimensional triangular lattice gas- supercritical region
Two-dimensional triangular lattice gas - monte carlo calculations in supercritical region
MONTE CARLO METHOD↗
Calculation of convective heat transfer at supercritical pressure
Convective heat transfer in stabilized turbulent flow of homogeneous liquid in circular channel under supercritical pressure
TURBULENT FLOW↗
Heat exchange in the supercritical region during the flow of piped carbonic acid and water
Experimental study on local heat transfer during turbulent flow of piped carbonic acid and water in supercritical region with state variables
SUPERCRITICAL PRESSURE↗
Characteristics of supercritical turbulence from Direct Numerical Simulations of C(sub 7)H(sub 16)/N(sub 2) and O(sub 2)/H(sub 2)
Analysis of Direct Numerical Simulations (DNS) transitional states of temporal, supercritical mixing layers for C7H16/N2 and O2/H2 shows that the evolution of all layers is characterized by the formation of high-density-gradient magnitude (HDGM) regions.
supercritical turbulence↗
Disintegration of fluids under supercritical conditions from mixing layer studies
Databases of transitional states obtained from Direct Numerical simulations (DNS) of temporal, supercritical mixing layers for two species systems, O2/H2 and C7H16/N2, are analyzed to elucidate species-specific turbulence aspects and features of fluid disintegration.
mixing layers supercritical combustion↗
Helicity in supercritical temporal mixing layers
Databases of transitional states obtained from Direct Numerical Simulations (DNS) of temporal, supercritical mixing layers for two species systems, 02/H2 and C7Hle/N2, are analyzed to elucidate species-specific turbulence aspects.
helicity supercritical flows↗
Characteristics of supercritical transitional temporal mixing layers
Several direct numerical simulation realizations of supercritical, three-dimensional, temporal mixing layers are used to investigate aspects of interest to turbulent combustion.
supercritical temporal mixing layers↗
Area production in supercritical, transitional mixing layers for reactive flow applications
An investigation of surface area production is conducted for supercritical mixing layers; the results are relevant to flame area evolution and fluid disintegration. In this study, the surface is chosen perpendicular to the mass fraction gradient.
area production in supercritical mixing layers↗
Supercritical (and Subcritical) Fluid Behavior and Modeling: Drops, Streams, Shear and Mixing Layers, Jets and Sprays
A critical review of recent investigations in the real of supercritical (and subcritical) fluid behavior is presented with the goal of obtaining a perspective on the peculiarities of high pressure observations.
supercritical fluids↗
Entropy Production of Emerging Turbulent Scales in a Temporal Supercritical N-Neptane/Nitrogen Three-Dimensional Mixing Layer
A study of emerging turbulent scales entropy production is conducted for a supercritical shear layer as a precursor to the eventual modeling of Subgrid Scales (from a turbulent state) leading to Large Eddy Simulations.
supercritical turbulence entropy production↗
The D(sub 2) Variation for Polydisperse Clusters of Lox Drops in Hydrogen at Supercritical Conditions
A study of polydisperse clusters of fluid drops at supercritical pressures has been conducted using a previously validated model of subcritical/supercritical isolated fluid drop behavior.
supercritical liquid oxygen hydrogen↗
Aspects of supercritical turbulence: direct numerical simulation of O2/H2 and C7H16/N2 temporal mixing layers
Results from Direct Numerical Simulations of temporal, supercritical mixing layers for two species systems are analyzed to elucidate species-specific turbulence aspects.
supercritical↗
Transitional mixing in a binary species supercritical, temporal mixing layer
A model of a binary species supercritical temporal mixing layer has been presented and applied to the study of the heptane/nitrogen system.
supercritical↗
Supercritical Water Oxidation and a Preliminary Concept for Lunar Application
Abstract: Water is a critical resource for crewed space exploration missions and reclamation of aqueous waste streams presents the only long-term viable option. Although early Artemis missions are considering water as part of the payload manifest, it would be extremely advantageous if follow-on missions were supplied—either in total or in part—by a reclamation technology that would operate autonomously between missions. An attractive technology is currently under ongoing research at NASA Glenn Research Center (GRC) that employs a Supercritical Water Oxidation (SCWO) process to destroy all hydrocarbons in the waste stream. Testing of an aqueous waste stream simulant, typical of what is generated on the International Space Station (ISS), has shown reductions in Total Organic Carbon (TOC) of greater than 99% with reactor residence times less than 30 s. Recent effort has been directed toward developing a conceptual design based on the current tubular reactor used in the evaluation of the conversion of SCWO. This conceptual design along with the results of recent SCWO conversion experiments will be presented. Recent design enhancements to achieve shorter residence times along with “production simulation” tests will be presented. The diagnostics used in assessing the extent of the waste conversion include a total organic carbon (TOC) analysis, Raman analyses, and measurements of pH, turbidity, and conductivity. Results obtained from the modified reactor configuration will also be compared to those of the Phase I configuration presented in earlier work.
SCWO↗
Supercritical CO2 Heat Pumps and Power Cycles for Concentrating Solar Power: Preprint
Pumped Thermal Energy Storage (PTES) is a promising technology for electricity storage applications. Grid electricity drives a heat pump which moves energy from a cold space to a hot space, thereby creating hot and cold thermal storage. The temperature difference between the storage is later used to drive a heat engine and return electricity to the grid. In this article, supercritical carbon dioxide (sCO2) is chosen as the working fluid for PTES, and results are compared to ‘conventional’ systems that use an ideal gas. Molten salts are used for the hot storage which means that a CSP plant with thermal storage and an sCO2 power cycle could potentially be hybridized with PTES by the addition of a heat pump. This article describes some of the benefits of this combined system which can provide renewable power generation and energy management services. Two methods by which an sCO2 heat pump can be combined with an sCO2 power cycle for CSP are described and techno-economic results are presented. Results indicate that these systems can achieve reasonable technical performance, but that costs are currently high.
41 EE - Solar Energy Technologies Office (EE-4S)↗
High-Fidelity Simulations of Supercritical CO2 Based Oxy-Combustion with Non-Ideal Equation of State
The supercritical carbon dioxide (sCO2) Allam-Fetvedt cycle employs high-temperature oxy-combustion using sCO2 as the working fluid, leading to a unique and challenging environment for materials. In this cycle, pressurized gaseous fuel is combusted in the presence of a hot oxidant flow containing a mixture of CO2 and oxygen and a hot CO2 diluent recycle stream at approximately 300 bar under lean combustion conditions. We present high-fidelity reacting simulations of this oxy-combustor environment and compare the results when performing simulations with ideal and non-ideal equations of state. By doing so, we identify if the combustor behavior at the regime of interest is sensitive enough to the equation of state to justify the added computational cost incurred with a non-ideal equation of state.
equation of state↗
Adaptive Mesh Refinement Large Eddy Simulation of the Supercritical Carbon Dioxide Round Turbulent Jet
Supercritical carbon dioxide (sCO2) is of interest to a range of engineering problems, including carbon capture, utilization, and storage (CCUS) as well as advanced cycles for power generation. Non-ideal variations in physical properties of sCO2 impact the physics of these systems. In this study, we simulate turbulent sCO2 jets to gain a better understanding of these physics.We use a second order finite volume method with adaptive mesh refinement as implemented in the first-principles simulation code PeleC to perform a Large Eddy Simulation (LES) of three turbulent jets of sCO2. Additionally, we use the Soave-Redlich-Kwong equation of state to close the system and examine the impact of a cubic equation of state on the turbulent flow physics. We look at velocity and Reynolds stress profiles at different downstream locations for three cases in which the temperature of the jet andthat of the ambient fluid differ in order to capture the effects of widely varying thermal properties in the pseudocritical region. These results are then contrasted with established theory for ideal gas jets.
adaptive mesh refinement↗