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Статті в журналах з теми "620.187:620.1"
1
Shalish, Miriam, Leslie A. Will, Naomi Fukai, Bo Hou, and Bjorn R. Olsen. "Role of polycystin-1 in bone remodeling:Orthodontic tooth movement study in mutant mice." Angle Orthodontist 84, no. 5 (September 2014): 885–90. http://dx.doi.org/10.2319/082313-620.1.
Повний текст джерела
2
Bilbo, E. Erin, Steven D. Marshall, Karin A. Southard, Verrasathpurush Allareddy, Nathan Holton, Allyn M. Thames, Marlene S. Otsby, and Thomas E. Southard. "Long-term skeletal effects of high-pull headgear followed by fixed appliances for the treatment of Class II malocclusions." Angle Orthodontist 88, no. 5 (April 18, 2018): 530–37. http://dx.doi.org/10.2319/091517-620.1.
Повний текст джерелаАнотація:
ABSTRACT Objectives: The long-term skeletal effects of Class II treatment in growing individuals using high-pull facebow headgear and fixed edgewise appliances have not been reported. The purpose of this study was to evaluate the long-term skeletal effects of treatment using high-pull headgear followed by fixed orthodontic appliances compared to an untreated control group. Materials and Methods: Changes in anteroposterior and vertical cephalometric measurements of 42 Class II subjects (n = 21, mean age = 10.7 years) before treatment, after headgear correction to Class I molar relationship, after treatment with fixed appliances, and after long-term retention (mean 4.1 years), were compared to similar changes in a matched control group (n = 21, mean age = 10.9 years) by multivariable linear regression models. Results: Compared to control, the study group displayed significant long-term horizontal restriction of A-point (SNA = −1.925°, P < .0001; FH-NA = −3.042°, P < .0001; linear measurement A-point to Vertical Reference = −3.859 mm, P < .0001) and reduction of the ANB angle (−1.767°, P < .0001), with no effect on mandibular horizontal growth or maxillary and mandibular vertical skeletal changes. A-point horizontal restriction and forward mandibular horizontal growth accompanied the study group correction to Class I molar, and these changes were stable long term. Conclusions: One phase treatment for Class II malocclusion with high-pull headgear followed by fixed orthodontic appliances resulted in correction to Class I molar through restriction of horizontal maxillary growth with continued horizontal mandibular growth and vertical skeletal changes unaffected. The anteroposterior molar correction and skeletal effects of this treatment were stable long term.
3
D'Antò, Vincenzo, Roberto Rongo, Gianluca Ametrano, Gianrico Spagnuolo, Paolo Manzo, Roberto Martina, Sergio Paduano, and Rosa Valletta. "Evaluation of surface roughness of orthodontic wires by means of atomic force microscopy." Angle Orthodontist 82, no. 5 (September 2012): 922–28. http://dx.doi.org/10.2319/100211-620.1.
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4
Yoshihara, Toshihiro, Junichi Suzuki, and Yasutaka Yawaka. "Anomaly of cervical vertebrae found on orthodontic examination: 8-year-old boy with cleft lip and palate diagnosed with Klippel-Feil syndrome." Angle Orthodontist 80, no. 5 (September 2010): 975–80. http://dx.doi.org/10.2319/110409-620.1.
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Zhou, Si Zhu, and Hao Yong Zeng. "Parametric Design of Key Components in Downhole Motor." Key Engineering Materials 620 (August 2014): 187–92. http://dx.doi.org/10.4028/www.scientific.net/kem.620.187.
Повний текст джерелаАнотація:
Downhole motor is an instrument to drill oil wells, different from rotary drilling in working methods. While downhole motor works, the drilling stem of which remains still supplies power to bits directly so that a much higher transmission efficiency of power can be achieved. Downhole motor has been a key developing downhole tool recently. It is installed in a limited space with a certain diameter, asking for a higher power, so the design of which is rather difficult. This paper mainly studies the key components of downhole motor in structure design and its working characteristics. And parametric design employed in series design to shorten design cycle is presented in this paper. After taken Solidworks as a basic software platform and turbodrill turbine section with diameter of 245mm as an original model, parametric design of key components in downhole motor has been achieved by setting the parameters of key components, adding relations, editing program, creating a new part etc. Parametric design methods presented in this paper has already been applied in series design of downhole motor at Yangtze University.
6
Chen, Jing, Gui Shu Yin, and Yan Xue. "Research on Recovery Technology of the By-Product Low-Pressure Steam of Ammonia." Applied Mechanics and Materials 620 (August 2014): 187–91. http://dx.doi.org/10.4028/www.scientific.net/amm.620.187.
Повний текст джерелаАнотація:
In this paper, it is described that the design elements and the process of the recovery system for the by-product low-pressure steam of ammonia. And it is introduced the situation of application of this system, including the main equipments selection and control strategy. At last, the economic benefit after application is analyzed.
7
Mormann, Thomas J., and Wolfgang Jeitschko. "The Silver(I) Mercury(II) Oxide Nitrate with the Empirical Formula AgHg2NO5." Zeitschrift für Naturforschung B 54, no. 12 (December 1, 1999): 1489–94. http://dx.doi.org/10.1515/znb-1999-1202.
Повний текст джерелаАнотація:
The title compound was prepared by solid state reaction of Ag2O with Hg(NO3)2· H2O in air at 350 °C. Its crystal structure was determined from single-crystal diffractometer data: Pnma, a = 620.1(1) pm, b = 670.1(1) pm, c = 1267.5(2) pm, Z = 4, R = 0.026 for 586 structure factors and 33 variable parameters. The compound may be represented by the formula Ag(HgO)2NO3 . The mercury(II) together with the oxygen atoms form zig-zag chains with linear coordination of the mercury atoms. The oxygen atoms of these chains are linked via silver(I) atoms, thus forming two-dimensionally infinite nets, which contain the trigonal planar nitrate groups in interstices. Thus, only secondary Hg-O and Ag-O bond are formed between the nets.
8
Obaid, A. S., M. A. Mahdi, and Hassan Zainuriah. "Growth of Nanocrystalline PbS Thin Films by Solid-Vapor Deposition." Advanced Materials Research 620 (December 2012): 1–6. http://dx.doi.org/10.4028/www.scientific.net/amr.620.1.
Повний текст джерелаАнотація:
Solidvapor deposition was used to synthesize nanocrystalline PbS thin films on a Si (100) substrate. Lead sulfide (PbS) powder was first prepared and then heated to 1050 °C in a tube furnace. The resulting vapor was carried to the substrate zone by an argon flow. The structure of the nanocrystalline PbS thin films was determined by X-ray diffraction (XRD). The grain size of the PbS thin films and powder was also estimated by XRD. The surface morphology and stoichiometric ratio of these ingots were observed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy. The SEM image revealed that the film had a uniform surface morphology over the entire substrate. The optical absorbance of the deposited films and powder were measured by Fourier-transform infrared spectroscopy. The optical band gapEgof the samples was calculated using the Tauc formula. The absorption of the thin films was found to be higher than that of the powder and lower for the entire wavenumber range (15005000 nm). TheEgvalues of the films determined were 3647 nm (0.34 eV), and that of the powder was 3100 nm (0.40 eV).
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Balagizi, Akonkwa, Ahouansou Montcho Simon, Nshombo Muderhwa, and Lalèyè Philippe. "Caractérisation De La Pêche Au Lac Kivu." European Scientific Journal, ESJ 13, no. 21 (July 31, 2017): 269. http://dx.doi.org/10.19044/esj.2017.v13n21p269.
Повний текст джерелаАнотація:
This study was focused on the description of fishing gears on Lake Kivu. Data were collected from March 2012 to February 2014 in Goma, Bukavu, and Kibuye fishing stations. The study findings indicate that gill nets, beach seine, lift net, trammel net composed of two panels of small and larger meshes (mosquito net attached to lift net parts), mosquito net, longline, single line, pots, and cast net were identified as fishing gears used on Lake Kivu. Longline was more selective (2 species) in terms of species selection. The lift net presented the best catch (19.4 ± 11 kg), while the trammel net showed the highest CPUE (7.9 ± 6.1 kg/h). The large dimensions of gears and the long netting duration characterized gillnets (1023.2 ± 620.1 m2 ) and longline (10.3 ± 4.6 hours) respectively. Cast-nets (20mm) showed the largest mesh size, while mosquito nets (1 ± 0.3 mm) were the smallest.
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Tekerli, M., and S. Koçak. "Relationships between production and fertility traits in first lactation and life time performances of Holstein cows under subtropical condition." Archives Animal Breeding 52, no. 4 (October 10, 2009): 364–70. http://dx.doi.org/10.5194/aab-52-364-2009.
Повний текст джерелаАнотація:
Abstract. The objective of this study was to determine the relationships between milk yield and calving interval in first lactation and breeding efficiency, herd life and length of productive life of 1 293 Holstein cows maintained at Ceylanpinar State Farm in Southeast Anatolia from 1990 to 2002. The least-squares means of first lactation milk yield, lactation length and calving interval were 5 620.1 ± 76.6 kg, 315.5 ± 2.0 and 386.9 ± 2.6 days. The values for breeding efficiency, herd life and length of productive life were 94.9 %, 2 095.9 ± 34.7 and 1 257.2 ± 34.4 days. The year of first lactation had significant effect (P<0.05) on all traits except for calving interval and lactation length, and breeding efficiency was only affected by age at first insemination and age at first calving (P<0.05). Heritabilities were 0.27 ± 0.08 for milk yield, 0.02 ± 0.05 for lactation length, 0.06 ± 0.05 for calving interval, 0.05 ± 0.05 for breeding efficiency, 0.30 ± 0.08 for herd life and 0.29 ± 0.08 for length of productive life. Genetic and phenotypic correlations between different traits ranged from −0.49 to 0.99 and −0.37 to 0.99 respectively.
Дисертації з теми "620.187:620.1"
1
Ramírez, Anthony. "Ultrasonic grain refinement of magnesium alloys." Thesis, University of Portsmouth, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.494007.
Повний текст джерелаАнотація:
The thesis project investigates ultrasonic grain refinement (UGR) of magnesium alloys. It commences with a brief study of the grain refinement of both aluminium-containing and aluminium-free magnesium alloys, by means of typical inoculating additives. That provides a basis for understanding the effectiveness of ultrasonic grain refinement of magnesium alloys to be presented in the following chapters.
2
Fischer, Walter [Verfasser], and Holm [Akademischer Betreuer] Altenbach. "Modellierung und Berechnung von mechanischen Spannungen und Volumenänderungen bei Reaktionsharzen / Walter Fischer. Betreuer: Holm Altenbach." Magdeburg : Universitätsbibliothek, 2015. http://d-nb.info/1069159778/34.
Повний текст джерела
3
Konozsy, Laszlo. "Multiphysics CFD modelling of incompressible flows at Low and Moderate Reynolds Numbers." Thesis, Cranfield University, 2012. http://dspace.lib.cranfield.ac.uk/handle/1826/7860.
Повний текст джерелаАнотація:
In this Ph.D. thesis, a novel high-resolution Godunov-type numerical procedure has been
developed for solving the unsteady, incompressible Navier-Stokes equations for constant
and variable density flows. The proposed FSAC-PP approach encompasses both artificial
compressibility (AC) and fractional step (FS) pressure-projection (PP) methods of Chorin
[3, 4] in a unified solution concept. To take advantage of different computational strategies,
the FS and AC methods have been coupled (FSAC formulation), and further a PP
step has been employed at each pseudo-time step. To provide time-accurate solutions,
the dual-time stepping procedure is utilized. Taking the advantage of the hyperbolic nature
of the inviscid part of the AC formulation, high-resolution characteristics-based (CB)
Godunov-type scheme is employed to discretize the non-linear advective fluxes. Highorder
of accuracy is achieved by using from first- up to ninth-order interpolation schemes.
Time integration is obtained from a fourth-order Runge-Kutta scheme. A non-linear fullmultigrid,
full-approximation storage (FMG-FAS) acceleration technique has been further
extended to the FSAC-PP solution method to increase the efficiency and decrease the
computational cost of the developed method and simulations. Cont/d.
4
Grenville, R. K. "Blending of viscous Newtonian and pseudo-plastic fluids." Thesis, Cranfield University, 1992. http://hdl.handle.net/1826/4362.
Повний текст джерелаАнотація:
Blend times and power consumption have been measured for Newtonian and pseudo-
plastic fluids in agitated, baffled vessels with diameters of 0.30,0.61 and 1.83 m. The
viscosities of the fluids were selected to give a range of Reynolds numbers between 200
and 105. Four impellers were tested with diameters between T/3 and T/2 positioned at
T/3 clearance above the lowest point of the vessel base. The impellers were typical of
those found in the chemical industry.
5
Starr, Maxwell. "High-order methods for steady, unsteady and transitional flow over a cylinder." Thesis, Cranfield University, 2012. http://dspace.lib.cranfield.ac.uk/handle/1826/7859.
Повний текст джерелаАнотація:
In this thesis, the flow around a cylinder is chosen as a test case for higher-order
numerical reconstruction techniques. No direct comparison of these higher-order
methods has been carried out for this particular test case. Especially for low Mach
number, incompressible flows with Implicit Large Eddy Simulation method. The
cylinder test case is both a proven test case in literature, as well as a test case
that can be scaled up in terms of flow speed with other parameters remaining
unchanged. The scaling of flow speed around the cylinder allows ease of flow
regime change. Thus the flow was modelled in this thesis from laminar flow to
turbulent flow, going through a transitional regime in between.
The simulations were set up such that numerical reconstruction methods could
be directly compared to one another at the range of flow speeds, and subsequently
in both two-dimensional and three-dimensional flows. The numerical
reconstruction methods for the ILES cases ranged from first order reconstruction
through to higher-order methods as high as ninth-order (in the weighted
essentially non-oscillatory scheme). With the speed of computation for the twodimensional
simulations, it was possible to test all of these schemes directly with
one another. However, three-dimensional simulations require a significantly greater
CPU run-time. Therefore, based on the results of the two-dimensional simulations,
a group of the higher-order methods were chosen for continuing analysis
in the three-dimensional simulations.
In the laminar flow regime, all the numerical schemes agreed very well with
literature data. As the flow speed increased, discrepancies started to appear in
the results, to varying degrees based on the flow speed, the numerical scheme
used, and the dimensionality of the flow. An analysis of the results showed that
two-dimensional simulations were suitable up to Reynolds 300. From this flow speed onwards, three-dimensional simulations are deemed necessary. At lower
Reynolds number flows the two-dimensional simulations provided good predictions
of the flow. At the higher Reynolds numbers, the 3D simulations outperformed
the 2D simulations.
Specific numerical reconstruction schemes were found to perform better at
certain aspects of the flow. For example, the coefficients around the cylinder or
the velocities in the wake varied based solely on the numerical scheme used.
Finally, during the course of the post-processing of the simulations, a spectral
analysis was carried out. The flow field was analysed at specific points in the
wake (ranging from near, medium and far wake). The spectral analysis proved
suitable for examining the fluctuations in the wake of the cylinder, showing the
redistribution of energy in the wake towards higher frequencies. In addition, the
wake showed increased power densities for the fluctuations as the flow moved
away from the cylinder, before then decreasing again as dissipation into the surrounding
flow occurred.
6
Adedigba, A. G. "Two-phase flow of gas-liquid mixtures on horizontal helical pipes." Thesis, Cranfield University, 2007. http://dspace.lib.cranfield.ac.uk/handle/1826/5069.
Повний текст джерелаАнотація:
The aim of this study was to investigate hydrodynamic two -phase (namely
water and air) fluid flow characteristics in helical pipes of low amplitude and
straight pipes of the same internal-diameter and constructional material: the
results for the two pipes have then been compared.
One of the objectives was to measure pressure, pressure drop and liquid
holdup in the two pipes. These are universal dominant parameters in the oiland-
gas industry as they significantly impact on the exploitation and
conveyance of crude oil from wells or reservoirs to the process plant, where the
crude is refined. The second objective was to examine applications of the
helical pipe.
Experiments were performed on three different helical pipes of internal
diameters 25.4 mm, 50 mm and 100 mm and their straight counterparts. The
single-phase preliminary experimental results from the 25.4 mm internaldiameter
for both pipes have shown that both pressure and pressure drop are
higher in the helical pipe than in the straight pipe. The friction factors were also
evaluated for both pipes and found to be higher in the helical pipe than in the
straight pipe. The single-phase and two-phase experimental results for the 50
mm internal-diameter pipes confirmed the conclusions from the preliminary
experimental results. The two-phase results showed that slug flow occurred in
the straight pipe at certain superficial velocities of air and water, whereas at the
same superficial velocities of air and water, slug flow did not ensue in the helical
pipe - instead bubbly flow was observed. Stratified flow occurred in the straight
pipe at very low superficial velocities of air and water but under these same
conditions, bubbly flow ensued in the helical pipe.
A section of 100 mm internal-diameter helical pipe was installed at some
distance from a catenary-shaped riser, with a view to investigating the
effectiveness of the helical pipe in mitigating severe slugging. The results
showed promise as the section of the helical pipe proved to be successful in
reducing the menace of severe slugging. This novel finding is regarded as a
breakthrough for the oil-and-gas industry in this respect. This is because
hydrocarbon proven reserves in the off-shore (i.e. deep sea-water) environment
have been estimated to be close to 60%. All previous research studies over the
past decade to provide solution to the problem posed by severe slugging have
not yielded any appreciable results. This discovery also has the advantages of
reducing the demand on the topside (process) facility and the achievement of
stability of liquid production is resulted from the consequent flow assurance in
the pipeline and riser.
7
Strand, Russell K. "Smoothed particle hydrodynamics modelling for failure in metals." Thesis, Cranfield University, 2010. http://dspace.lib.cranfield.ac.uk/handle/1826/6773.
Повний текст джерелаАнотація:
It is generally regarded to be a difficult task to model multiple fractures leading to
fragmentation in metals subjected to high strain rates using numerical methods.
Meshless methods such as Smoothed Particle Hydrodynamics (SPH) are well suited to
the application of fracture mechanics, since they are not prone to the problems
associated with mesh tangling.
This research demonstrates and validates a numerical inter-particle fracture model for
the initiation, growth and subsequent failure in metals at high strain rate, applicable
within a Total Lagrangian SPH scheme. Total Lagrangian SPH performs calculations in
the reference state of a material and therefore the neighbourhoods remain fixed
throughout the computation; this allows the inter-particle bonds to be stored and tracked
as material history parameters. Swegle (2000) showed that the SPH momentum
equation can be rearranged in terms of a particle-particle interaction area. By reducing
this area to zero via an inter-particle damage parameter, the principles of continuum
damage mechanics can be observed without the need for an effective stress term, held at
the individual particles.
This research makes use of the Cochran-Banner damage growth model which has been
updated for 3D damage and makes the appropriate modifications for inter-particle
damage growth. The fracture model was tested on simulations of a 1D flyer plate impact
test and the results were compared to experimental data. The test showed that the model
can recreate the phenomena associated with uniaxial spall to a high degree of accuracy.
Some limited modelling was also conducted in 2 and 3 dimensions and promising
results were observed.
Research was also performed into the mesh sensitivity of the explosively driven Mock-
Holt experiment. 3D simulations using the Eulerian SPH formulation were conducted
and the best results were observed with a radial packing arrangement.
An in-depth assessment of the Monaghan repulsive force correction was also conducted
in attempt to eliminate the presence of the SPH tensile instability and stabilise the
available Eulerian SPH code. Successful results were observed in 1D, although the
results could not be replicated consistently in 2D. A further study was also conducted
into an approach that makes use of a partition of unity weighting to two different SPH
approximations of the same flow-field; one local and one non-local (or extended).
Unfortunately this approach could not be made to stabilise the code.
8
Antoniadis, Antonios Foivos. "High-order methods on mixed-element unstructured meshes for aeronautical applications." Thesis, Cranfield University, 2012. http://dspace.lib.cranfield.ac.uk/handle/1826/7891.
Повний текст джерелаАнотація:
Higher resolution and reliability are the desiderata for Computational Fluid Dynamics
and main drivers for the development, implementation and validation of highorder
accurate methods. Complex fluid dynamic phenomena such as shock-wave
boundary-layer interactions, turbulent separated flows and fluid problems involving
multiple scales are adequately resolved with high-order schemes. The spatial representation
of the flow field by an unstructured mesh provides flexibility, automation,
fast and effortless grid generation and exceptional load balance on multiple processor
computers. This plethora of advantages is mirrored by the unprecedented popularity
of unstructured-based schemes.
The objective of this PhD project is the implementation of two high-order schemes
for the compressible Navier-Stokes equations in the context of the finite volume “kexact”
framework: the MUSCL-TVD and WENO. The schemes are formulated in
two and three space dimensions for mixed-element unstructured meshes; in addition,
the Spalart-Allmaras turbulence model is implemented into the developed numerical
framework. A wide range of applications are considered spanning from low-speed
flows (M = 0.08) to supersonic conditions (M = 5.0); inviscid and viscous simulations
in a broad spectrum of Reynolds numbers ranging from Re = 500 up to Re = 37×106.
The applications include: the Taylor-Green vortex, the ONERA-M6 wing, flat plate,
the NACA-0012 and the MD 30P-30N aerofoils, and a shock-wave boundary-layer
interaction.
For the examined cases, WENO schemes demonstrate superior accuracy, numerical
dissipation and non-oscillatory behaviour over the MUSCL-TVD. High-order schemes
inherit low numerical dissipation properties while turbulence models induce dissipation,
this disequilibrium has adverse effects on the stability, convergence and accuracy
of the simulation; therefore, turbulence model re-calibration would be required in order
to accommodate high-order discretisation methods.
9
Karantonis, Konstantinos. "Modelling and simulation of turbulence in unsteady separated and suddenly-expanded flows." Thesis, Cranfield University, 2011. http://dspace.lib.cranfield.ac.uk/handle/1826/7900.
Повний текст джерелаАнотація:
The scope of this PhD thesis is the simulation of turbulence in time-dependent, separated
and suddenly-expanded channel flows. High-resolution and very high-order numerical
methods have been employed in the framework of Implicit Large Eddy Simulation (ILES)
to elucidate open questions about the physics in flows with sudden expansion.
It is well known that the planar sudden expansion (PSE), despite its simple and symmetric
geometry it produces a very complex behaviour and a distinctly asymmetric flow
pattern ascribed mainly to the Coanda effect. Such flows are encountered in a wide range
of practical engineering applications, such as combustion, hydraulic and fluidic devices,
air ducts, and mixing equipments. It is of great importance, therefore, to understand the
mechanisms that dominate flows with separation and reattachment of the shear layers, as
well as flows with regions of strong reversed motion.
This thesis has for the first time analysed in detail the turbulent kinetic energy budget
(TKEB) for the PSE. This analysis has been extended to examine the influence of Mach
number on each individual component of the TKEB. The resulting data can be used as
reference for further development of turbulence models capable of accurately resolving
the flow behaviour in suddenly-expanded flows.
Cont/d.
10
Mihaiescu, Adrian N. "Eddy viscosity turbulence models for compressible mixing." Thesis, Cranfield University, 2011. http://dspace.lib.cranfield.ac.uk/handle/1826/7982.
Повний текст джерелаАнотація:
The K - L and K - ϵ turbulence models are used to simulate the turbulent mixing induced
by the Rayleigh-Taylor and Richtmyer-Meshkov instabilities. The models contain
additional source terms for the turbulence kinetic energy which depend on the type of the
instability. A new criterion based on ratio of the averaged flow and turbulence time scales
is introduced for differentiating between the two types of instabilities. The original formulation
of the turbulence kinetic energy source present in the K - ϵ model is modified
in order to accurately capture the evolution of the Richtmyer-Meshkov instability in both
heavy/light and light/heavy configurations. Additional constraints are imposed to the
models in order to prevent non-physical solutions when strong gradients are present in the
flow.
Three test problems are considered and the performance of the turbulence models is assessed
by comparing their solutions with the results obtained by high resolution Implicit
Large Eddy Simulations (ILES). First, the classical Rayleigh-Taylor and Richtmyer-Meshkov
problems are solved. A new approach for initializing the turbulence models in proposed
for the Rayleigh-Taylor problem. It is found that both turbulence models describe successfully
the self similar growth of the Rayleigh-Taylor and Richtmyer-Meshkov instabilities
and can predict accurately the spatial distribution of the fluid concentrations and of the
turbulent kinetic energy. The last problem involves the mixing induced at two planar interfaces
by multiple shock reflections and refractions. The turbulence models estimate correctly
the evolution of the mixing and of the total kinetic energy in the mixing zones.
The transport equations of the turbulence models are solved numerically and the influence
of the numerical schemes on the results is investigated. It is concluded that the numerical
schemes do not have an important influence on the results in the case of the classical
Rayleigh-Taylor problem (provided that grid convergence has been achieved and the turbulence
models have been initialized using the method proposed here). However, in the
presence of shocks (such as in the case of the Richtmyer-Meshkov instability), the HLLC
Riemann solver should be used together with a reconstruction scheme of third or higher
order of accuracy.