Temperatures in and under a slab-on-ground floor: two- and three-dimensional numerical simulations and comparison with experimental data

2000 ◽  
Vol 35 (7) ◽  
pp. 655-662 ◽  
Author(s):  
M.H Adjali ◽  
M Davies ◽  
S.W Rees ◽  
J Littler
Keyword(s):  
Experimental Data ◽  
Numerical Simulations ◽  
Three Dimensional ◽  
Ground Floor ◽  
Comparison With Experimental Data

scholarly journals CFD Code Validation against Stratified Air-Water Flow Experimental Data

2008 ◽  
Vol 2008 ◽  
pp. 1-7 ◽  
Author(s):  
F. Terzuoli ◽  
M. C. Galassi ◽  
D. Mazzini ◽  
F. D'Auria
Keyword(s):  
Experimental Data ◽  
Numerical Simulations ◽  
Water Flow ◽  
Nuclear Reactor ◽  
Cold Water ◽  
Three Dimensional ◽  
Free Surface Flow ◽  
Surface Flow ◽  
Two Phase ◽  
Code Validation

Pressurized thermal shock (PTS) modelling has been identified as one of the most important industrial needs related to nuclear reactor safety. A severe PTS scenario limiting the reactor pressure vessel (RPV) lifetime is the cold water emergency core cooling (ECC) injection into the cold leg during a loss of coolant accident (LOCA). Since it represents a big challenge for numerical simulations, this scenario was selected within the European Platform for Nuclear Reactor Simulations (NURESIM) Integrated Project as a reference two-phase problem for computational fluid dynamics (CFDs) code validation. This paper presents a CFD analysis of a stratified air-water flow experimental investigation performed at the Institut de Mécanique des Fluides de Toulouse in 1985, which shares some common physical features with the ECC injection in PWR cold leg. Numerical simulations have been carried out with two commercial codes (Fluent and Ansys CFX), and a research code (NEPTUNE CFD). The aim of this work, carried out at the University of Pisa within the NURESIM IP, is to validate the free surface flow model implemented in the codes against experimental data, and to perform code-to-code benchmarking. Obtained results suggest the relevance of three-dimensional effects and stress the importance of a suitable interface drag modelling.

Numerical simulations of the flow through the inlet and isolator of a Mach 4 dual mode scramjet

2012 ◽  
Vol 116 (1182) ◽  
pp. 833-846 ◽  
Author(s):  
S. Janarthanam ◽  
V. Babu
Keyword(s):  
Experimental Data ◽  
Numerical Simulations ◽  
Three Dimensional ◽  
Pressure Rise ◽  
Dual Mode ◽  
Flow Distortion ◽  
Capture Ratio ◽  
Boundary Interaction ◽  
Numerical Predictions ◽  
Mass Capture

Abstract Results from numerical simulations of the three dimensional flow in the intake-isolator of a dual mode scramjet are presented. The FANS calculations have utilised the SST k -ω turbulence model. The effect of cowl length and cowl convergence angle on the inlet mass capture ratio, flow distortion, shock strength and pressure rise are studied in detail. Three cowl lengths and four or five cowl convergence angles for each cowl length are considered. The predicted values of the dimensionless wall static pressure and inlet mass capture ratio are compared with experimental data reported in the literature. The numerical predictions are shown to agree well with the experimental data. In addition, details of the flow field such as shocks, expansion fans and shock boundary interaction are also captured accurately. Inlet unstart is also demonstrated for one case.

A Pyramidal Lattice Frame: Pathways to Inversion

2020 ◽  
pp. 2150020
Author(s):  
Yue Guan ◽  
Lawrence N. Virgin
Keyword(s):  
Experimental Data ◽  
3D Printing ◽  
Numerical Simulations ◽  
Physical System ◽  
Discrete Model ◽  
Lattice Structure ◽  
Three Dimensional ◽  
Lateral Load ◽  
Structural Inversion ◽  
3D Printed

This paper considers the load–deflection behavior of a pyramid-like, shallow lattice structure. It consists of four beams that join at a central apex and when subject to a lateral load, it exhibits a propensity to snap-through: a classical buckling phenomenon. Whether this structural inversion occurs, and the routes by which it happens, depends sensitively on geometry. Given the often sudden nature of the instability, the behavior is also examined within a dynamics context. The outcome of numerical simulations are favorably compared with experimental data extracted from the testing of three-dimensional (3D)-printed specimens. The key contributions of this paper are that despite the continuous nature of the physical system, its behavior (transient and equilibria) can be adequately described using a discrete model, and the paper also illustrates the utility of 3D-printing in an accessible research context.

Numerical Investigation of a Centrifugal Compressor for Supercritical CO2 Cycles

2020 ◽  
Author(s):  
Renan Emre Karaefe ◽  
Pascal Post ◽  
Marwick Sembritzky ◽  
Andreas Schramm ◽  
Francesca di Mare ◽  
...  
Keyword(s):  
Experimental Data ◽  
Thermodynamic Properties ◽  
Flow Field ◽  
Numerical Simulations ◽  
Centrifugal Compressor ◽  
Supercritical Co2 ◽  
Solution Method ◽  
Three Dimensional ◽  
Solution Procedure ◽  
Test Loop

Abstract In this work, the performance characteristics and the flow field of a centrifugal compressor operating with supercritical CO2 are investigated by means of three-dimensional CFD. The considered geometry is based on main dimensions of the centrifugal compressor installed in the supercritical CO2 compression test-loop operated by Sandia National Laboratories. All numerical simulations are performed with a recently developed in-house hybrid CPU/GPU compressible CFD solver. Thermodynamic properties are computed through an efficient and accurate tabulation technique, the Spline-Based Table Look-Up Method (SBTL), particularly optimised for the applied density-based solution procedure. Numerical results are compared with available experimental data and accuracy as well as potentials in computational speedup of the solution method in combination with the SBTL are evaluated in the context of supercritical CO2 turbomachinery.

Theoretical Evaluation of the Effects of the Impeller Entrance Geometry and of the Incident Angle on Cavitation Inception in Centrifugal Pumps

1995 ◽  
Vol 209 (1) ◽  
pp. 29-38 ◽  
Author(s):  
G Ardizzon ◽  
G Pavesi
Keyword(s):  
Experimental Data ◽  
Pressure Drop ◽  
Present Model ◽  
Incident Angle ◽  
Three Dimensional ◽  
Centrifugal Pumps ◽  
Theoretical Evaluation ◽  
Cavitation Inception ◽  
Cavitation Performance ◽  
Comparison With Experimental Data

A method, based on quasi three-dimensional analysis, of describing pump cavitation behaviour is proposed. Cavitation performance is related to impeller entrance design and the influence of the angle of attack of the leading edges on the flow is studied. Coefficients are derived from the pressure drop due separately to the vanes and shroud. The influence of incident angle on cavitation is shown as a function of the blade geometry and discussed. By comparison with experimental data on centrifugal pumps, it is shown that the present model can simulate the characteristics of inception cavitation at design and off-design conditions.

Sign in / Sign up

Export Citation Format

Share Document