Recommendations for computer code selection of a flow and transport code to be used in undisturbed vadose zone calculations for TWRS immobilized environmental analyses

This paper presents an over view of the "scaling strategy", in particular the role played by the counter part test methodology. The recent studies dealing with a scaling analysis in light water reactor with special regard to the VVER 1000 Russian reactor type are presented to demonstrate the phenomena important for scaling. The adopted scaling approach is based on the selection of a few characteristic parameters chosen by taking into account their relevance in the behavior of the transient. The adopted computer code used is RELAP5/Mod3.3 and its accuracy has been demonstrated by qualitative and quantitative evaluation. Comparing experimental data, it was found that the investigated facilities showed similar behavior concerning the time trends, and that the same thermal hydraulic phenomena on a qualitative level could be predicted. The main results are: PSB and LOBI main parameters have similar trends. This fact is the confirmation of the validity of the adopted scaling approach and it shows that PWR and VVER reactor type behavior is very similar. No new phenomena occurred during the counter part test, despite the fact that the two facilities had a different lay out, and the already known phenomena were predicted correctly by the code. The code capability and accuracy are scale-independent. Both character is tics are necessary to permit the full scale calculation with the aim of nuclear power plant behavior prediction. .

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Quantifying Vadose Zone Flow and Transport Uncertainties Using a Unified, Hierarchical Approach

10.2172/833660 ◽

2002 ◽

Author(s):

Philip D Meyer ◽

Christopher J Murray ◽

Mark L Rockhold ◽

Marcel Schaap

Keyword(s):

Vadose Zone ◽

Hierarchical Approach ◽

Flow And Transport

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Hydrodynamics characteristics of the small ships rudders

Analele Universităţii "Dunărea de Jos" din Galaţi. Fascicula XI, Construcţii navale/ Annals of "Dunărea de Jos" of Galati, Fascicle XI, Shipbuilding ◽

10.35219/annugalshipbuilding.2020.43.03 ◽

2020 ◽

Vol 43 ◽

pp. 21-26

Author(s):

Dan Obreja

Keyword(s):

Design Process ◽

Computer Code ◽

Short Description ◽

Research Centre ◽

Research Activities ◽

Optimum Position ◽

Practical Research ◽

Small Ship ◽

Control Forces ◽

Selection Of

The estimation of the hydrodynamics characteristics of the small ships rudders is an important issue in the initial design process. The manoeuvring performance depends on the type and geometry of the rudder. The control forces and moments generated by the rudder deflection can be calculated on the basis of the hydrodynamics characteristics of the rudder. A short description of the Mordvinov theoretical model is presented in this paper, in order to determine the hydrodynamics characteristics of a small ship rudder, with the propeller and hull influences. On the basis of the control forces and moments, the optimum position of the rudder stock and the selection of the steering gear can be performed. Using the Mordvinov method, the computer code PHP NM-MAN-HC was develop at the Research Centre of the Naval Architecture Faculty of “Dunarea de Jos” University of Galati. This computer code is integrated in the software platform PHP (Preliminary Hydrodynamics Performance) and is used for didactic applications and practical research activities in the small ship design process

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Characterization of hydraulic properties in the upper vadose zone for two aquifers in Slovenia

10.5194/egusphere-egu21-2407 ◽

2021 ◽

Author(s):

Vesna Zupanc ◽

Matjaž Glavan ◽

Miha Curk ◽

Urša Pečan ◽

Michael Stockinger ◽

...

Keyword(s):

Stable Isotopes ◽

Soil Water ◽

Water Flow ◽

Vadose Zone ◽

Hydraulic Properties ◽

Isotope Composition ◽

Transport Processes ◽

Precipitation Event ◽

Water Fluxes ◽

Flow And Transport

<p>Environmental tracers, present in the environment and provided by nature, provide integrative information about both water flow and transport. For studying water flow and solute transport, the hydrogen and oxygen isotopes are of special interest, as their ratios provide a tracer signal with every precipitation event and are seasonally distributed. In order to follow the seasonal distribution of stable isotopes in the soil water and use this information for identifying hydrological processes and hydraulic properties, soil was sampled three times in three profiles, two on Kr&#353;ko polje aquifer in SE Slovenia and one on Ljubljansko polje in central Slovenia. Isotope composition of soil water was measured with the water-vapor-equilibration method. Based on the isotope composition of soil water integrative information about water flow and transport processes with time and depth below ground were assessed. Porewater isotopes were in similar range as precipitation for all three profiles. &#160;Variable isotope ratios in the upper 60 cm for the different sampling times indicated dynamic water fluxes in this upper part of the vadose zone. Results also showed more evaporation at one sampling location, Brege. The information from stable isotopes will be of importance for further analyzing the water fluxes in the vadose zone of the study sties.&#160;<br>This research was financed by the ARRS BIAT 20-21-32 and IAEA CRP 1.50.18 Multiple isotope fingerprints to identify sources and transport of agro-contaminants. &#160;</p>

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Vadose Zone, Part I : Characterization and Flow Processes

Applied Stochastic Hydrogeology ◽

10.1093/oso/9780195138047.003.0016 ◽

2003 ◽

Author(s):

Yoram Rubin

Keyword(s):

Porous Media ◽

Water Flow ◽

Governing Equation ◽

Vadose Zone ◽

Stochastic Analysis ◽

Transport Processes ◽

Richards Equation ◽

Saturated Porous Media ◽

Flow And Transport ◽

Flow Processes

Many of the principles guiding stochastic analysis of flow and transport processes in the vadose zone are those which we also employ in the saturated zone, and which we have explored in earlier chapters. However, there are important considerations and simplifications to be made, given the nature of the flow and of the governing equations, which we explore here and in chapter 12. The governing equation for water flow in variably saturated porous media at the smallest scale where Darcy’s law is applicable (i.e., no need for upscaling of parameters) is Richards’ equation (cf. Yeh, 1998)

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A Parametric Analysis for Optimal Selection of a Gas Turbine Cogeneration System

Volume 4: Turbo Expo 2004 ◽

10.1115/gt2004-54317 ◽

2004 ◽

Author(s):

K. Sarabchi ◽

A. Ansari

Keyword(s):

Gas Turbine ◽

Pressure Ratio ◽

Computer Code ◽

Primary Energy ◽

Inlet Temperature ◽

Fuel Cost ◽

Energy Usage ◽

Turbine Inlet Temperature ◽

Cogeneration System ◽

Selection Of

Cogeneration is a simultaneous production of heat and electricity in a single plant using the same primary energy. Usage of a cogeneration system leads to fuel energy saving as well as air pollution reduction. A gas turbine cogeneration plant (GTCP) has found many applications in industries and institutions. Although fuel cost is usually reduced in a cogeneration system but the selection of a system for a given site optimally involves detailed thermodynamic and economical investigations. In this paper the performance of a GTCP was investigated and an approach was developed to determine the optimum size of the plant to meet the electricity and heat demands of a given site. A computer code, based on this approach, was developed and it can also be used to examine the effect of key parameters like pressure ratio, turbine inlet temperature, utilization period, and fuel cost on the economics of GTCP.

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