scholarly journals Comparison of polar ozone loss rates simulated by one-dimensional and three-dimensional models with Match observations in recent Antarctic and Arctic winters

2007 ◽  
Vol 112 (D12) ◽  
Author(s):  
Om Prakash Tripathi ◽  
Sophie Godin-Beekmann ◽  
Franck Lefèvre ◽  
Andrea Pazmiño ◽  
Alain Hauchecorne ◽  
...  
Keyword(s):  
Three Dimensional ◽  
One Dimensional ◽  
Ozone Loss ◽  
Dimensional Models ◽  
Three Dimensional Models ◽  
Polar Ozone ◽  
Loss Rates

scholarly journals Analysis of high-rise constructions with the using of three-dimensional models of rods in the finite element program PRINS

2018 ◽  
Vol 33 ◽  
pp. 02033
Author(s):  
Vladimir Agapov
Keyword(s):  
Rectangular Cross Section ◽  
Three Dimensional ◽  
Free Vibrations ◽  
Finite Element Program ◽  
One Dimensional ◽  
Static And Dynamic Analysis ◽  
High Rise ◽  
Element Program ◽  
Dimensional Models ◽  
Three Dimensional Models

The necessity of new approaches to the modeling of rods in the analysis of high-rise constructions is justified. The possibility of the application of the three-dimensional superelements of rods with rectangular cross section for the static and dynamic calculation of the bar and combined structures is considered. The results of the eighteen-story spatial frame free vibrations analysis using both one-dimensional and three-dimensional models of rods are presented. A comparative analysis of the obtained results is carried out and the conclusions on the possibility of three-dimensional superelements application in static and dynamic analysis of high-rise constructions are given on its basis.

Modeling of Combustion in Gasoline Direct Injection Engines for the Optimization of Engine Management System Through Reduction of Three-Dimensional Models to (n × One-Dimensional) Models

2003 ◽  
Vol 125 (3) ◽  
pp. 520-532 ◽  
Author(s):  
P. Emery ◽  
F. Maroteaux ◽  
M. Sorine
Keyword(s):  
Direct Injection ◽  
Three Dimensional ◽  
Gasoline Direct Injection ◽  
Computational Time ◽  
Combustion Model ◽  
Dimensional Model ◽  
One Dimensional ◽  
Dimensional Models ◽  
Three Dimensional Models ◽  
The One

Gasoline direct injection (GDI) spark ignition engines may be able to run over a wide range of operating conditions. The GDI process allows combustion with lean mixtures which may lead to improved fuel economy and emissions relative to homogeneous spark ignition (SI) engines. To satisfy the different modes of operation, the tuning of GDI engines requires a large number of engine tests which are time-consuming and very expensive. To reduce the number of tests, a model with a very short computational time to simulate the engines in the whole operating range is needed; therefore the objective of this paper is to present a reduced model to analyze the combustion process in GDI engines, applied to a homogeneous stoichiometric mode. The objective of the model is to reproduce the same tendencies as those obtained by three-dimensional models, but with a reduced computational time. The one-dimensional model is obtained thanks to a reduction methodology based on the geometry of the combustion front computed with three-dimensional models of the KIVA-GSM code, a modified version of KIVA-II code including a CFM combustion model. The model is a set of n one-dimensional equations (i.e., for n rays), taking into account a thin flame front, described with the flamelet assumption. It includes a CFM combustion model and a (k,ε)-model including the mean air motions (swirl and tumble). The results of the one-dimensional model are compared to those obtained by the KIVA IIGSM under different engine conditions. The comparison shows that the one-dimensional model overestimates the maximum cylinder pressure, which has an insignificant effect on the net indicated work per cycle. The results obtained by the numerical simulations are close to those given by the three-dimensional model, with a much reduced computation time.

A Comparison Study of One-Dimensional Models for Stratified Thermal Storage Tanks

1989 ◽  
Vol 111 (3) ◽  
pp. 204-210 ◽  
Author(s):  
Y. H. Zurigat ◽  
K. J. Maloney ◽  
A. J. Ghajar
Keyword(s):  
Three Dimensional ◽  
Thermal Storage ◽  
Comparison Study ◽  
Storage Tanks ◽  
Factors Affecting ◽  
One Dimensional ◽  
Mixing Parameters ◽  
Dimensional Models ◽  
Three Dimensional Models ◽  
The One

A survey of the stratified thermal storage tank one-dimensional models available in the literature has been conducted. Six of these models were tested and compared against the experimental data obtained at our laboratories and from the literature. Although various factors affecting the performance of a stratified tank can be accounted for by the higher order models, i.e. two- and three-dimensional models, the introduction of empirically-based mixing parameters into the one-dimensional models renders them widely applicable and practical in the simulation of energy systems incorporating thermal storage tanks.

Multicode Prediction of the Influence of the Exhaust System on the Performance of a Turbocharged Engine

2002 ◽  
Vol 124 (3) ◽  
pp. 695-701 ◽  
Author(s):  
G. Chiatti ◽  
O. Chiavola
Keyword(s):  
Gas Flow ◽  
Fluid Dynamic ◽  
Flow Behavior ◽  
Three Dimensional ◽  
Engine Performance ◽  
Exhaust System ◽  
One Dimensional ◽  
Fast Processing ◽  
Dimensional Models ◽  
Three Dimensional Models

A multicode approach, based on the simultaneous use of zero-dimensional, one-dimensional, and three-dimensional models, has been developed and tested, and is here applied to predict the thermodynamic and fluid dynamic phenomena that characterize the unsteady gas flow propagation along the exhaust system of a turbocharged four-cylinder engine. The investigation is carried out by applying each model in a different region of the geometry, allowing to obtain detailed information of the flow behavior in complex elements, such as junctions, avoiding the significant limitations that a one-dimensional scheme always introduces, as well as fast processing typical of one-dimensional and zero-dimensional models, devoted to the analysis of ducts and volumes. The effect of the influence of different configurations of the exhaust system on the engine performance is analyzed.

scholarly journals Study on Calculation Models of Earth-Air Heat Exchanger Systems

2014 ◽  
Vol 2014 ◽  
pp. 1-15 ◽  
Author(s):  
Trilok Singh Bisoniya ◽  
Anil Kumar ◽  
Prashant Baredar
Keyword(s):  
Heat Exchanger ◽  
Three Dimensional ◽  
Cooling Capacity ◽  
Air Flow Rate ◽  
Pipe Length ◽  
One Dimensional ◽  
Dimensional Models ◽  
Three Dimensional Models ◽  
Depth Of Burial ◽  
Calculation Models

Modeling is very useful tool in order to predict the effect of the operating parameters like pipe length, radius, depth of burial and air flow rate on the thermal performance and heating/cooling capacity of earth-air heat exchanger (EAHE) systems. Till date many researchers have carried out a number of studies on calculation models for earth-air heat exchanger systems. The analysis of EAHE systems started with the development of one-dimensional models. The two-dimensional models came into practice during the 1990s and were replaced by three-dimensional models in recent years. Latest models are dynamic and technically more advanced which can provide room for all types of grid geometry to produce detailed thermal analysis of EAHE systems. This paper reviews on calculation models of EAHE systems as of the end of March, 2014.

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