A Fast Differential Deficit Control Volume Approach for Modeling Turbine-Turbine Interactions

Author(s):  
Milo DiPaola ◽  
David J. Willis
2013 ◽  
Vol 141 (7) ◽  
pp. 2526-2544 ◽  
Author(s):  
Xi Chen ◽  
Natalia Andronova ◽  
Bram Van Leer ◽  
Joyce E. Penner ◽  
John P. Boyd ◽  
...  

Abstract Accurate and stable numerical discretization of the equations for the nonhydrostatic atmosphere is required, for example, to resolve interactions between clouds and aerosols in the atmosphere. Here the authors present a modification of the hydrostatic control-volume approach for solving the nonhydrostatic Euler equations with a Lagrangian vertical coordinate. A scheme with low numerical diffusion is achieved by introducing a low Mach number approximate Riemann solver (LMARS) for atmospheric flows. LMARS is a flexible way to ensure stability for finite-volume numerical schemes in both Eulerian and vertical Lagrangian configurations. This new approach is validated on test cases using a 2D (x–z) configuration.


2011 ◽  
Vol 38 (8-9) ◽  
pp. 1027-1029 ◽  
Author(s):  
Gunwoo Kim ◽  
Myung Eun Lee

2014 ◽  
Vol 59 (1) ◽  
pp. 25-40 ◽  
Author(s):  
Jianwei Cheng ◽  
Yi Luo

Abstract Explosions originated from or around the sealed areas in underground coal mines present a serious safety threat. The explosibility of the mine atmosphere depends on the composition of oxygen, combustible and inert gases. In additional, the composition in the inaccessible sealed areas change with time under various factors, such as gases emissions, air leakage, inert gases injected, etc. In order to improve mine safety, in this paper, a mathematical model based on the control volume approach to simulate the atmosphere compositions is developed, and the expanded Coward explosibility triangle diagram is used to assess the mine gas explosion risk. A computer program is developed to carry out the required computations and to display the results. In addition, the USBM explosibility diagram is also included in the program to serve as a double check.


2000 ◽  
Author(s):  
Marcelo J. S. de Lemos ◽  
Marcos H. J. Pedras

Abstract Turbulent flow in a channel, totally and partially filled with a porous medium, is simulated with a proposed turbulence model. Two cases are analyzed, namely clear flow past a porous obstacle and flow through a porous medium having a cavity with a higher porosity. Mean and turbulence quantities were solved within both computational domains using a single numerical technique. The control volume approach was used to discretize the governing equations. In the first case analyzed, the flow penetration into the porous substrate is accompanied by generation of turbulence kinetic energy within the obstacle. In the second geometry, the flow is pushed towards the cavity as porosity increases.


2011 ◽  
Vol 312-315 ◽  
pp. 433-438 ◽  
Author(s):  
Ali Akbar Abbasian Arani ◽  
Mostafa Mahmoodi ◽  
Meysam Amini

The natural convection in a square cavity with a heated horizontal plate containing a nanofluid (water and Ag) is simulated numerically. The heated plate and vertical walls are maintained at a constant temperature, Th and Tc, while the horizontal walls are adiabatic. The nanofluid is assumed to be incompressible and the flow is considered to be laminar. The continuity, momentum and energy equations written in terms of the primitive variables are discretized using a control volume approach and the SIMPLER algorithm. A parametric study is performed and the effect of the Rayleigh number, the location of the heated plate and the volume fraction of the nanoparticles on the fluid flow and the heat transfer inside the cavity are investigated. The results show that the mean Nusselt number of the vertical walls increases with increasing the volume fraction of the nanoparticles. Moreover, for a constant volume fraction of the nanoparticles, the Nusselt number of the vertical walls decreases substantially as the location of the heated plate varies from top to bottom of the cavity.


2020 ◽  
Vol 330 ◽  
pp. 01044
Author(s):  
Syrine Khadhrawi ◽  
Fakhreddine Segni Oueslati ◽  
Rachid Bennacer

The present work is a numerical simulation of the mixed convection of an incompressible fluid in a horizontal channel under sun radiation partially filled with metal foam blocks. The Darcy-Brinkman model is adopted. The control volume approach is used to solve the motion and energy equations governing mixed convection. The study focuses on the effect of certain control parameters such as the Rayleigh number (Ra), the thermal conductivity ratio and the porosity on the flow structure and heat transfer. Indeed, the results for flow structures and temperature distribution are presented in the form of velocity fields with streamtraces and isotherms, while the average Nusselt number (Nu) is used to quantify heat transfer.


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