scholarly journals Smoke and heat flow in a large volume building in case of fire

2014 ◽  
Vol 13 (4) ◽  
pp. 057-065
Author(s):  
Wojciech Węgrzyński

In the paper the author presents some chosen methodologies used in the design process of natural smoke and heat ventilation systems and the use of Computational Fluid Dynamics (CFD) tools. Comparison of the performance of various systems was conducted on the basis of performed CFD analyses. The analysis was prepared with the use of ANSYS Fluent 14.5 package, with the use of RNG k-ε turbulence model. The results of analysis are presented, together with the additional design recommendations.

2016 ◽  
Vol 819 ◽  
pp. 356-360
Author(s):  
Mazharul Islam ◽  
Jiří Fürst ◽  
David Wood ◽  
Farid Nasir Ani

In order to evaluate the performance of airfoils with computational fluid dynamics (CFD) tools, modelling of transitional region in the boundary layer is very critical. Currently, there are several classes of transition-based turbulence model which are based on different methods. Among these, the k-kL- ω, which is a three equation turbulence model, is one of the prominent ones which is based on the concept of laminar kinetic energy. This model is phenomenological and has several advantageous features. Over the years, different researchers have attempted to modify the original version which was proposed by Walter and Cokljat in 2008 to enrich the modelling capability. In this article, a modified form of k-kL-ω transitional turbulence model has been used with the help of OpenFOAM for an investigative CFD analysis of a NACA 4-digit airfoil at range of angles of attack.


2013 ◽  
Vol 61 (1) ◽  
pp. 155-160 ◽  
Author(s):  
G. Sztarbała

Abstract The aim of this paper is to present the application of Computational Fluid Dynamics (CFD) to the assessment of conditions inside construction works during a fire. The CFD method is now commonly used to support the design process of fire safety in construction works. This method is very useful at the preliminary stage of design because it is possible to check the internal environment during a fire and evaluate whether requirements of fire safety are met


2012 ◽  
Vol 220-223 ◽  
pp. 1698-1702
Author(s):  
Jian Chen ◽  
Zhu Ming Su ◽  
Qi Zhou ◽  
Jian Ping Shu

A novel hydraulic rotary high speed on/off valve is investigated. The function of the outlet turbine and the effect on revolution speed of valve spool are analyzed. The inner fluid flow condition under full open case of the on/off valve is simulated using computational fluid dynamics(CFD) method based on Ansys/Fluent and velocity and pressure profiles of fluid inside valve are obtained. Suggestions on optimizing the geometry of valve to decrease transition losses are given.


2021 ◽  
Vol 23 (2) ◽  
Author(s):  
Elin Yusibani ◽  
Hidayatun Nisa ◽  
Rajibussalim Rajibussalim

Penelitian ini bertujuan untuk mensimulasikan distribusi temperatur dengan variasi radius channel garam dan temperatur masukan pada teras Molten Salt Breeder Reactor (MSBR). Computational Fluid Dynamics (CFD) dengan perangkat lunak Ansys Fluent digunakan pada simulasi ini untuk sebuah sel moderator. Variasi radius channel garam adalah 0,0108 m; 0,0208; dan 0,0308 m dengan panjang moderator 3,96 m. Variasi temperatur masukan adalah 809 K, 839 K, 859 K, dan 909 K. Hasil simulasi pada variasi radius menunjukkan bahwa dengan pertambahan sebesar 0,01 m memberikan kenaikan suhu sebesar 8 - 23 K pada temperatur masukan konstan. Perubahan terhadap temperatur masukan, diperoleh kenaikan temperatur keluaran antara 1 - 10 K, pada radius channel garam yang konstan. Dengan demikian dapat disimpulkan bahwa distribusi temperatur dalam teras MSBR akan meningkat jika radius channel garam diperkecil atau temperatur masukan dinaikkan.


2019 ◽  
Vol 19 (3) ◽  
pp. 345-447
Author(s):  
Luong Ngoc Loi ◽  
Nguyen Chi Cong ◽  
Ngo Van He

In this work, the commercial Computational Fluid Dynamics (CFD), ANSYS-Fluent V.14.5 has been used to illustrate the effects of rudder and blade pitch on hydrodynamic performances of a propeller. At first, the characteristic curves of a container ship propeller are computed. Then, effects of rudder on hydrodynamic performances of the propeller in the both cases of the propeller with and without rudder have been investigated. The relationships between the blade pitch angle and the hydrodynamic performances of the selected referent propeller in this work having designed conditions as diameter of 3.65 m; speed of 200 rpm; average pitch of 2.459 m and the boss ratio of 0.1730. Using CFD, the characteristic curves of the marine propeller, pressure distribution, velocity distribution around propeller and the efficiency of the propeller have been shown. From the obtained results, the effects of rudder and blade pitch angle on hydrodynamic performances of the propeller have been evaluated.


2021 ◽  
Author(s):  
Rajendra Prasad K S ◽  
Krishna V ◽  
Sachin Bharadwaj ◽  
Babu Rao Ponangi

Abstract Modelling of turbulence heat transfer for supercritical fluids using Computational Fluid Dynamics (CFD) software is always challenging due to the drastic property variations near critical point. Use of Artificial Neural Networks (ANN) along with numerical methods have shown promising results in predicting heat transfer coefficients of heat exchangers. In this study, accuracy of four different turbulent models available in the commercial CFD software - Ansys Fluent is investigated against the available experimental results. The k-e Re Normalization Group (RNG) model with enhanced wall treatment is found to be the best-suited turbulence model. Further, K-e RNG Turbulence Model is used in CFD for parametric analysis to generate the data for ANN studies. A total of 1,34,698 data samples were generated and fed into the ANN program to develop an equation that can predict the heat transfer coefficient. It was found that, for the considered range of values the absolute average relative deviation is 3.49%.


2012 ◽  
Vol 135 (1) ◽  
Author(s):  
Luigi Martinelli ◽  
Antony Jameson

Aeronautics, and in particular aerodynamics, has been one of the main technological drivers for the development of computational fluid dynamics (CFD). This paper presents a personal account of the main advances in the development of solvers and shape optimization techniques, which have contributed to make CFD an essential part of the design process of modern aircraft.


2014 ◽  
Vol 556-562 ◽  
pp. 1338-1341
Author(s):  
Yang Sheng Zhao ◽  
Xiao Ping Du

To research the radiation properties of heat flow around the aircrafts’ surface in hypersonic flight, a fusion algorithm to calculate the radiation of flow around hypersonic aircrafts is proposed in this paper. Firstly, the algorithm use the computational fluid dynamics (CFD) to calculate the basic aerodynamic parameters of the aircrafts which are inside boundary layer, such as pressure, density, etc. Subsequently, the model of the radiation of flow around aircrafts is built by using the engineering algorithm. Then, we can build the model of the radiation properties of heat flow around the surface of the aircrafts effectively. The result can reflect the distribution of the radiation of heat flow around surfaces of the aircrafts accurately, and provide data support to study its optical detection and thermal protection.


Author(s):  
Alexandre T. P. Alho

In response to the need for better designs in less time and at low costs, computational fluid dynamics (CFD) is becoming an integral part of the vessel’s design process. Recent studies have shown that CFD techniques can be used with relative success for the problem of ship resistance prediction. This paper reports on the simulation of the flow around a typical catamaran hull by means of CFD computations. The numerical model used in the simulations was developed in full scale with the experimental model in order to eliminate any source of scale effects. The paper presents a discussion on grid configuration and an analysis of the performance of the numerical model in describing the characteristics of the in-between hulls flow. The results obtained were validated against experimental data.


Sign in / Sign up

Export Citation Format

Share Document