Study of the Gas Combustion LP in an Atmospheric Burner

2008 ◽  
Author(s):  
Armando Gallegos-Mun˜oz ◽  
Armando Balderas-Bernal ◽  
Alejandro Rami´rez-Barro´n ◽  
J. C. Prince-Avelino
Keyword(s):  
Fluid Dynamic ◽  
Premixed Combustion ◽  
Experimental Results ◽  
Experimental Measurements ◽  
Finite Rate ◽  
Gas Combustion ◽  
Finite Speed ◽  
Computational Fluids Dynamics ◽  
Computational Fluids ◽  
Laminar Flamelet

The study of the gas combustion LP in an atmospheric burner to bake ceramics is presented. The study includes different models from combustion and turbulence to find the best interaction chemistry-turbulence, applying Computational Fluids Dynamics (CFD) through FLUENT®. For the study different models of combustion were considered, where the finite speed of the reaction is important by means of kinetic chemistry from Arrhenius. The different models of combustion were; a generalized model of speed of Finite Rate/Eddy dissipation, non-premixed combustion Laminar Flamelet and Eddy dissipation. Each one of these models represents the combustion non-premixed of gas LP, to simulate the combustion of turbulent diffusive flames. For the study of the turbulence the model k-epsilon was applied. The results obtained for each combination turbulence-chemistry were compared with experimental measurements of temperature within the furnace. This comparison allowed making adjustments in the modeling of the process of combustion, identifying the best interaction between combustion and turbulence. According to the obtained results, the k-epsilon model represents adequately the fluid-dynamic development of the flame within the furnace. The models of combustion Finite Rate/Eddy dissipation and Laminar Flamelet show the best approach to the experimental results, where the k-epsilon model is applied to modeling the turbulence-chemistry interaction.

scholarly journals Numerical and experimental study of the dynamic factor of the dynamic load on the urban railway

2020 ◽  
Vol 29 (1) ◽  
pp. 195-202
Author(s):  
Tran Anh Dung ◽  
Mai Van Tham ◽  
Do Xuan Quy ◽  
Tran The Truyen ◽  
Pham Van Ky ◽  
...  
Keyword(s):  
Experimental Study ◽  
Dynamic Load ◽  
Dynamic Measurement ◽  
Experimental Results ◽  
Load Factor ◽  
Dynamic Factor ◽  
Experimental Measurements ◽  
Train Speed ◽  
Dynamic Load Factor

AbstractThis paper presents simulation calculations and experimental measurements to determine the dynamic load factor (DLF) of train on the urban railway in Vietnam. Simulation calculations are performed by SIMPACK software. Dynamic measurement experiments were conducted on Cat Linh – Ha Dong line. The simulation and experimental results provide the DLF values with the largest difference of 2.46% when the train speed varies from 0 km/h to 80 km/h

Finite Element Model to Predict the Bioconversion Rate of Glucose to Fructose using Escherichia coli K12 for Sugar Production from Date

2015 ◽  
Vol 11 (1) ◽  
pp. 105-113 ◽  
Author(s):  
Maher Trigui ◽  
Karim Gabsi ◽  
Walid Zneti ◽  
Suzelle Barrington ◽  
Ahmed Noureddine Helal
Keyword(s):  
Escherichia Coli ◽  
Induction Time ◽  
Volume Fraction ◽  
Element Model ◽  
Initial Concentration ◽  
Computational Fluids Dynamics ◽  
Date Syrup ◽  
Computational Fluids ◽  
Two Phases ◽  
Inoculum Volume

Abstract In this study, Bioconversion process of glucose to fructose from date syrup using Escherichia coli K12 is modeled using a commercial computational fluids dynamics (CFD) code fluent FLUENT 6.3.23 [8] which we implemented a user-defined functions (UDF) to simulate the interrelationships at play between various phases. A two phases CFD model was developed using an Eulerian – Eulerian approach to calculate the fructose volume fraction produced during time. The bioconversion process was studied as function of three initial concentration of glucose (0.14, 0.242 and 0.463gL–1), three induction time (60, 120 and 180 mn) and three inoculum volume (100, 120 and 150mL). The numerical results are compared with experimental data for bioconversion rate and show good agreement (R2= 0.894). The optimal condition of diffusion was obtained by applying an initial concentration of glucose less than 0.2gL–1 and induction time great than 100 minutes.

Design and Testing of Innovative Rotational Mould Heated by Thermal Fluid

2010 ◽  
Author(s):  
M. D. Monzo´n ◽  
A. N. Beni´tez ◽  
P. Bordo´n ◽  
P. M. Herna´ndez ◽  
M. D. Marrero ◽  
...  
Keyword(s):  
Cycle Time ◽  
Energetic Efficiency ◽  
Internal Stresses ◽  
Cycle Times ◽  
Transfer Processes ◽  
Computational Fluids Dynamics ◽  
Heating And Cooling ◽  
Computational Fluids ◽  
Plastic Parts ◽  
Design And Testing

Rotomoulded plastic parts have no internal stresses, as it is a process carried out at lower temperatures than injection moulding and no pressure is applied. The main disadvantage is the high cycle times needed. This paper focuses on reducing this cycle time and in producing a mould using standardized parts. For cycle time reducing, it is proposed to heat the mould by thermal fluid in continuous circulation; heat transfer processes have been studied for over 20 different configurations of the oil’s inlet – outlet, obtaining acceptable results with a manifold with 25 perforations in the front and rear faces. This configuration has been optimized by computational fluids dynamics, allowing reducing heating and cooling time and improving the energetic efficiency and the uniformity of heating. Design, simulations and testing of a 100 mm3 cube have been carried out in order to produce a standardized mould; this mould consists in some standardized parts and a nickel shell, obtained by rapid prototyping and electroforming process. This shell can be removed from the rest of elements in the mould, allowing thus to obtain parts with any other geometry just by changing the nickel shell. An experimental machine for testing has been developed as well.

scholarly journals SIMULASI DISTRIBUSI TEMPERATUR DAN KELEMBABAN RELATIF RUANGAN DARI SISTEM DEHUMIDIFIKASI MENGGUNAKAN COMPUTATIONAL FLUIDS DYNAMICS (CFD)

ROTASI ◽  
2017 ◽  
Vol 19 (1) ◽  
pp. 1
Author(s):  
Eflita Yohana ◽  
Bambang Yunianto ◽  
Ade Eva Diana
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Flow Simulation ◽  
Liquid Desiccant ◽  
Humidity Ratio ◽  
Computational Fluids Dynamics ◽  
Computational Fluids ◽  
Computational Fluid Dynamics Cfd

Dehumidifikasi merupakan proses pengurangan kadar uap air  yang berpengaruh terhadap besar nilai kelembaban relatif dan temperatur suatu ruangan. Dalam mengkondisikan kadar uap air dalam suatu ruangan tersebut agar dapat sesuai dengan kebutuhan, maka perlu diketahui distribusi kelembaban relatif dan temperatur dalam ruangan menggunakan Computational Fluid Dynamics (CFD). Pada penelitian ini, pengambilan data dilakukan selama 20 menit dan dilakukan pada pukul 08.00 WIB.  Liquid desiccant yang digunakan dijaga pada temperatur 10°C dengan variasi konsentrasi 40% dan 50%. Sensor DHT 11 dipasang pada lima sisi, atap, dinding, lantai, inlet, outlet, yang berfungsi untuk mencatat perubahan kelembaban dan temperatur selama pengujian berlangsung. Pada kondisi normal tanpa menyalakan alat dehumidifier, sensor mencatat temperatur rata-rata di dalam ruangan sebesar 29,9°C dan RH 58,9%. Simulasi dilakukan menggunakan software CFD Solidworks Flow Simulation 2014. Validasi hasil eksperimen dengan hasil simulasi dengan membandingan bahwa liquid desiccant 40% dan 50%, nozzle sprayer 0.2 mm dengan temperatur yang dijaga pada 10°C mempunyai distribusi yang cukup merata dengan konsentrasi 40% memiliki nilai RH terendah sebesar 65,21%, nilai RH tertinggi sebesar 68,99%, nilai ω = 18 gr/kg, serta mempunyai temperatur tertinggi 31,11°C dan temperatur terendah 30,05°C. Sedangkan dengan konsentrasi 50% distribusi dalam ruangan juga cukup merata karena memiliki nilai RH terendah sebesar 59,21%., nilai RH tertinggi sebesar 62,80%, nilai ω = 17 gr/kg, serta mempunyai temperatur tertinggi 31,71°C dan temperatur terendah 30,93°C. Sehingga liquid desiccant dengan konsentrasi 50% mempunyai nilai Humidity Ratio (ω) lebih rendah dibandingkan dengan yang memiliki konsentrasi 40%.

Application of Various Combustion Models to a Generic Combustor

2003 ◽  
Author(s):  
Lei-Yong Jiang ◽  
Ian Campbell
Keyword(s):  
Experimental Tests ◽  
Combustion Model ◽  
Discrete Ordinates ◽  
Experimental Measurements ◽  
Finite Rate ◽  
Zone Length ◽  
Combustion Models ◽  
The Mean ◽  
Heat Transfers ◽  
Good Agreement

The flow-field of a generic gas combustor with interior and exterior conjugate heat transfers was numerically studied. Results obtained from three combustion models, combined with the re-normalization group (RNG) k-ε turbulence model, discrete ordinates radiation model, and partial equilibrium NOx model are presented and discussed. The numerical results are compared with a comprehensive database obtained from a series of experimental tests. The flow patterns and the recirculation zone length are excellently predicted, and the mean axial velocities are in fairly good agreement with the experimental measurements, particularly at downstream sections for all three combustion models. The mean temperature profiles are also fairly well captured by the probability density function (PDF) and eddy dissipation (EDS) combustion models. The EDS-finite-rate combustion model fails to provide acceptable temperature field. In general, the PDF shows some superiority over the EDS and EDS-finite-rate models. NOx levels predicted by the EDS model are in reasonable agreement with the experimental measurements.

Development of a Natural Gas-Fired, Ultra-Low NOx Can Combustor for an 800 KW Gas Turbine

1991 ◽  
Author(s):  
K. O. Smith ◽  
A. C. Holsapple ◽  
H. K. Mak ◽  
L. Watkins
Keyword(s):  
Natural Gas ◽  
Gas Turbine ◽  
Premixed Combustion ◽  
Experimental Results ◽  
Nox Emissions ◽  
Variable Geometry ◽  
Lean Premixed Combustion ◽  
Full Load ◽  
Primary Zone ◽  
Lean Premixed

The experimental results from the rig testing of an ultra-low NOx, natural gas-fired combustor for an 800 to 1000 kw gas turbine are presented. The combustor employed lean-premixed combustion to reduce NOx emissions and variable geometry to extend the range over which low emissions were obtained. Testing was conducted using natural gas and methanol. Testing at combustor pressures up to 6 atmospheres showed that ultra-low NOx emissions could be achieved from full load down to approximately 70% load through the combination of lean-premixed combustion and variable primary zone airflow.

scholarly journals Simulation of Percolation Threshold, Tunneling Distance, and Conductivity for Carbon Nanotube (CNT)-Reinforced Nanocomposites Assuming Effective CNT Concentration

Polymers ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 114 ◽  
Author(s):  
Yasser Zare ◽  
Kyong Yop Rhee
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Percolation Threshold ◽  
Experimental Results ◽  
Filler Concentration ◽  
Experimental Measurements ◽  
Tunneling Conductivity ◽  
Tunneling Distance

This article suggests simple and new equations for the percolation threshold of nanoparticles, the tunneling distance between nanoparticles, and the tunneling conductivity of polymer carbon nanotubes (CNTs) nanocomposites (PCNT), assuming an effective filler concentration. The developed equations correlate the conductivity, tunneling distance, and percolation threshold to CNT waviness, interphase thickness, CNT dimensions, and CNT concentration. The developed model for conductivity is applied for some samples and the predictions are evaluated by experimental measurements. In addition, the impacts of various parameters on the mentioned terms are discussed to confirm the developed equations. Comparisons between the calculations and the experimental results demonstrate the validity of the developed model for tunneling conductivity. High levels of CNT concentration, CNT length, and interphase thickness, as well as the straightness and thinness of CNTs increase the nanocomposite conductivity. The developed formulations can substitute for the conventional equations for determining the conductivity and percolation threshold in CNT-reinforced nanocomposites.

Holographic measurement of the elastic–plastic boundary surrounding cold-expanded holes

1989 ◽  
Vol 24 (2) ◽  
pp. 103-106 ◽  
Author(s):  
R J Sanford ◽  
R E Link
Keyword(s):  
Holographic Interferometry ◽  
Experimental Results ◽  
Similar Process ◽  
Experimental Measurements ◽  
Cold Expansion ◽  
Elastic Plastic ◽  
Theoretical Predictions ◽  
Holographic Measurement

Experimental measurements of the elastic—plastic boundary surrounding split-sleeve cold-expanded holes in 7075-T651 aluminum were made using the technique of holographic interferometry. The levels of expansion investigated ranged from 1.5 per cent to 8.4 per cent. The experimentally determined elastic—plastic boundaries were compared with several theoretical predictions. The experimental results were also compared with the experimental results from another investigation of a similar process. Predictions of the elastic—plastic boundary based on the Hoffman—Sachs theory agreed with the experimental results for levels of cold expansion over the range 1.5—3 per cent expansion. The experimental results of this investigation predicted larger elastic—plastic boundaries than those measured in a separate investigation. Possible explanations for the differences are discussed.

Sign in / Sign up

Export Citation Format

Share Document