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Optimization of cyclone geometry for maximum collection efficiency . Yunardi; Ilham Maulana; . Elwina; . Wusnah; Novi Sylvia; Yazid Bindar
Proceedings of The Annual International Conference, Syiah Kuala University - Life Sciences & Engineering Chapter Vol 1, No 2 (2011): Engineering
Publisher : Syiah Kuala University

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Abstract

This paper presents the results obtained from the application of both computational fluid dynamics (CFD) Fluent 6.3 and Design Expert codes to modelling and optimizing a gas-solid cyclone separator based upon its geometrical parameters. A pre-processor software GAMBIT was employed to set up the configuration, discretisation, and boundary conditions of the cyclone.  A commercial CFD code FLUENT 6.3 was employed to simulate the flow field and particle dynamics in the cyclone. The optimization study was performed under either a constant gas inlet flow rate of 0.075 m3/s or a constant inlet gas velocity of 18 m/s. A response surface methodology with three levels (-1, 0, and +1) was employed as the experimental design. Independent variables to be optimized include the ratio of inlet gas width to diameter of the cyclone, W/D, the ratio of conical length to diameter, Lc/D and the ratio outlet diameter to cyclone diameter De/D. The response variables of collection efficiency and pressure drop were correlated in the forms of quadratic polynomial equations. The simultaneous optimization of the response variables has been implemented using a desirability function (DF) approach, computed with the aid of Design Expert software.  The results of investigation showed that at constant flow rate, the following optimum ratios of W/D =0,28, Lc/D =1,5,  and De/D =0,52 were obtained to give a collection efficiency of 90% and a pressure drop of 155 Pa. At the constant inlet gas velocity, the following optimum ratios of W/D =0,25, Lc/D =1,5,  and De/D =0,57 were obtained to give a collection efficiency of 90% and a pressure drop of 190 Pa. This findings indicate that gas inlet treatment at either constant flow rate or constant inlet gas velocity does not produce significant difference on the collection efficiency, but does give significant influence on the pressure drop.
Analysis of turbulence models performance for the predictions of flow yield, efficiency, and pressure drop of a gas-solid cyclone separator Novi Sylvia; . Yunardi; Ilham Maulana; . Elwina; . Wusnah; Yazid Bindar
Proceedings of The Annual International Conference, Syiah Kuala University - Life Sciences & Engineering Chapter Vol 1, No 2 (2011): Engineering
Publisher : Syiah Kuala University

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Abstract

This paper presents the results obtained from the application of computational fluid dynamics (CFD) to modelling the flow field of a Lapple cyclone and to optimizing the cyclone based upon its geometrical parameters. A pre-processor software GAMBIT was employed to set up the configuration, discretisation, and boundary conditions of the cyclone.  The characteristics of the cyclone being studied was 0.2 m in diameter, receiving a gas flow rate of 0.1 m3/s with a particle mass loading of 0.01 kg/m3.  A commercial CFD code FLUENT 6.2.16 was employed to simulate the flow field and particle dynamics in the cyclone. The objective of this research was to investigate the performance of a number of turbulence models on the prediction of the flow field, collection efficiency and pressure drop in the Lapple cyclone. A number of five turbulence models under Reynolds Averaged Navier Stokes (RANS) category, including Spallart-Allmaras, standard k-ε model, RNG k-ε model, standard k-ω model, and Reynolds Stress Model (RSM) were examined in the simulation of the flow field and particle dynamics inside the cyclone. A validation of all calculation was performed by comparing the predicted results in terms of axial and tangential velocities, efficiency and pressure drop against experimental data of a Lapple cyclone taken from literature. The results of the investigation show that out of five turbulence models being tested, the RSM presented the best predicted results. The predictions of axial and tangential velocities as well as cyclone efficiency by this model are in excellent agreement with the experimental data.  Although the pressure drop in the cyclone is under-predicted, the RSM predictions are far better than those of other model. Other turbulence models are over-predicted and under-predicted the axial and tangential velocity, respectively.  With respect to efficiency and pressure drop of the cyclone, other models are capable of following the trend of the experimental data but they failed to agree with the experimental values.  These results suggest that the RSM is the most suitable turbulence model to represent the flow field and particle dynamics inside a cyclone gas-solid separator.
Comparative performance study of two simple soot models for the prediction of soot level in atmospheric turbulent non-premixed flames . Elwina; . Yunardi; Novi Sylvia; . Wusnah; Yazid Bindar
Proceedings of The Annual International Conference, Syiah Kuala University - Life Sciences & Engineering Chapter Vol 1, No 2 (2011): Engineering
Publisher : Syiah Kuala University

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Abstract

The increase of current fossil fuel consumption has led to an increase of soot emission into atmosphere.  Accurate prediction of soot production and destruction in a combustion system is not only important for the purpose of the design of the system, but also vital for the operation of the combustor. Numerous soot models have been proposed to predict the soot production and destruction in a flame, categorized as empirical, semi-empirical and detailed soot models.  Although the detailed model represents the highest level of soot modelling, its use has been impaired by substantial requirement of resources of computer and time. Therefore, empirical and semi-empirical approaches still have their position in soot modelling of practical combustors. In this study, two soot models, single-step and two-step models are examined in the simulation of atmospheric turbulent non-premixed sooting flames. The soot models are compared and evaluated for their performance in predicting soot level in methane and ethylene non-premixed flames.  The commercial software Fluent 6.3 was used to perform the calculations of flow and mixing fields, combustion and soot. Standard k-ε and eddy dissipation models were selected as solvers for the representation of the turbulence and combustion, respectively.  The two soot models used in the study are available directly from the code for evaluation. The results show that the two-step model clearly performed far better than the single-step model in predicting the soot level in both methane and ethylene non-premixed flames. With a slight modification in the constant a of the soot formation equation, the two-step model was capable of producing prediction of soot level closer to experimental data.  In contrast, the single-soot model produced very poor results, leading to a significant under-prediction of soot levels in both flames.
Computational fluid dynamics of crosswind effect on a flare flame . Wusnah; . Yunardi; Ilham Maulana; . Elwina; Novi Sylvia; Yazid Bindar
Proceedings of The Annual International Conference, Syiah Kuala University - Life Sciences & Engineering Chapter Vol 1, No 2 (2011): Engineering
Publisher : Syiah Kuala University

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Abstract

This paper presents the results obtained from the application of computational fluid dynamics (CFD) to modelling the crosswind effect on a turbulent non-premixed flame. A pre-processor software GAMBIT was employed to set up the configuration, discretisation, and boundary conditions of the flame being investigated.  The commercial software Fluent 6.3 was used to perform the calculations of flow and mixing fields as well as combustion. Standard k-ε and eddy dissipation models were selected as solvers for the representation of the turbulence and combustion, respectively.  The results of all calculations are presented in the forms of contour profiles.  During the investigation, the treatment was performed by setting a constant velocity of fuel at 20 m/s with varied cross-wind velocity and by keeping the cross-wind velocity constant at 1.1 m/s with varied fuel velocity.  The results of the investigation showed that the standard k-ε turbulence model in conjunction with Eddy Dissipation Model representing the combustion was capable of producing reliable phenomena of the flow field and reactive scalars field in the turbulent non-premixed flame being investigated. Other results of the investigation showed that increasing the velocity of the crosswind, when the fuel velocity was kept constant, significantly affected the flow field, temperature and species concentrations in the flare flame. On the other hand, when the velocity of the fuel was varied at the constant crosswind velocity, the increasing velocity of the fuel gave positive impact as it enabled to counteract the effect of crosswind on the flare flame
Simulation of the crosswind and the steam addition effect on the flare flame . WUSNAH; . YUNARDI; NOVI SYLVIA; . ELWINA; YAZID BINDAR
Proceedings of The Annual International Conference, Syiah Kuala University - Life Sciences & Engineering Chapter Vol 4, No 1 (2014): Engineering
Publisher : Syiah Kuala University

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Abstract

This paper presents the results obtained from the application of computational fluid dynamics (CFD) to modelling the crosswind and steam addition effect on a turbulent non-premixed flame. A pre-processor software GAMBIT was employed to set up the configuration, discretisation, and boundary conditions of the flame being investigated.  The commercial software Fluent 6.3 was used to perform the calculations of flow and mixing fields as well as combustion. Standard k-ε and eddy dissipation models were selected as solvers for the representation of the turbulence and combustion, respectively.  The results of all calculations are presented in the forms of contour profiles.  During the investigation, the treatment was performed by setting a  velocity of fuel at 20 m/s with varied cross-wind velocity at  3.77 m/s, 7.5 m/s and 10 m/s,  and steam/fuel ratio at 0.14, 0.25 and 2.35.  The results of the investigation showed that the standard k-ε turbulence model in conjunction with Eddy Dissipation Model representing the combustion was capable of producing reliable phenomena of the flow field and reactive scalars field in the turbulent non-premixed flame being investigated. Other results of the investigation showed that increasing the velocity of the crosswind, when the fuel velocity was kept constant, significantly affected the flow field, temperature and species concentrations in the flare flame. On the other hand, when the velocity of the fuel was varied at the constant crosswind velocity, the increasing velocity of the fuel gave positive impact as it enabled to counteract the effect of crosswind on the flare flame. The velocity of the crosswind very influence of combustion efficiency, from result of the investigation showed that increasing the velocity of the crosswind significantly affected the combustion efficiency, other result of the inverstigation showed that steam addition will very influencing combustion, excelsior the steam/fuel ratio results the combustion efficiency decrease
APLIKASI PEMANFAATAN TAWAS DARI LIMBAH KALENG COCACOLA MENGGUNAKAN PELARUT HCl DALAM PROSES PENJERNIHAN AIR LIMBAH Arif Setiawan; Azhari Azhari; Masrullita Masrullita; Novi Sylvia; jalaluddin jalaluddin
Chemical Engineering Journal Storage (CEJS) Vol 1, No 4 (2022): Chemical Engineering Journal Storage (CEJS) - April 2022
Publisher : LPPM Universitas Malikussaleh

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29103/cejs.v1i4.5934

Abstract

Semua kaleng minuman rata-rata terbuat dari aluminium sehingga sangat memungkinkan untuk dimanfaatkan dalam pembuatan tawas. Tawas atau alum adalah suatu senyawa aluminium sulfat dengan rumus kimia [Al2(SO4)212H2O].  Tujuan dari penelitian ini adalah untuk memanfaatkan kandungan aluminium yang terkandung di dalam kaleng minuman bekas untuk pembuatan tawas kemudian tawas tersebut dimanfaatkan untuk penjernihan air. Pada penelitian ini digunakan konsentrasi HCl 20 % dan H2SO4 9M dan berat sampel 5 gram dimana nilai yield yang diperoleh yaitu 52,36%. Hasil penjernihan air kolam dengan turbidity awal 27,83 NTU dan pH 7,6 pada waktu 1 jam dan massa tawas 0,5 gr didapat turbidity 17,40 NTU dan pH 3,9 tetapi dari penelitian ini hasil penjernihan air yang terbaik yaitu pada dosis tawas 0,5 gr dengan waktu penjernihan 2,5 jam.