Comparative Performance Study of Two Simple Soot Models for the Prediction of Soot Level in Atmospheric Turbulent Non-premixed Flames

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

CFD Analysis of Efficiency and Pressure Drop in a Gas-solid Square Cyclones Separator

In this paper, two small cyclones with the same hydraulic diameter and volume, which one is square and the other one is round (Lapple cyclone), are numerically compared. 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/s. A commercial CFD code FLUENT 6.2.16 was employed to simulate the flow field and particle dynamics in the cyclone. The Reynolds averaged Navier–Stokes equations with Reynolds Stress Turbulence Model (RSTM) are solved by use of the finite volume method based on the SIMPLE pressure correction algorithm in the computational domain. The Eulerian–Lagrangian computational procedure is used to predict particles tracking in the cyclones. The velocity fluctuations are simulated using the Discrete Random Walk (DRW).The results show that collection efficiency of square cyclone is the better with increasing flow rate than round cyclone. The pressure drop in square cyclone is higher than the pressure drop in small round one

Computational Fluid Dynamics of Crosswind Effect on a Flare Flame

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 flam

Desiminasi Teknologi Pengeringan Dan Pengasapan Ikan Lele Pada UMKM Di Desa Meunasah Lhok Kecamatan Muara Batu Kabupaten Aceh Utara

Kegiatan ini dilakukan kepada UMKM Aceh Catfish dan kelompok Seungkoe Atjeh dalam menghasilkan produk ikan lele asap dan ikan lele kering yang merupakan peternak lele yang baru mulai berkembang dan memulai usaha dengan membuat ikan lele kering yang berada di desa Meunasah Lhok kecamatan Muara Batu kabupaten Aceh Utara. Selama ini ikan lele di jual melalui pengumpul dengan harga yang tidak menentu pada saat ikan lele di panen, sehingga ikan lele yang tidak tertampung oleh pengumpul mengakibatkan ikan lele menjadi besar dan sulit untuk di jual. Oleh UMKM Aceh Catfish dan kelompok Seungkoe Atjeh ikan lele yang di panen dibuat sebuah produk ikan lele kering. Ikan lele kering yang diproduksi peternak dilakukan masih secara konvensional menggunakan sinar matahari. Lokasi pengolahan ikan lele kering juga kurang hygienies. Pengolahan ikan lele kering yang dilakukan masih sederhana menyebabkan produk ikan lele kering yang dihasilkan kualitasnya kurang baik seperti warna dan daging yang kurang kering merata karena tergantung oleh kondisi cuaca selain itu daya tahan atau daya simpan ikan lele kering singkat. Didukung dengan kemasan yang masih sederhana. Untuk memecahkan masalah dalam hal meningkatkan produktivitas, nilai tambah dan daya saing produk yang berbasis iptek, pengusul melakukan kegiatan diseminasi produk teknologi berupa teknologi pengeringan dan teknologi pengasapan ikan lele dengan menggunakan oven pengering dan pengasapan.Kegiatan ini dilakukan kepada UMKM Aceh Catfish dan kelompok Seungkoe Atjeh dalam menghasilkan produk ikan lele asap dan ikan lele kering yang merupakan peternak lele yang baru mulai berkembang dan memulai usaha dengan membuat ikan lele kering yang berada di desa Meunasah Lhok kecamatan Muara Batu kabupaten Aceh Utara. Selama ini ikan lele di jual melalui pengumpul dengan harga yang tidak menentu pada saat ikan lele di panen, sehingga ikan lele yang tidak tertampung oleh pengumpul mengakibatkan ikan lele menjadi besar dan sulit untuk di jual. Oleh UMKM Aceh Catfish dan kelompok Seungkoe Atjeh ikan lele yang di panen dibuat sebuah produk ikan lele kering. Ikan lele kering yang diproduksi peternak dilakukan masih secara konvensional menggunakan sinar matahari. Lokasi pengolahan ikan lele kering juga kurang hygienies. Pengolahan ikan lele kering yang dilakukan masih sederhana menyebabkan produk ikan lele kering yang dihasilkan kualitasnya kurang baik seperti warna dan daging yang kurang kering merata karena tergantung oleh kondisi cuaca selain itu daya tahan atau daya simpan ikan lele kering singkat. Didukung dengan kemasan yang masih sederhana. Untuk memecahkan masalah dalam hal meningkatkan produktivitas, nilai tambah dan daya saing produk yang berbasis iptek, pengusul melakukan kegiatan diseminasi produk teknologi berupa teknologi pengeringan dan teknologi pengasapan ikan lele dengan menggunakan oven pengering dan pengasapan

Desiminasi Teknologi Pengeringan Dan Pengasapan Ikan Lele Pada UMKM Di Desa Meunasah Lhok Kecamatan Muara Batu Kabupaten Aceh Utara

&#x0D; &#x0D; &#x0D; &#x0D; Kegiatan ini dilakukan kepada UMKM Aceh Catfish dan kelompok Seungkoe Atjeh dalam menghasilkan produk ikan lele asap dan ikan lele kering yang merupakan peternak lele yang baru mulai berkembang dan memulai usaha dengan membuat ikan lele kering yang berada di desa Meunasah Lhok kecamatan Muara Batu kabupaten Aceh Utara. Selama ini ikan lele di jual melalui pengumpul dengan harga yang tidak menentu pada saat ikan lele di panen, sehingga ikan lele yang tidak tertampung oleh pengumpul mengakibatkan ikan lele menjadi besar dan sulit untuk di jual. Oleh UMKM Aceh Catfish dan kelompok Seungkoe Atjeh ikan lele yang di panen dibuat sebuah produk ikan lele kering. Ikan lele kering yang diproduksi peternak dilakukan masih secara konvensional menggunakan sinar matahari. Lokasi pengolahan ikan lele kering juga kurang hygienies. Pengolahan ikan lele kering yang dilakukan masih sederhana menyebabkan produk ikan lele kering yang dihasilkan kualitasnya kurang baik seperti warna dan daging yang kurang kering merata karena tergantung oleh kondisi cuaca selain itu daya tahan atau daya simpan ikan lele kering singkat. Didukung dengan kemasan yang masih sederhana. Untuk memecahkan masalah dalam hal meningkatkan produktivitas, nilai tambah dan daya saing produk yang berbasis iptek, pengusul melakukan kegiatan diseminasi produk teknologi berupa teknologi pengeringan dan teknologi pengasapan ikan lele dengan menggunakan oven pengering dan pengasapan.&#x0D; &#x0D; &#x0D; &#x0D; </jats:p

Ceramic Membrane Production from the Mixture Composition of Clay, Zeolite, Activated Carbon with Micro Particle Size

The study has been done in membrane production from the ratio of clay, zeolite and activated carbon. The goal of this study is to make membrane from clay, zeolite and activated carbon with micro particle size using Planetary Ball Milling Fritsch Pulverisette. The comparison of clay, zeolite and activated carbon is 80% : 10% : 10%, 70% : 20% : 10%, 60% : 30% : 10%, 50% : 40% : 10% with temperature combustion 600 °C, 700 °C dan 800 °C. Activated zeolite done with using HCl 2 M and then heated at 150 °C for 3 hours. Size particle from zeolite is 140 mesh with using Planetary Ball Milling Fritsch Pulverisette to reduce size of zeolite become 140 mesh with a rotation speed of 350 rpm for 6 hours. The result of this study shows that the highest flukes membrane found in clay, zeolit and activated membrane at 50%: 40%: 10% with temperature combustion at 800 °C around 4,859 L/jam.m2. The compressive strength on clay: zeolite: activated carbon ( 80%: 10%: 10%) with temperature burning at 600 °C around 39,6977 kg/cm2. Characterization testing using Scanning Electron Microscopy (SEM) on ceramic membranes with clay composition: zeolite: activated carbon = 50%: 40%: 10% at a combustion temperature of 600 °C obtained by membrane pore size of 2,699 μm. Adsorption with the optimum time obtained at 1 hour with a concentration of 0,2333 ppm. The highest effect of membrane composition on cation exchange capacity (CEC) is in the composition of 50%: 40%: 10% with a combustion temperature of 600 °C which is equal to 1.1 mgrek/g..</jats:p