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"Penggunaan bahan bakar minyak (BBM), seperti bensin, solar, minyak tanah, mengakibatkan peningkatan produksi untuk bahan bakar minyak, sehingga ketersediaan minyak bumi yang ada semakin menipis, selain itu hasil pembakaran pada kendaraan bermotor menghasilkan polusi udara yang menjadi salah satu faktor pemanasan global. Masalah tersebut perlu dipecahkan dengan cara mencari energi alternatif yang lebih bersih dengan nilai oktan tinggi serta ketersediaanya di alam masih banyak yaitu gas alam dengan komposisi utama gas metana (CH4). Sebagai tempat penyimpanan digunakan compressed natural gas (CNG) dengan tabung bertekanan 20 MPa. Adsorbed natural gas (ANG) merupakan solusi untuk mengurangi tekanan dalam tabung sekitar 3,5 - 4 MPa memanfaatkan proses adsorpsi menggunakan karbon aktif. Adsorpsi adalah fenomena fisik yang terjadi antara molekul-molekul gas atau cair dikontakkan dengan suatu permukaan padatan. Dalam penelitian ini, dirancang tabung alat uji adsorpsi metana serta sistem adsorpsi dan desorpsi yang diaplikasikan untuk tabung tersebut.

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The consumption of oil fuel, such as gasoline, solar and kerosene demand an increasing production of the oil fuel itself, so its availability are getting decreased every moment. Beside that, the combustion waste in motor vehicle produce air pollution which is one of the main factor in global warming. To overcome this problem, we should find a cleaner alternative energy with a higher octane value and still much available in the nature. One of this alternative energy is a natural gas with the main composition consist of methane (CH4). But to store this compressed natural gas (CNG), a 20 MPa of pressure vessel is needed. Adsorbed natural gas (ANG) is a solution to reduce the pressure in the tube of about 3.5 to 4 MPa by utilizing the process of adsorption using activated carbon. Adsorption is a physical phenomenon that occurs between the molecules of gas or liquid contacted with a solid surface. In this study it will be designed an adsorption and desorption system for methane as well as the pressure vessel used for testing it."

"Knowledge of the adsorption behavior especially at high pressure, has been long been important inprocesses involving high pressure gas adsorption such as: gas separation, gas storage, and CO;sequestration. However research on high pressure adsorption is considerably rare, also model that canaccurately represent high pressure gas adsorption. Accurate model which has a strong theoretical basecan improve model ability to predict gas adsorption when experimental data are not available. Therefore,the new model need to be developed to overcome the discrepancies of the existing model. In this study, weevaluate and further develop adsorption models based the Ono-Kondo (OIG theory to improve theirpredictive capabilities when dealing with near-critical and supercritical adsorption systems. The goal ofsuch developments is to facilitate the use of reliable computational frameworks for representingadsorption behavior, as well as improving our understanding of the phenomenon. The abilities of the two-parameter OK models to correlate accurately supercritical adsorption systems are demonstrated byrepresenting the adsorption data with 3. 6% AAD on average. The generalized OK model can also predictthe adsorption on activated carbon with 8% AAD. Furthermore, a high potential exist the model thatprovides reasonably accurate predictions for other gases adsorption isotherms based on adsorption datafor one gas at given temperature."

"The present Volume 4 of the successful monograh package “Multiphase flow dynamics”is devoted to selected chapters of the multiphase fluid dynamics that are important for practical applications but did not find place in the previous volumes. The state of the art of the turbulence modeling in multiphase flows is presented. As introduction, some basics of the single phase boundary layer theory including some important scales and flow oscillation characteristics in pipes and rod bundles are presented. Then the scales characterizing the dispersed flow systems are presented. The description of the turbulence is provided at different level of complexity: simple algebraic models for eddy viscosity, simple algebraic models based on the Boussinesq hypothesis, modification of the boundary layer share due to modification of the bulk turbulence, modification of the boundary layer share due to nucleate boiling. The role of the following forces on the mathematical description of turbulent flows is discussed: the lift force, the lubrication force in the wall boundary layer, and the dispersion force. A pragmatic generalization of the k-eps models for continuous velocity field is proposed containing flows in large volumes and flows in porous structures. A Methods of how to derive source and sinks terms for multiphase k-eps models is presented. A set of 13 single- and two phase benchmarks for verification of k-eps models in system computer codes are provided and reproduced with the IVA computer code as an example of the application of the theory. This methodology is intended to help other engineers and scientists to introduce this technology step-by-step in their own engineering practice.In many practical application gases are solved in liquids under given conditions, released under other conditions and therefore affecting technical processes for good of for bad. Useful information on the solubility of oxygen, nitrogen, hydrogen and carbon dioxide in water under large interval of pressures and temperatures is collected, and appropriate mathematical approximation functions are provided. In addition methods for the computation of the diffusion coefficients are described. With this information solution and dissolution dynamics in multiphase fluid flows can be analyzed. For this purpose the non-equilibrium absorption and release on bubble, droplet and film surfaces under different conditions is mathematically described. A systematic set of internally consistent state equations for diesel fuel gas and liquid valid in broad range of changing pressure and temperature is provided."