Loading...
Search for:
gas-flow
0.011 seconds
Total 43 records
Predictive analytics for fault reasoning in gas flow control facility: A hybrid fuzzy theory and expert system approach
, Article Journal of Loss Prevention in the Process Industries ; Volume 77 , 2022 ; 09504230 (ISSN) ; Nourian, R ; Mousavi, S. M ; Seyed Alizadeh, S. M ; Memarpour, M ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Gas pressure reduction stations are essential in energy distribution networks because even a minor failure of these systems causes disruptive consumer problems. This study aims to introduce and implement a new knowledge-based platform that uses the synthesized expert's opinions to improve gas pressure control facilities. Given the record of failure of gas transmission system components and the data's uncertain nature, a new fuzzy expert system is developed that takes advantage of the object-oriented programming paradigm to analyze failure modes and conditions. The artificial intelligent model is designed in C# programming language, and a user-friendly interface is developed for ease of...
Mathematical modeling of a slurry reactor for DME direct synthesis from syngas
, Article Journal of Natural Gas Chemistry ; Volume 21, Issue 2 , March , 2012 , Pages 148-157 ; 10039953 (ISSN) ; Kazemeini, M ; Fattahi, M ; Sharif University of Technology
2012
Abstract
In this paper, an axial dispersion mathematical model is developed to simulate a three-phase slurry bubble column reactor for direct synthesis of dimethyl ether (DME) from syngas. This large-scale reactor is modeled using mass and energy balances, catalyst sedimentation and single-bubble as well as two-bubbles class flow hydrodynamics. A comparison between the two hydrodynamic models through pilot plant experimental data from the literature shows that heterogeneous two-bubbles flow model is in better agreement with the experimental data than homogeneous single-bubble gas flow model. Also, by investigating the heterogeneous gas flow and axial dispersion model for small bubbles as well as the...
The effect of substrate surface roughness on ZnO nanostructures growth
, Article Applied Surface Science ; Volume 257, Issue 8 , February , 2011 , Pages 3291-3297 ; 01694332 (ISSN) ; Sangpour, P ; Khademi, A ; Moshfegh, A. Z ; Sharif University of Technology
2011
Abstract
The ZnO nanowires have been synthesized using vapor-liquid-solid (VLS) process on Au catalyst thin film deposited on different substrates including Si(1 0 0), epi-Si(1 0 0), quartz and alumina. The influence of surface roughness of different substrates and two different environments (Ar + H2 and N2) on formation of ZnO nanostructures was investigated. According to AFM observations, the degree of surface roughness of the different substrates is an important factor to form Au islands for growing ZnO nanostructures (nanowires and nanobelts) with different diameters and lengths. Si substrate (without epi-taxy layer) was found that is the best substrate among Si (with epi-taxy layer), alumina and...