Engineering Commons^™

My Cv 2010, Sandip K. Lahiri

Dr. Sandip Kumar Lahiri

No abstract provided.

Development Of Support Vector Regression Based Soft Sensor, Sunil Kumar Sawke Mr.

Sunil Kumar Sawke

This article describes a systematic approach to the inferential measurement developments of carbonate and bicarbonate ratio, using support vector regression (SVR) analysis. Given historic process data, a simple SVR based soft sensor model is found capable of identifying and capturing the cause and effect relationship between operating variables (model input) and QC variables so that the final correlation and regression coefficient was understood by process engineers.

Fractional Factorial Design Optimization Of Nontraditional Completion Fluid For Perforation With Underbalance, Abdul Aziz Abdul Raman

Abdul Aziz Abdul Raman

Optimal well performance is always associated with the creation of a clean and undamaged connection between wellbore and reservoir. However, it is apparent that the use of shaped-charge perforating tends to produce perforation-induced formation damage. This damage impairs fluid flow and decreases well productivity. To minimize and eliminate this damage, underbalance perforating should be considered. Underbalance perforating has been considered as one of the best means of providing a transient surge flow for tunnel cleanup. This paper introduces the formulation of super lightweight completion to achieve underbalance condition. The formulation was optimized using fractional factorial design. The result indicates that …

Leaching Mechanism Of Semiconducting Minerals, Fathi Habashi

Fathi Habashi

The mechanism of leaching of semiconducting minerals such as PbS, ZnS, UO2, etc., has been the subject of intensive speculation by hydrometallurgists in the early 1950s. The electrochemical mechanism proposed in 1970 by the author in volume 2 of his Principles of Extractive Metallurgy avoids the assumption of forming intermediate complexes that cannot be isolated or identified.

Potassium Hydroxide Catalyst Supported On Palm Shell Activated Carbon For Transesterification Of Palm Oil, Abdul Aziz Abdul Raman

Abdul Aziz Abdul Raman

In this study, potassium hydroxide catalyst supported on palm shell activated carbon was developed for transesterification of palm oil. The Central Composite Design (CCD) of the Response Surface Methodology (RSM) was employed to investigate the effects of reaction temperature, catalyst loading and methanol to oil molar ratio on the production of biodiesel using activated carbon supported catalyst. The highest yield was obtained at 64.1 °C reaction temperature, 30.3 wt.% catalyst loading and 24:1 methanol to oil molar ratio. The physical and chemical properties of the produced biodiesel met the standard specifications. This study proves that activated carbon supported potassium hydroxide …

Regulating Factors In Anthocyanin Biosynthesis, Gregory Keith Bartley Jr.

Gregory Keith Bartley Jr.

No abstract provided.

A Short-Distance Integral-Balance Solution To A Strong Subdiffusion Equation: A Weak Power-Law Profile, Jordan Hristov

Jordan Hristov

The work presents an integral solution of the time-fractional subdiffusion through a preliminary defined profile with unknown coefficients and the concept of penetration layer well known from the heat diffusion The profile satisfies the boundary conditions imposed at the boundary of the boundary layer in a weak form that allows its coefficients to be expressed through the boundary layer depth as unique parameter describing the profile. The technique is demonstrated by a solution of a time fractional subdiffusion equation in rectilinear 1-D conditions.

Some Features Of The Concentration Oscillations In The Phenylacetylene Oxidative Carbonylation Reaction (In Russian), Sergey N. Gorodsky

Sergey N. Gorodsky

Some modes of concentration oscillations in the homogeneous system KI-PdI2-CO-O2-CH3OH are described in this paper.

High Quality Biodiesel And Its Diesel Engine Application: A Review, Abdul Aziz Abdul Raman

Abdul Aziz Abdul Raman

The continuous increasing demand for energy and the diminishing tendency of petroleum resources has led to the search for alternative renewable and sustainable fuel. Biodiesel is best substitute for petro-diesel and also most advantageous over petro-diesel for its environmental friendliness. The quality of biodiesel fuel was found to be significant for its successful use on compression ignition engines and subsequent replacement of non-renewable fossil fuels. Conventional biodiesel separation and purification technologies were noticed to yield lower quality biodiesel fuel with resultant excessive energy and water consumptions. Membrane technology showed more potential for effective and efficient separation and purification of biodiesel. …

Energetyka Niskoemisyjna, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.

Bacterial Chemotaxis In Porous Media: Theory Derivation And Comparison With Experiments, Francisco J. Valdes-Parada, Mark L. Porter, Brian D. Wood

Francisco J. Valdes-Parada

Chemotaxis is the movement of organisms toward or away from the concentration gradient of a chemical species. Microbial chemotaxis has been shown to significantly increase contaminant degradation in subsurface environments with respect to traditional methods such as pump-and-treat. This type of transport phenomena often involves diffusion and convection along several scales. In this work we use the method of volume averaging to upscale the governing equations for in situ bioremediation by bacterial chemotaxis. The results are effective medium mass balance equations for both the bacteria and the chemical attractant. These equations are expressed in terms of average transport coefficients, which …

Hydroxyl-Terminated Poly(Urethane Acrylate) As A Soft Liner In Dental Applications: Synthesis And Characterization, Selda Keskin

ABSTRACT: Hydroxyl-terminated poly(urethane acrylate) s were synthesized for use in biomedical applications. Acrylate end capping via an interesterification reaction was successfully achieved with methacryloyl chloride addition to the hydroxyl ends of the polyurethane at low temperatures. 2,4-Toluene diisocyanate, 1,6-hexane diisocyanate, and methylene diphenyl diisocyanate were used as diisocyanates for urethane synthesis, and they were end-capped with methyl methacrylate and hydroxyethyl methacrylate. The nature of the monomers that we used had an effect on the thermal and morphological properties that were interpreted in terms of the level of hydrogen bonding and the degree of phase separation. The synthesized polymers were characterized …

Interpretation Of Closure Variables In Upscaling, Francisco J. Valdes-Parada, Mark L. Porter, Brian D. Wood

Francisco J. Valdes-Parada

In many engineering applications, it is common to nd systems that involve transport at several scales. Despite the increasing computational capabilities, it is still not feasible to model a complete macroscopic system by direct numerical simulations at the microscale. Actually, it is more convenient to derive models at an intermediate level of scale between the microscale and the macroscale; this is the average scale. The derivation of models at this scale can be carried out by means of the method of volume averaging. The results from this method are averaged transport equations expressed in terms of eective medium coecients that …

One-Domain Approach For Heat Transfer At The Fluid-Porous Medium Inter-Region, Francisco J. Valdes-Parada, Carlos G. Aguilar-Madera, Benoît Goyeau, J. Alberto Ochoa-Tapia

Francisco J. Valdes-Parada

The modeling of transport phenomena in the zone of rapid changes between a fluid and a porous medium (i.e., the interregion) can be carried out using two distinctive approaches. The first one, generally called the one-domain approach, describes transport phenomena in the whole fluid-porous system using averaged macroscopic conservation equations including spatially dependent effective properties. These coefficients reduce to their respective constant values in the homogeneous fluid and porous regions of the system. As an alternative, the two-domain approach uses the transport equations with constant coefficients in the entire domain of each region, including the zone of drastic changes. To …

Derivation Of Complete Jump Boundary Conditions Between Homogeneous Media, Francisco J. Valdes-Parada, Benoît Goyeau, J. Alberto Ochoa-Tapia

Francisco J. Valdes-Parada

The modeling of transport phenomena between homogeneous regions requires the derivation of jump boundary conditions. These conditions account for the rapid spatial variations of the transport properties taking place near the dividing surface of the media. There has been a long debate in the literature about whether the discontinuity should apply to the fields (e.g., velocity, temperature, concentration) or to their fluxes. In this work, a general methodology giving rise to jump conditions for both the fields and the fluxes is proposed. This method, besides using a microscopic closure, introduces macroscopic deviation fields that lead to closure schemes for both …

Heat-Balance Integral To Fractional (Half-Time) Heat Diffusion Sub-Model, Jordan Hristov

Jordan Hristov

The fractional (half-time) sub-model of the heat diffusion equation, known as Dirac-like evolution diffusion equation has been solved by the heat-balance integral method and a parabolic pro file with unspecified exponent. The fractional heat-balance integral method has been tested with two classic examples: fixed temperature and fixed flux at the boundary. The heat-balance technique allows easily the convolution integral of the fractional half-time derivative to be solved as a convolution of the time-independent approximating function. The fractional sub-model provides an artificial boundary condition at the boundary that closes the set of the equations required to express all parameters of the …

Study Of Nano Structure Mn/Alumina Catalyst Deactivation Through Catalytic Oxidation Of O-Vocs, Hosein Afshary

Hosein Afshary

the deactivation and selectivity behavior of nanostructure Mn/γ-Al2O3 catalyst in catalytic oxidation of an O-VOC (isopropanol) was studied. The polluted air was simulated and the catalyst was tested in the course of 50-h time-on-stream. Characterization of fresh and used catalysts was done using FT-IR, XRD, SEM and EDS methods. Comparing the testing results of this catalyst and that of the industrial Pt/Al2O3 catalyst showed that prepared catalyst can be suitable for substitution with the expensive pt/Al2O3 catalyst in environmental applications.

Modelo Aproximado Del Coeficiente De Dispersión En Medios Porosos, Francisco J. Valdes-Parada, Helen D, Lugo-Méndez, J. Alberto Ochoa-Tapia

Francisco J. Valdes-Parada

En este trabajo, se utiliza el método del promedio volumétrico para la predicción del coeficiente efectivo de dispersión y la teoría de las funciones de Green para encontrar una solución analítica aproximada. Como simplificación de la celda representativa del medio poroso homogéneo, se usó la celda de Chang, imponiendo la condición de flujo reptante. Para corroborar los resultados se determinó numéricamente el coeficiente efectivo, en celdas unitarias periódicas usando el programa comercial basado en el método de de elemento finito COMSOL Multiphysics. El coeficiente efectivo de dispersión analítico obtenido en este trabajo presenta una tendencia análoga al numérico, además de …

Diseño De Una Parrilla Para La Reducción De Pérdidas De Energía En Estufas Convencionales, Francisco J. Valdes-Parada, Victor Castillo-Jimenez, Alberto Gabino-Zamora, Armando Astudillo-Velázquez

Francisco J. Valdes-Parada

Las estufas de gas convencionales tienen, por lo general, pérdidas considerables de energía alrededor del quemador, lo que disminuye su eficiencia e incrementa el consumo de recursos. Para atender este problema, en este trabajo se propone concentrar la mayor parte del calor hacia una sola región, para poder obtener la mayor cantidad de energía sin tener que suministrar más combustible y de esta manera aumentar la eficiencia de estufas convencionales. Para ello, se construyó un prototipo experimental a partir de cálculos de diseño teóricos. Con el prototipo ahorrador de energía se consiguió un ahorro hasta del 40% del consumo de …

Análisis De La Transferencia De Calor En Azoteas Verdes, Francisco J. Valdes-Parada, Verónica Freyre-Fonseca

Francisco J. Valdes-Parada

El problema de las islas urbanas de calor contribuye a los drásticos cambios climáticos que se sufren en ciudades densamente pobladas. Para atender este problema se tienen diversas alternativas, entre las cuales se contempla incorporar zonas verdes (e.g., paredes y azoteas verdes) en edificaciones que contrarresten los efectos de calentamiento excesivo. En este trabajo se estudia la transferencia de calor en edificaciones típicas de la ciudad de México utilizando diferentes configuraciones de zonas verdes. Los resultados muestran que el utilizar azoteas verdes tiene un efecto estabilizador en los perfiles locales de temperatura; sin embargo a nivel de toda una edificación, …

Modelado De Un Reactor Solar Para El Cracking De Metano, Francisco J. Valdes-Parada, Hernando Romero-Paredes

Francisco J. Valdes-Parada

En este trabajo se realiza el modelado de un reactor solar tubular con una capacidad de hasta 15 kW para la disociación térmica del metano. El reactor está compuesto por un tubo de grafito inmerso en una cavidad también de grafito que juega el papel de receptor del flujo solar concentrado. El objetivo de este trabajo es evaluar los perfiles de velocidad, de concentración y temperatura a lo largo del reactor en función de la concentración y el flujo de gas a la entrada del reactor. Con lo cual ha sido posible evidenciar algunos fenómenos poco discutidos durante la experimentación. …

Sobre La Suposición De Estado Cuasiestacionario En El Transporte De Calor De Una Ventana Doble, Francisco J. Valdes-Parada, Erika K. Flores-Romero, Geovanni Hernandez-Luna, Erick A. Aguilera-Romero

Francisco J. Valdes-Parada

Es sabido que la mayoría de las edificaciones modernas transfieren la mayor parte de la energía acumulada a través de ventanas. Por ello, en la medida en que se tengan modelos confiables para el transporte de calor a través de estos sistemas, se contará con mejores diseños que tienen una relación directa con el confort, ambiente y gasto energético de edificaciones. El modelado de la transferencia de calor en ventanas dobles suele llevarse a cabo considerando únicamente sus cristales y el aire atrapado entre ellos. Sin embargo, la temperatura del interior es, a su vez, una función del tiempo y …

Escalamiento De Dispersión De Contaminantes En La Ciudad De México, Francisco J. Valdes-Parada, J. Ruben Varela-Ham

Francisco J. Valdes-Parada

En días hábiles, la actividad vehicular más intensa en calles y avenidas de la ciudad de México se inicia a las 6:00 hs y se prolonga por aproximadamente 3 ó 4 horas. En ese periodo, la capa de mezclado permanece relativamente quieta y expuesta a recibir una carga importante de contaminantes producto de emisiones vehiculares. En esas condiciones de ausencia de movimientos atmosféricos verticales y horizontales, y de intensa actividad contaminante, adquieren importancia los procesos de dispersión que ocurren en la horizontal y a nivel del suelo.

En este trabajo se lleva a cabo un proceso de promediado de las …

Integral Formulation For The Solution Of Closure Problems In Upscaling Processes, Francisco J. Valdes-Parada

Francisco J. Valdes-Parada

The derivation of transport models at macroscopic scales can be carried out using upscaling techniques such as the method of volume averaging. This upscaling technique consists on averaging the transport equations that describe phenomena at the microscale. The result is the so-called eective medium models, which are expressed in terms of eective coecients that can be computed from the solution of the corresponding closure problems. In this work, we present an integral formulation based on Green's functions to carry out the formal solution of closure problems. This methodology not only provides a physical interpretation of the closure variables, but it …

Conference Proceedings 3rd International Scientific Conference On “Energy Systems With It” At Alvsjö Fair In Association With Energitinget March 16-17 2010, Dr. Erik Dahlquist, Dr. Jenny Palm

Dr. Erik Dahlquist

2010 “The Energiting” is performed for the 12th time. The International Scientific conference is arranged for the 3rd time. The organisers are Swedish Energy Agency, Mälardalen University and the Research School for Energy Systems with LiU, KTH, UU and CTH. The first topic will be “Energy systems” covering use of renewable energy sources, energy conversion and process efficiency improvement with new technologies, as well as societal aspects of the introduction of new technologies. The second topic is “Energy and IT”. This covers energy and load management, interaction between production, distribution and “consumption”, usage of data for decision support and control, …

My Phd Thesis : Study On Slurry Flow Modelling In Pipeline, Sandip K. Lahiri

Dr. Sandip Kumar Lahiri

Many large slurry pipelines were built and operating around the world. Pipeline transport is considered economical and environment friendly as compared to rail and road transport. To design the pipelines and its associated facilities (pumps etc) designers need accurate information regarding pressure drop, hold up, critical velocity, flow regimes etc at the early design phase. Also the operating engineers need to know accurately the critical velocity so that he can adjust the slurry flow to have a minimum pressure drop to ensure minimum operating cost. Such flows are complex and presently very little known about the two-phase interaction of solid …

Quantitative Risk Assessment For The Transport Of Ammonia By Rail, Abdul Aziz Abdul Raman

Abdul Aziz Abdul Raman

Risk assessments are considered to be an essential tool in ensuring the safety of engineering projects. The benefits of using risks assessments have prompted its acceptance in the safety legislation for a number of industries. The use of quantitative risk assessment for rail transportation of hazardous materials has gained more attention in recent years, because the amount of the transported hazardous materials is large, and the transportation route often passes through populated areas, such as cities. In this study, the risk for the ammonia transportation by rail in Malaysia was conducted by combining the results from a previous failure frequency …

Homotopy Perturbation Algorithm Using Laplace Transformation, Mohammad Madani, Mahdi Fathizade

Mohammad Madani

In this paper, a combinatory method of the Laplace transform and the homotopy perturbation method is proposed to solve non-homogeneous partial differential equations with variable coefficients. The obtained approximate solutions are compared with exact solutions and those obtained by other analytical methods, showing reliability of the present method.

Metals: Typical And Less Typical, Transition And Inner Transition, Fathi Habashi

Fathi Habashi

While most chemists agree on what is a metal and what is a non-metal there is a disagreement with respect to what is a metalloid and what is a transition metal. It is believed that this problem can be solved if two new terms are adopted: typical and less typical metals. These new terms will also help reconcile the European Periodic Table versus the North American regarding numbering of groups as well as the IUPAC numbering which could be as well abandoned in favour of group names as will be shown in the manuscript.

Phosphate Industry And The Radon Problem, Fathi Habashi

Fathi Habashi

The problem of radon generated during the treatment of phosphate rock by sulfuric acid to produce fertilizers can be solved by using nitric acid. In this case radium, which is the source of radon, goes into solution and can be precipitated by a controlled method and safely disposed of. A variety of options are discussed. Text in Farsi with English translation.