Engineering Commons^™

Towards An Understanding Of How Tube Inserts Mitigate Fouling In Heat Exchangers, B. Aquino, C. Derouin, G.T. Polley

Heat Exchanger Fouling and Cleaning VII

A number of studies undertaken by Total have measured the improvement that can be expected when TurbotalTM inserts are installed in heat exchangers. These studies have fully established that TurbotalTM both improve heat transfer coefficient and mitigate fouling. It has been found that fouling levels vary with application. Consequently, economics of installing inserts are difficult to quantify. Gains must be estimated through specific tests. A model that predicts fouling development solves this problem. In this paper first steps towards the understanding of how TurbotalTM limits the fouling rate are described. Authors suggest that the calculation of both pressure drop and …

Cleaning High-Speed Marine Separators With An Environmentally-Friendly Cip Agent, Ulf Nylén, Roger Andersson, Peter Forsberg

Heat Exchanger Fouling and Cleaning VII

The present contribution is devoted to the cleaning of high-speed marine separators employing the environmentally-friendly Cleaning In Place (CIP) agent Alpacon Multi Cip Super. For this particular study an Alfa Laval lube oil separator of type S831 on board the ship MS Isabella was dismantled prior to its first CIP treatment since installation and a few of the sludge-coated insert discs were taken as samples for laboratory experiments. Following assembly, the separator was cleaned according to a standard CIP protocol. Back in the laboratory, experiments mimicking the field CIP conditions verified the excellent cleaning results observed by visual inspection out …

Biofouling Control In Heat Exchangers Using High Voltage Capacitance Based Technology, R. Romo, M. M. Pitts, N. B. Handagama

Heat Exchanger Fouling and Cleaning VII

Biofouling in industrial heat exchangers and piping systems is common in water from all sources. Problems generated by biofouling such as corrosion, sludge deposition and scale formation have a costly impact on industrial equipment and productivity. This paper describes an electronic approach using High Voltage Capacitance Based technology (HVCB) to control biofouling in industrial heat exchangers, focusing upon biofilm removal and the prevention of biofilm formation. Four different application case studies are presented in this paper in which the HVCB technology was used to control biofouling. The applications include an evaporative cooling wall in a greenhouse in Oracle, Arizona; a …

Cleaning Monitoring Using Controlled Nano-Vibrations, A. Pereira, J. Mendes, L.F. Melo

Heat Exchanger Fouling and Cleaning VII

The monitoring of fouling and cleaning has become very important in order to optimize production cycles, to increase the quality of the final product and to reduce environmental impacts. The aim of the study here presented was to use the MSS – Mechatronic Surface Sensor, to detect the cleaning end-point of hair shampoo removal under different cleaning conditions. It was found that this new monitoring tool was able to clearly identify when the equipment was cleaned, producing different cleaning curves for different cleaning conditions.

Solving A Hydtrotreater Feed Filter Fouling Problem, X.A. Wu, K.H. Chung

Heat Exchanger Fouling and Cleaning VII

Feed filters were installed in Syncrude hydrotreater units to protect the catalyst beds from plugging by fine solids in the feed. Severe filter fouling occurred after a process flow sheet change. The root cause of fouling was revealed through a step-by-step scientific investigation. It was first confirmed that the fouling problem was related to a process flow sheet change that introduced a heavy vacuum gas oil (HVGO) stream into the coker combined gas oil (KCGO) stream prior to filtration. Characterization of the foulant and the feed indicated that the fouling reactions are likely oxidative polymerization. Iron naphthenate or naphthenic acid …

Electrochemical Impedance And Digital Image Methods To Detect Initial Deposition Of Microorganisms, H. Men, S. W. Mu, Z. W. Lu, Y. L. Chen, S.R. Yang, Y. P. Jia, S. X. Cao

Heat Exchanger Fouling and Cleaning VII

Microorganism in industrial cooling water can cause corrosion and biofouling. Electrochemical impedance method and digital image method (DIM) were used to detect quantitatively iron bacteria and heterotrophic bacteria. Microorganism growth and metabolism can change the impedance of culture medium. The detection time of impedance variation lie in the function relationship with the logarithm of bacteria concentration. 7-million-pixel CCD sensor was used to shoot the shape of microorganism in order to count the number. Compared with most probable number (MPN) method, the detection time of electrochemical impedance is shortened. The DIM reduces the bacteria counting time and the inaccuracy associated with …

Slag Monitoring System For Combustion Chambers Of Steam Boilers, J. Taler, D. Taler

Heat Exchanger Fouling and Cleaning VII

The computer based boiler performance system, presented in this paper, has been developed to provide a direct and quantitative assessment of furnace and convective surface cleanliness. Temperature, pressure and flow measurements and gas analysis data are used to perform heat transfer analysis in the boiler furnace and evaporator. Power boiler efficiency is calculated using an indirect method. The on-line calculation of the exit flue gas temperature in a combustion chamber allows for an on-line heat flow rate determination, which is transferred to the boiler evaporator. Based on the energy balance for the boiler evaporator, the superheated steam mass flow rate …

Acuta Enews July 2007, Vol. 36, No. 7

ACUTA Newsletters

ln This lssue

Meet the Board for 2007-08

From ACUTA Headquarters: Member Anniversaries............... Jeri A. Semer, CAE, Executive Director

Tech Talk: The Passing of Passwords................... Kevin Tanzillo, Dux PR

DC Update .................. Jeanne Jansenius, Sewanee, The University of the South

Check lt Out: RFls/RFPs, Job Postings, Press Releases

Board Report ................. Riny Ledgerwood, Son Diego State Univ., ACUTA Sec./Treasurer

FYI: Useful lnformation from the campus............... Student Monitor

Level 3 Completes lnternet2 Optical Network implementation

Member Sites to See

lnfo Links................... Randy Hayes, Univ. of Northern lowa

Terri Robinett Wins Room at the Conference

$5250,000 Emergency & Event Notification "Grants,, from …

Reliability Of Concrete Masonry Unit Walls Subjected To Explosive Loads, Christopher D. Eamon

Civil and Environmental Engineering Faculty Research Publications

This study discuses the development of a procedure that can be used to assess the reliability of concrete masonry unit infill walls subjected to personnel-delivered blast loads. Consideration is given to maintain reasonable computational effort for both the structural analysis and reliability models. Blast load and wall resistance models are developed based on experimental and analytical data, and resistance is evaluated with a large strain, large displacement transient dynamic finite element analysis. A sensitivity analysis is conducted to identify significant random variables and a reliability analysis conducted with a feasible level of computational effort. Reliability indices are estimated for two …

Engineering At San Jose State University, Summer 2007, San Jose State University, Charles W. Davidson College Of Engineering

Engineering at San Jose State University

No abstract provided.

Santa Clara Magazine, Volume 49 Number 1, Summer 2007, Santa Clara University

Santa Clara Magazine

8 - A CENTURY OF BRONCO BASKETBALL, By Jed Mettee and Steven Boyd Saum. Celebrating the first hundred seasons.

12 - A FAMILY SHOW By Steven Boyd Saum. Meet new men's basketball coach Kerry Keating.

14 - A SPACE THAT TALKS TO NATURE By Miriam Schulman. A team of SCU students aim to win the Department of Energy's Solar Decathlon. And save the planet.

19 - EPITAPH FOR THE JOURNEY A poem by Paul Mariani.

22 - THE BUZZ ABOUT SUSTAINABILITY By John Farnsworth. When we talk about "sustainability," what are we really talking about?

26 - THE GREEN TAX …

Supporting Lexical Ontology Learning By Relational Exploration, Sebastian Rudolph, Johanna Volker, Pascal Hitzler

Computer Science and Engineering Faculty Publications

Designing and refining ontologies becomes a tedious task, once the boundary to real-world-size knowledge bases has been crossed. Hence semi-automatic methods supporting those tasks will determine the future success of ontologies in practice. In this paper we describe a way for ontology creation and refinement by combining techniques from natural language processing (NLP) and formal concept analysis (FCA). We point out how synergy between those two fields can be established thereby overcoming each other’s shortcomings.

Solar 2007: Florida's Emergency Shelters Go Solar, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

Florida has its fair share of dangerous weather conditions including hurricanes, tornados and floods. Florida Legislature passed various laws and made revisions addressing disaster planning which required that the Department of Education, in consultation with school boards and county and state emergency management offices, develop design standards for public shelters to be incorporated into State Requirements for Educational Facilities.

Last year, Solar for Schools, a state program, provided funds to put photovoltaic systems on schools that are classified as shelters, adding a new dimension to the educational program. Middleton High School is an example of an application to power the …

The Gravity Data Ontology: Laying The Foundation For Workflow-Driven Ontologies, Ann Q. Gates, G. Randy Keller, Flor Salcedo, Paulo Pinheiro Da Silva, Leonardo Salayandia

Departmental Technical Reports (CS)

A workflow-driven ontology is an ontology that encodes discipline-specific knowledge in the form of concepts and relationships and that facilitates the composition of services to create products and derive data. Early work on the development of such an ontology resulted in the construction of a gravity data ontology and the categorization of concepts: "Data," "Method," and "Product." "Data" is further categorized as "Raw Data" and "Derived Data," e.g., reduced data. The relationships that are defined capture inputs to and outputs from methods, e.g., derived data and products are output from methods, as well as other associations that are related to …

Computer Simulation And Human Experiment On The Laplacian Electrocardiogram (Ecg), Ting Chen

Doctoral Dissertations

The electrocardiogram (ECG) provides useful global temporal assessment of cardiac activity, but has limited spatial capabilities. Laplacian electrocardiogram (LECG) and body surface Laplacian mapping (BSLM), improvements over ECG provides high spatiotemporal distributed information about cardiac electrical activation.

This project was divided into two parts: computer simulation and human experiment. In the computer simulation, a comparison of the performance of the tripolar and bipolar as well as spline LECG and BSLMs for localizing and imaging the cardiac electrical activation has been investigated. A simple planar surface model and a simplified eccentric heart-torso sphere-cylinder homogeneous volume conductor model were developed. Multiple dipoles …

Gen Ms 22 Hayden Anderson Papers Finding Aid, Daniel Draper

Search the General Manuscript Collection Finding Aids

Description:

Hayden L. Anderson was a prominent Maine educator and Maine historian. He graduated from Gorham Normal School in 1925, and subsequently earned degrees from Boston University and Bates College, as well as doing graduate work at Harvard University. He served as principal and superintendent in schools in central and northern Maine, and as Dean of Instruction at Farmington State College. He also worked in the State Department of Education and served on the Board of Trustees of the University of Maine. He was a student of local history, editing the bicentennial history of Litchfield, Litchfield Yesteryears, and writing a …

Cover Page, Hans Müller-Steinhagen, M. Reza Malayeri, Paul Watkinson

Heat Exchanger Fouling and Cleaning VII

No abstract provided.

Free Alkali-Index For Optimizing The Fuel Mixture In Biomass Co-Firing, T.E. Blomberg

Heat Exchanger Fouling and Cleaning VII

Co-firing biomass with fossil fuels provides a cheap and efficient reduction of the CO2 emissions in electricity generation. One of the main challenges in co-firing is the increased fouling and corrosion rates of the heat transfer surfaces when biomass is added to the fuel mixture. Optimization of the fuel mixture from the fouling and corrosion point of view would be an easier task, if some fuel properties would provide correlation with the fouling and corrosion rates. Currently there is no clear understanding of the most useful fuel indices. The fouling indices used in coal firing have proved to be less …

The Science Of Cleaning Of Dairy Fouling Layers, R. Mercadé-Prieto,, W.R. Paterson, D.I. Wilson

Heat Exchanger Fouling and Cleaning VII

The science underlying the removal of dairy fouling layers, and particularly the dissolution of proteinaceous deposits in alkaline solution, is relatively poorly understood even though this is a critical feature of many cleaning-in-place operations. We report key results from a series of investigations on heat-induced gels of β- lactoglobulin, the primary whey protein component in milk and whey foulant. These model systems were used to elucidate the reaction behaviour of gels and aggregates whereby the proteinaceous material is converted to a softer, swollen form that can then be removed by fluid shear or diffusion. We show that several features, such …

Study Of An Organic Crystallization Fouling Problem, Hirofumi Inokuchi, Mitsutaka Nakamura, Yoshio Koga

Heat Exchanger Fouling and Cleaning VII

One of the aromatic compound plants in Mitsubishi Chemical Corporation has a heavy crystallization fouling problem. We have been studying the crystallization process using the shell and tube heat-exchanger. In order to solve our fouling problem of the heat exchanger, we developed the specified evaluation equipment (crystallization fouling simulator : CFS) which consists of a single tube heatexchanger (Tube size: ID=10.3mm Length=500mm). The result of the modeling for describing the crystallization fouling rate and the countermeasure of the fouling problem are discussed in this work. It can be possible to describe the fouling rate as one equation which has two …

Bacterial And Protein Adhesion On Ni-P-Ptfe Coated Surfaces, Q. Zhao, C. Liu, Y. Liu, S. Wang

Heat Exchanger Fouling and Cleaning VII

The adhesion of bacteria and proteins on the surfaces of heat exchangers and food processing equipment has been recognized as a widespread problem. Biofouling not only reduces heat transfer performance significantly, but also causes considerable pressure drop, calling for higher pumping requirements. Biofouling also present a considerable hygiene risk in the food industry. It would be much more desirable if surfaces with an inherently lower stickability for biofouling could be developed. In this paper, stainless steel 304 plates were modified by electroless plating Ni-P and small amounts of PTFE. The experimental results showed that the surface free energy of the …

Evaluation Of Heat Transfer Boundary Conditions For Cfd Modeling Of A 3d Plate Heat Exchanger Geometry, T.M. Pääkkönen, M. Riihimäki, R. Ylönen, E. Muurinen, C.J. Simonson, R.L. Keiski

Heat Exchanger Fouling and Cleaning VII

In this paper fluid flow and heat transfer are modeled in a corrugated 3D plate heat exchanger geometry with a commercial computational fluid dynamics (CFD) program, Fluent 6.1.22 (Fluent Inc., Lebanon), in order to find out the most realistic heat transfer boundary conditions for a plate heat exchanger. The built-in boundary conditions of Fluent available for this case are Heat flux, Convection and Constant wall temperature. The CFD models are verified with correlations and experimental data obtained by a flat plate test equipment of which parameters can be calculated analytically. Deficiencies are found in all the built-in heat transfer boundary …

Metallic Micro Heat Exchangers: Properties, Applications And Long Term Stability, J.J. Brandner, W. Benzinger, U. Schygulla, S. Zimmermann, K. Schubert

Heat Exchanger Fouling and Cleaning VII

Micro heat exchangers, which until recently have been implemented only at laboratory scale, are now being available for industrial applications. They are well known for their superior heat transfer properties due to the large surface-to-volume ratio. But there are little data available on the long term stability of these devices. In this paper application several application examples for micro heat exchangers made of stainless steel are presented. The devices consist of stainless steel foils providing numerous micro channels generated by mechanical micromachining or wet chemical etching. A number of the foils are arranged in a specific way and bonded together. …

Fouling Monitoring And Cleaning Optimisation In A Heat Exchanger Network Of A Crude Distillation Unit, Andrea Heins, Ramón Veiga, Carlos Ruiz, Andrés Riera

Heat Exchanger Fouling and Cleaning VII

Fouling in preheat networks of crude distillation units (CDU) plays an important role in energy consumption. In this work a procedure to monitor the performance of the heat exchanger network (HEN) and to optimize the cleaning strategies is presented. The procedure is based on a rigorous simulation of the HEN using Hysys (from Aspen Technology). The simulation is used to estimate the service overall heat transfer coefficient with real operational data acquired from the unit’s Plant Information System (PI). The clean overall heat transfer coefficient is calculated for each one of the individual heat exchangers with a rigorous simulation using …

Cfd And Neural Network-Based Expert System For The Supervision Of Boilers And Furnaces, Hugo Calisto, Nelson Martins, Naim Afgan

Heat Exchanger Fouling and Cleaning VII

CFD (Computational Fluid Dynamics) tools were used to build a "virtual" furnace, validated with experimental data. This model was used to simulate both normal and “faulty” behaviours, regarding parameters such as energy conversion efficiency, steam leakage and fouling. A database was developed comprising normal situations and simulated fault sets, characterized by virtual sensor outputs used in the evaluation of diagnostic parameters patterns to be processed and recognized by the diagnostic system. The database was processed using Neural Networks, with satisfactory results even in their most simple form (backpropagation networks) trained using standard algorithms. Pattern recognition was thus performed, identifying root …

Blowout Penstemon (Penstemon Haydenil) Endangered Species, James Stubbendieck, Kay Lynn Kottas

Nebraska Department of Transportation: Research Reports

No abstract provided.

Global-Change Scenarios: Their Development And Use, Edward Parson, Virginia Burkett, Karen Fisher-Vanden, David Keith, Linda Mearns, Hugh Pitcher, Cynthia Rosenzweig, Mort Webster

United States Department of Energy: Publications

A scenario is a description of potential future conditions produced to inform decision-making under uncertainty. Scenarios can help inform decisions that involve high stakes and poorly characterized uncertainty, which may thwart other, conventional forms of analysis or decision support. Originally developed to study military and security problems, scenarios are now widely used for strategic planning and assessment in businesses and other organizations, and increasingly to inform planning, analysis, and decision-making for environmental issues, including climate change.
Scenarios can serve many purposes. They can help inform specific decisions, or can provide inputs to assessments, models, or other decision-support activities when these …

Scenarios Of Greenhouse Gas Emissions And Atmospheric Concentrations, Leon Clarke, James Edmonds, Henry Jacoby, Hugh Pitcher, John Reilly, Richard Richels

United States Department of Energy: Publications

This and a companion report constitute one of twenty-one Synthesis and Assessment Products called for in the Strategic Plan for the U.S. Climate Change Science Program. These studies are structured to provide high-level, integrated research results on important science issues with a particular focus on questions raised by decision-makers on dimensions of climate change directly relevant to the U.S. One element of the CCSP’s strategic vision is to provide decision support tools for differentiating and evaluating response strategies. Scenario-based analysis is one such tool. The scenarios in this report explore the implications of alternative stabilization levels of anthropogenic greenhouse …

Selection Of The Spraying Technologies For Over-Coating Of Metal-Stampings With Thermo-Plastics For Use In Direct-Adhesion Polymer Metal Hybrid Load-Bearing Components, M. Grujicic, V. Sellappan, Laine Mears, X. Xuan, Norbert Seyr, Marc Erdmann, Jochen Holzleitner

Publications

The suitability of various polymer-powder spraying technologies for coating of metal-stampings used in polymer metal hybrid (PMH) load-bearing automotive-component applications is considered. The suitability of the spraying technologies is assessed with respect to a need for metal-stamping surface preparation/treatment, their ability to deposit the polymeric material without significant material degradation, the ability to selectively overcoat the metal-stamping, the resulting magnitude of the polymer-to-metal adhesion strength, durability of the polymer/metal bond with respect to prolonged exposure to high-temperature/high-humidity and mechanical/thermal fatigue service conditions, and compatibility with the automotive body-in-white (BIW) manufacturing process chain. The analysis revealed that while each …

Development And Analysis Of An Internet Browsing Utilizing The Overscan Technique For Persons With Physical Disabilities, Patrick Paul Clerkin

Doctoral Dissertations

Persons with a severe disability often use scanning as an indirect selection technique for operating augmentative and alternative communication aids and computer access. For information that can be organized in advance, including lists of communication elements such as words and phrases, users often employ rate enhancing scanning methods like the row-column scanning technique. However, row-column scanning requires selection elements to be grouped into defined rows and columns, and therefore does not work well with Internet browsing due to the non-grouped layout of HTML pages.

This work attempts to develop an improved scanning technique for Internet browsing by designing interfaces to …