Tutorial : Cyclepad - Tutorial , analysis, application, etc.

Using CyclePad, setting up such a cycle is actually very simple, but it requires that we know some of the basic facts and typical assumptions that apply to the cycle. We will examine a typical Rankine cycle problem and note the assumptions necessary to find the problem's solution, many of which will not be stated explicitly in the problem.

This documentation is explaining how to setting an explicit state of rankine cycle. And it covers ideal , reheat and regenerative cycle problems.

Download Tutorial :
RANKINE.PDF

Download Cyclepad application Journals/documentations :
- Teaching Rankine cycle by using an intelligent computer-aided design (PDF)
- Comparison between traditional and web-based interactive manuals ...(PDF)
- Examining Staged Enhancements for Thermodynamic Cycles to Improve Performance using an Intelligent Instruction Software (PDF)
- Rapid Authoring of Intelligent Tutors
- Laboratory Manual MECH 351 Thermodynamics II
- Building an Articulate Educational Software

From Amazone :
- Thermodynamic Cycles: Computer-Aided Design And Optimization
- Intelligent Computer Based Engineering Thermodynamics and Cycle Analysis
- Computer Aided Chemical Thermodynamics of Gases and Liquids: Theory Models and Programs
- Computer Aided Design in Composite Material Technology: Proceedings of the International Conference, Southampton 1988



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Tutorial : FLUENT - SIMULATING A MIXING ELBOW (2D)

This tutorial is further process from Tutorial : GAMBIT - MODELING A MIXING ELBOW . This tutorial illustrates the setup and solution of the two-dimensional turbulent fluid flow and heat transfer in a mixing junction. The mixing elbow configuration is encountered in piping systems in power plants and process industries.

It is often important to predict the flow field and temperature field in the neighborhood of the mixing region in order to properly design the location of inlet pipes.In this tutorial you will learn how to:

• Read an existing grid file into FLUENT
• Use mixed units to define the geometry and fluid properties
• Set material properties and boundary conditions for a turbulent forced convection problem
• Initiate the calculation with residual plotting
• Calculate a solution using the segregated solver
• Examine the flow and temperature fields using graphics
• Enable the second-order discretization scheme for improved prediction of temperature
• Adapt the grid based on the temperature gradient to further improve the
prediction of temperature

Related Posts:
- Tutorial : GAMBIT - MODELING A MIXING ELBOW (2D)

DOWNLOAD TUTORIAL:
FLUENT TUT01.PDF


Another Reading :
Computational Fluid Dynamics: Fluent, Inc., Computational Fluid Dynamics, Muscl Scheme, Flux Limiter, Lattice Boltzmann Methods

A study in computational fluid dynamics for application to the understanding of commercial software

The trends in CFD are continuous, dynamic, and real: a variety of new computational fluid dynamics (CFD) software packages are just a mouse click away ... article from: Automotive Design & Production


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Tutorial : GAMBIT - MODELING A COMBUSTION CHAMBER (3-D)

In this tutorial, you will create the geometry for a burner using a top-down geometry construction method in GAMBIT (creating a volume using solids). You will then mesh the burner geometry with an unstructured hexahedral mesh.

In this tutorial you will learn how to:
• Move a volume
• Subtract one volume from another
• Shade a volume
• Intersect two volumes
• Blend the edges of a volume
• Create a volume using the sweep face option
• Prepare the mesh to be read into FLUENT 5/6 

In this tutorial, you will create a combustion chamber geometry using the “top-down” construction method. You will create volumes (in this case, bricks and cylinders) and use Boolean operations to unite, intersect, and subtract these volumes to obtain the basic geometry. Finally, using the “blend” command, you will round off some edges to complete the geometry creation.

For this model, it is not possible to simply pick the geometry and mesh the entire domain with hexahedral elements, because the Cooper tool (which you will be using in this tutorial) requires two groups of faces, one group topologically parallel to a sweep path, and the other group topologically perpendicular. However, the rounded (blended) edges fit in neither group. See the GAMBIT Modeling Guide for a more detailed description of the Cooper tool. You need to decompose the geometry into portions that can be meshed using the Cooper tool. There are several ways to decompose geometry in GAMBIT. In this example, you will use a method whereby portions of the volume around the blend are split off from the main volume.

The problem to be considered is shown schematically in Figure above. The geometry consists of a simplified fuel injection nozzle that feeds into a combustion chamber. You will only model one quarter of the burner geometry in this tutorial, because of the symmetry of the geometry. The nozzle consists of two concentric pipes with radii of 4 units and 10 units respectively. The edges of the combustion chamber are blended on the wall next to the nozzle.

DOWNLOAD TUTORIAL
TUTORIAL GAMBIT 04


- Experimental studies of incineration in a cylindrical combustion chamber
- Design Engineering Challenges and Solutions of Kistler Automotive Combustion Pressure Sensors, Water-cooled Sensors, Piezoelectric Sensors, the Crank Angle ... System, and the Sensor Calibrarion Process
- Fuels of Opportunity: Characteristics and Uses in Combustion Systems


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Software : CyclePad, construct and learn about thermodynamic cycles

This is an old software but this is very useful. Through using CyclePad I can build and practice my design skills and learn how to reason about thermodynamic cycles. A thermodynamic cycle is a collection of components which either takes in heat and produces energy, or takes in work and produces some transfer of heat, perhaps as a refrigerator or as a heat pump. Examples of thermodynamic cycles include power plants, refrigerators, propulsion plants, and engines. CyclePad helps you:

• Specify the structure of your design , in terms of the parts of the cycle and how they are connected together.
• Analyze your design, by figuring out the consequences of assumptions you make about it. Such assumptions include numerical values, e.g. operating temperatures and pressures, and modeling assumptions, e.g., whether or not to consider a turbine as isentropic.
• Perform sensitivity analyses to understand how different choices of your design contribute to its performance. For example, CyclePad can figure out how the efficiency of a system changes as a function of other parameters, such as a turbine inlet temperature.

CyclePad is the first articulate virtual laboratory the Qualitative Reasoning Group has implemented. CyclePad enables students to construct and analyze a wide variety of thermodynamic cycles. A hypertext explanation facility provides the student with access to the chain of reasoning underlying the derivation of each value. CyclePad is currently being field-tested in undergraduate engineering classes at Northwestern University, The U.S. Naval Academy, and Oxford University.

CyclePad performs steady-state analyses of both open and closed cycles.Steady-state analyses provide the kind of initial guidance needed in conceptual design, because in the conceptual design of thermodynamic cycles the important questions concern the operating conditions and estimates of efficiency and cooling/heating/power produced by the cycle.

CyclePad works in two phases, build mode and analyze mode. In the first phase (build), you use a graphical editor to place components and connect them with stuffs. A thermodynamic cycle consists of a collection of components connected together in some appropriate fashion. The components CyclePad knows about include compressors, turbines, heaters, coolers, pumps, mixers, splitters, throttles, and heat exchangers. CyclePad describes connections in terms of the properties of the material at the connection, that is, the properties of the stuff that is flowing between the components.

Simple Rankine Cycle

In the above diagram, for example, you will see that there are four components: a heater, a turbine, a cooler, and a pump. These components are connected via four stuffs, S1, S2, S3, and S4. The major source of information about the cycle is the set of parameters associated with each stuff and each component. CyclePad knows what parameters are associated with each component and with each stuff. It knows that the set of what parameters are relevant can vary; when a stuff is saturated, for example, its dryness (quality) becomes relevant, and a turbine which is not approximated as isentropic requires some specification of its presumed efficiency. Part of your job as a designer is selecting numerical values and modeling assumptions to see if a particular design can satisfy your performance criteria (e.g., desired work output, efficiency, etc.)

Source/References : Northwestern University- CyclePad

DOWNLOAD :
CYCLEPAD.RAR



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Software : Computer-Aided Thermodynamic Tables 2

Computer-Aided Thermodynamic Tables 2 (CATT2) provides you with a means to access various thermodynamic tables normally found in text or reference books. There is no need to interpolate values from a table. You simply enter a property value you want to evaluate, and let the computer do the work.
The good things here is the software is a Windows application so it is more user friendly. Another advantage is the better visual steam or gas table that can show the point of the state.

The CATT2 screen is divided into an upper and lower section. The upper section displays the values last evaluated and, in some cases, a graphical representation of those values. The lower section contains a spreadsheet-like log of all previous values evaluated for a particular substance. The sections are separated by a draggable bar, which allows you to view more or less of each section.

You can evaluate all of the tables using one of four predefined sets of units. You can select units prior to performing any calculations, using Change Units from the menu or clicking the Units button.
The tables are grouped as following :
- Water
- Refrigerants
- Cryogenics
- Air
- Ideal Gases
- Compressibility
- Psychrometrics

You can access each group by clicking on the corresponding tabs, at the bottom of the display, or by selecting the group from the Tables menu.

System Requirements :
Windows (98/2000/XP). (I do not have any experiences using Vista...)

DOWNLOAD : CATT.RAR



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Software : FREECORP V1.0 - a simple corrosion model

[1]...FREECORP V1.0 is a simple corrosion model, strongly rooted in theory, which has been developed exclusively based on public knowledge. Currently, this model is capable of predicting uniform corrosion of carbon steel at a single point in an environment containing carbon dioxide, acetic acid, oxygen, and/or hydrogen sulfide. Iron carbonate film formation, a key factor in carbon dioxide corrosion, is simulated using an empirical correlation to improve the accuracy of corrosion rate prediction. Contributions to corrosion of various corrosion species can be calculated, which enables the exploration of dominant corrosion species in the corrosion process. Furthermore, polarization curves for each individual electrochemical reaction, total cathodic and anodic reactions and polarization sweeps can be optionally displayed. In a case of hydrogen sulfide corrosion, film formation is calculated and concentration profile of H2S across mass transfer layers on steel surface is displayed.

FREECORP is a user friendly Excel add-in which allows rapid corrosion prediction calculation and display of the dominant corrosion mechanism. The program determines the dominant mechanism and displays its graph.

For the case of CO2 dominated corrosion the interface shows a polarization plot:

For the case of H2S dominated corrosion the interface shows a polarization plot:

The user also has the option of performing a what-if analysis by adding or removing individual corrosion species from the calculated model. The result of the corrosion calculations and the corresponding plot can be saved into an Excel file.

Reference :
[1] : LINK

Download Link Source : FREECORP V1.0

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Software : Combustion Analysis

This software is using for combustion analysis for many kind of substances and it can use SI or English units. The temperature can be set up for absolute or non-absolute units. It can analyze about 17 substances :

- Methane
- Ethylene
- Propylene
- Porpane
- 1-Butane
- N-Butane
- N-Pentane
- Benzene
- 1-Hexane
- N-Hexane
- Toluene
- 1-Heptane
- N-Heptane
- 1,4-Dimethylbenzene
- 1-Octane
- Normal Octane

Combustion system can be set up for open or close system and also control volume or constant volume.

Download : COMBUSTION ANALYSIS

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Fundamentals Handbook : Fluid Flow, Fluid Mechanics

This module describes the relationship between the different types of energy in a fluid stream through the use of Bernoulli's equation. The module also discusses the causes of head loss in fluid systems and what factors affect head loss.

TOC :
Chapter 1 : CONTINUITY EQUATION
Introduction, Properties of Fluids, Buoyancy, Compressibility, Relationship Between Depth and Pressure, Pascal’s Law, Control Volume, Volumetric Flow Rate, Mass Flow Rate, Conservation of Mass, Steady-State Flow, Continuity Equation

Chapter 2 : LAMINAR AND TURBULENT FLOW
Flow Regimes, Laminar Flow, Turbulent Flow, Flow Velocity Profiles, Average (Bulk) Velocity, Viscosity, Ideal Fluid, Reynolds Number

Chapter 3 : BERNOULLI’S EQUATION
General Energy Equation,Simplified Bernoulli Equation, Head,Energy Conversions in Fluid Systems, Restrictions on the Simplified Bernoulli Equation, Extended Bernoulli, Application of Bernoulli’s Equation to a Venturi

Chapter 4 : HEAD LOSS
Head Loss, Friction Factor, Darcy’s Equation,Minor Losses, Equivalent Piping Length

Chapter 5 : NATURAL CIRCULATION
Forced and Natural Circulation, Thermal Driving Head, Conditions Required for Natural Circulation, Example of Natural Circulation Cooling, Flow Rate and Temperature Difference

Chapter 6 : TWO-PHASE FLUID FLOW
Two-Phase Fluid Flow, Flow Instability, Pipe Whip, Water Hammer, Pressure spike, Steam Hammer, Operational Considerations

Chapter 7 : CENTRIFUGAL PUMPS
Energy Conversion in a Centrifugal Pump, Operating Characteristics of a Centrifugal Pump, Cavitation, Net Positive Suction Head, Pump Laws, System Characteristic Curve,
System Operating Point, System Use of Multiple Centrifugal Pumps, Centrifugal Pumps in Parallel, Centrifugal Pumps in Series

Source : D O E

DOWNLOAD :
FLUID FLOW




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Fundamentals Handbook : Heat Transfer

This module describes conduction, convection, and radiation heat transfer. The module also explains how specific parameters can affect the rate of heat transfer. And at the chapter 6-8 explain about Heat Transfer of Nuclear means.

Content :
Chapter 1 :HEAT TRANSFER TERMINOLOGY
Heat and Temperature, Heat and Work, Modes of Transferring Heat, Heat Flux, Thermal Conductivity, Log Mean Temperature Difference, Convective Heat Transfer Coefficient, Overall Heat Transfer Coefficient, Bulk Temperature

Chapter 2 : CONDUCTION HEAT TRANSFER
Conduction, Conduction-Rectangular Coordinates, Equivalent Resistance Method, Electrical Analogy, Conduction-Cylindrical Coordinates

Chapter 3 : CONVECTION HEAT TRANSFER
Convection, Overall Heat Transfer Coefficient, Convection Heat Transfer

Chapter 4 : RADIANT HEAT TRANSFER
Thermal Radiation, Black Body Radiation, Emissivity, Radiation Configuration Factor

Chapter 5 : HEAT EXCHANGERS
Heat Exchangers, Parallel and Counter-Flow Designs, Non-Regenerative Heat Exchanger, Regenerative Heat Exchanger, Cooling Towers, Log Mean Temperature Difference, Application to Heat Exchangers, Overall Heat Transfer Coefficient

Chapter 6 : BOILING HEAT TRANSFER
Boiling, Nucleate Boiling, Bulk Boiling, Film Boiling, Departure from Nucleate Boiling and Critical Heat Flux,

Chapter 7 : HEAT GENERATION
Heat Generation, Flux Profiles, Thermal Limits, Average Linear Power Density, Maximum Local Linear Power Density, Temperature Profiles, Volumetric Thermal Source Strength, Fuel Changes During Reactor Operation

Chapter 8 : DECAY HEAT
Reactor Decay Heat Production, Calculation of Decay heat, Decay Heat Limits, Decay Heat Removal

Source : D O E

Download :
D O E





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Software : Steam Table in SI or English Unit

This is a steam table program. This small program can help you to solve thermodynamics steam problems. You can select for SI or English system of units. You can choose 7 cases variation of known properties. Those are :

- P (saturation) and Quality
- P and T
- P and v

- P and s
- P and h
- T (saturation) and quality
- T and v

This program can identified the state of steam (liquid vapor. superheated etc.)



Platform : MSDOS / WINDOWS
Developed by : M. Boles
Requirements : All WINDOWS VERSION (support MSDOS Command)

Source : DOWNLOAD

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Software : Ideal Gas Tables in SI or English Unit

This light software is very useful for solving Ideal Gas Properties problems. We may use Ideal Gas Table because sometimes known properties given are not complete. It is very helpful to find another properties Ideal.gas table can help just only using couple properties from specified ideal gas. This software assumes that the specific heats are functions of temperatures.

You can select for SI or English system of units. Temperature can be selected for absolute (Kelvin or Rankine) or non-absolute units (Celcius or Fahrenheit). The specific properties may be expressed per unit mass or mole. And then many of the thermodynamics properties of the gases may determined. Those gases are :

- Air
- Argon
- Carbon monoxide CO
- Carbon dioxide CO2
- Hydrogen atom H
- Hydrogen H2
- Hydroxyl OH
- Nitrogen atom N
- Nitrobeg N2
- Nitroen Oxide NO
- Nitrogen dioxide NO2
- Oxygen atom O
- Oxygen O2
- Water vapor H2O

This program is bundled with "Thermodynamics : An Engineering Approach" book by Y. Cengels and M. Boles. This book is intended for use as a textbook by undergraduate engineering students in their sophomore or junior year, and as a reference book for practicing engineers.

Platform : MSDOS / WINDOWS
Developed by : M. Boles
Requirements : All WINDOWS VERSION (support MSDOS Command)

Source : DOWNLOAD

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Fundamentals Handbook : Thermodynamics

This module explains the properties of fluids and how those properties are affected by various processes. The module also explains how energy balances can be performed on facility systems or components and how efficiency can be calculated.This is module 1 of 3. Module 2 is about Heat Transfer and module 3 is about Fluid Flow.

Table of Content :
Chapter 1 : THERMODYNAMIC PROPERTIES
Mass and Weight, Specific Volume, Density, Specific Gravity, Humidity, Intensive and Extensive Properties

Chapter 2 : TEMPERATURE AND PRESSURE MEASUREMENTS
Temperature, Temperature Scales, Pressure, Pressure Scales

Chapter 3 : ENERGY, WORK, AND HEAT
Energy, Potential Energy, Kinetic Energy, Specific Internal Energy, Specific P-V Energy, Specific Enthalpy, Work, Heat,Entropy, Energy and Power Equivalences

Chapter 4: THERMODYNAMIC SYSTEMS AND PROCESSES
Thermodynamic Systems and Surroundings, Types of Thermodynamic Systems, Thermodynamic Equilibrium, Control Volume, Steady State, Thermodynamic Process, Cyclic Process, Reversible Process, Irreversible Process, Adiabatic Process, Isentropic Process, Polytropic Process, Throttling Process

Chapter 5 : CHANGE OF PHASE
Classification of Properties, Saturation, Saturated and Subcooled Liquids, Quality, Moisture Content, Saturated and Superheated Vapors, Constant Pressure Heat Addition, Critical Point, Fusion, Sublimation, Triple Point, Condensation

Chapter 6 : PROPERTY DIAGRAMS AND STEAM TABLES
Property Diagrams, Pressure-Temperature (P-T) Diagram, Pressure-Specific Volume (P-v) Diagram, Pressure-Enthalpy (P-h) Diagram, Enthalpy-Temperature (h-T) Diagram, Temperature-Entropy (T-s) Diagram, Enthalpy-Entropy (h-s) or Mollier Diagram, Steam Tables

Chapter 7 : FIRST LAW OF THERMODYNAMICS
First Law of Thermodynamics

Chapter 8 : SECOND LAW OF THERMODYNAMICS
Second Law of Thermodynamics, Entropy, Carnot’s Principle, Carnot Cycle,Diagrams of Ideal and Real Processes, Power Plant Components, Heat Rejection, Typical Steam Cycle, Causes of Inefficiency


Chapter 9 : COMPRESSION PROCESSES
Boyle’s and Charles’ Laws, Ideal Gas Law, Fluid, Compressibility of Fluids,Constant Pressure Process,Constant Volume Process, Effects of Pressure Changes on Fluid Properties, Effects of Temperature Changes on Fluid Properties

Source : D O E

DOWNLOAD :
Thermodynamics



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Analysis of Cavitation Phenomena in Water and its Application to Prediction of Cavitation Erosion in Hydraulic Machinery

The cavitating flow behaviour is very sensitive to nuclei content, which is undoubtedly dependent on the physical properties of the liquid. For water, it is believed that heterogenous nucleation initiators prevail over homogeneous nucleation and this is understood to be the reason why the classical nucleation theories are regarded as unreliable for the treatment of cavitation.
As a result, the problem of nuclei content is typically treated either empirically or experimentally. In this paper we show how the empirical approach can be used to obtain a useful picture of the cavitation flow aggressiveness (erosion potential) using numerical modelling of the turbulent cavitating flow. In addition, we present the latest advances in the understanding of the bubble nucleation process under cavitating conditions based on the modified binary nucleation theory.

In this article we also shortly describe the experimental research of the cavitating flow aimed at the validation of the erosion potential model, development of the nuclei-content measurement and the validation of the bubble nucleation model. As far as the practical application of our work is concerned, the paper concentrates on an evaluation of the cavitation erosion potential in the hydraulic machinery, mainly water pumps and turbines.

Introduction
In general, there are three major reasons for numerical modelling of cavitation in industrial applications. The first reason is to predict changes in the flow field caused by the cavitation phenomena, which result mainly in a degradation of machine performance. The second reason is to determine cavitation instabilities, which can generate unwanted noise and vibrations. The third reason is to assess the potential of material erosion due to cavitation and to determine the areas on the blade surface (for example in pumps), which are most endangered with erosion. In all the above cases cavitation depends on many factors, which can be divided into two categories: hydrodynamic factors (such as flow parameters or turbulence level)and factors associated with the liquid properties (such as surface tension, bubble content and liquid composition).

Nevertheless cavitation is mainly treated as a solely hydrodynamic problem and the dependence on the physical properties of the liquid is typically neglected. Prediction of cavitation phenomena in hydraulic devices is usually based on the assumption that a given spectrum of cavitation
nuclei flow through the regions with rapidly changing static pressure, which results in a very complicated dynamic behaviour of the cavitation bubbles. From the point of view of an engineer one of the important challenges of the cavitation research is the determination of the number and size of the cavitation nuclei. These quantities naturally depend on the liquid properties; however, they are usually predicted empirically or by rather expensive and complicated measurements on the case-to-case basis. The consequences are most obvious in the case of water when the experimental measurements of the cavitation events under exactly the same hydrodynamic conditions can give very different results.


The main problem in the theoretical estimation of the cavitation nuclei spectrum in water is that the classical nucleation theory predicts only one (critical) bubble size and that the bubble nucleation rate is much higher than the experimentally observed rate. This is true mainly in the case of pure water. The situation is simplified when we consider that the water running trough the hydraulic machinery parts contains a known number of air-filled or vapour-filled microbubbles of known size distribution.

Summary and Conclusion
In this paper we have shortly described the numerical modelling as well as the experimental research of cavitation in hydraulic machines. The main interest was focused on the flow aggressiveness associated with cavitation. The presented numerical model predicts regions highly endangered by the bubble collapses as well as the energy of these collapses denoted as “erosion potential”. The first stage of experimental research in the cavitation tunnel was also presented.

This stage is aimed at validation of the erosion potential model, visualisation of the cavitation bubbles, development of the nuclei content measurement and the validation of the bubble nucleation model. Though the nuclei content in the numerical model was still determined empirically, the agreement of the theoretical results and the observations is encouraging. The measurements of the cavitation nuclei in water by light scattering and the acoustic spectrometry are being completed to provide accurate nuclei distribution. Finally, we have shown that the Classical Nucleation Theory can be improved to reliably predict the process of bubble nucleation under cavitation conditions. As far as the practical application of our work is concerned, the paper demonstrates the analysis of the cavitation erosion in the impeller of the mixedflow water pump.

by : Milan Sedlář, Patrik Zima, Tomáš Němec and František Maršík

Source : LINK

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