Service Encounter Journal and Analysis Personal Statement

Service Encounter Journal and Analysis - Personal Statement Example I stopped at this convenience store to buy fuel and get a newspaper. I was involved with an employee at the check-out register. My overall satisfaction is rated at 2, because the cashier was upset when I misspoke about how much money I had, so she had to cancel the transaction on her register. Although I apologized for causing her the extra work, she did not look appeased, and made a remark to her coworker about it as I left. I am definitely not going to purchase from them again (score of 1). I visited this store to pick up a few groceries and had two interactions with employees: one directed me to the right part of the store to find cake mix, and the cashier rang up my purchase. My overall satisfaction is rated at 7, because the employee who directed me completely stopped what he was doing to talk, made eye contact, and appeared pleased to help. Also, the cashier let me use the special discount card they keep for customers who forgot theirs. They were professional and efficient, so I will definitely return (score of 7). My object in visiting the bank was to purchase two savings bonds. The bank uses tellers to complete such transactions. My overall satisfaction is rated at 2, because the teller clearly did not want to conduct this lengthy business. I wrote down important information for her, but she copied it incorrectly into the computer, so it had to be changed. I only had time to buy one bond, and then had to leave because I was going to be late for another appointment. Perhaps I could have come in the middle of the morning when the bank was not so busy. The teller could have been more efficient and not shown her displeasure. Still, my accounts are there, so I rate my likelihood to return at 7. Journal Entry: 5 Week: 5 Firm: Bill's Barber Shop Type of Service: Personal care My hair was getting long, so I visited the shop for a trim. Employee involvement came from the person who greeted me and the barber who cut my hair. My overall satisfaction is rated at 4. I received a good haircut at a good price, but it took a very long time. The barber should have kept working while he talked to me, but instead, liked to stop and make eye contact for every sentence! I could have asked the barber to work faster, or he could have sensed that I felt it was taking too long. My likelihood of returning is rated at 1. There are other shops in town. Journal Entry: 6 Week: 6 Firm: Nationwide Insurance Co. Type of Service: Auto and home insurance It was time to make my car insurance payment, and I dealt with a representative who accepted my check and gave me a receipt. She also set me up for electronic fund transfers. My overall satisfaction is rated at 6, because she was quick, efficient, and courteous. There was nothing she or I could have done to make the transaction better. My likelihood of returning is rated 7. They have earned my business and loyalty. Journal Entry: 7 Week: 7 Firm: US Postal Service Type of Service: Package delivery I had to ship a large package, and the

Web Portal. Environmental Research Data Management Essay

Web Portal. Environmental Research Data Management - Essay Example Ecology may generally be defined as the relationship between living organisms, including plants and animals, and their environment (Levitt, 2008). It will be noted that the living organic component of the environment has so much dominance on the outcome and preservation of the environment. Much of the issue of environmental outcome and preservation also depends largely on how these living organisms relate to each other and influence the living of each other. In today’s era of environmental advocacy for the conservation and preservation of the environment therefore, it is proposed that the use of ecological web portals could be used as very effective avenues and media for the promotion of environmental awareness on how human behaviour in the ecosystem can influence the perpetual conservation and eventual preservation of the environment. The idea behind the use of ecological web portals to promote environmental protection is to ensure that there is a centralized destination and system, from which data and information regarding environmental interactions between various living organisms, and more specifically the effect of human behaviour on the environment can be sampled from. To effectively achieve the goal of the proposal, it is expected that a number of research questions will be answered. Through the use of research data collection in answering these questions, it is expected that the aim of the proposal will be achieved in the long while. The research questions are given as follows: 1. What are the specific human behaviours that impact on the environment negatively? 2. How can the use of a centralized web portal be used to solve these problems? 3. How can the use of web portals be promoted to reach a wider audience to play the role for which it is implemented? 4. What challenges are likely to be faced in the use of ecological web portal to promote environmental protection? In relation to the first research question, it will be noted that the human spe cies is a very powerful component of the ecosystem, which controls majority of the interactive activities that take place within the environment. This is said because the human beings have the power to raise other organisms and species within the ecosystem such as animals and plants and directly influence the way that these species relate to the environment. Due to this power possessed by humans, there are number behaviours that they put up that have been identified to affect the ecosystem negatively. In an attempt to answer the first research question therefore, the researcher shall undertake a comprehensive and systematic literature search to come to terms with examples of human behaviours and practices that affect the environment negatively. It is proposed that when most of these ecological practices and behaviours are known, it will pave the way for much information to be given on these behaviours on the web portals to the designed. Another relevance of this research question is that when the specific behaviours that affect the ecology are not known, the portal will only be championing a course that does not affect its users in any way. On the use of a centralised web portal to solve problems related environmental protection, it can said that this is a more modern form of information transmission that promises to have a larger reach and coverage than most available avenue (Popovic et al, 2005). This is because web portals are seen as components of the new media and for that matter, social media that have currently taken over the use of the internet. Because of the scope of users of web portals, the coverage of the advocacy that will take place will be impacting. For instance schools of higher education including universities, could become major targets for

Question and Quote Essay Example | Topics and Well Written Essays - 500 words

Question and Quote - Essay Example This action is to strengthen the financial structure of the country through the regulation of the individual institutions and the promotion of the interdependence of the financial firms and the participants of the financial system (Morgan Lewis Website, 2009, p.1; US Department of Treasury, 2009) The need for the improvement of the regulation of financial firms had been realized during the latest financial crisis due to the credit boom and housing bubble. This triggered the need for reformation of the financial system (Walker, 2009, p.1). The action of the US government is an immediate response to the need of the nation. There are comments and criticisms on the limitations of the Financial Regulatory Reform. On a personal point of view, the US government made an immediate effort to act upon the financial crisis, thus, it is commendable. This hindered the worsening of the situation. At such a short period of time, alertness had been a crucial strategy. II.

Story of an hour Essay Example for Free

Story of an hour Essay ?Prompt: Read â€Å"The Story of an Hour† carefully. Examine the protagonist’s attitude about the death of her husband. How is this attitude revealed and how does it contribute to the meaning of the story? Authors reveal characters attitudes through different literary devices. In â€Å"The Story of an Hour†, the author Kate Chopin, uses irony to reveal Mrs. Mallard’s attitude toward her new husband’s death. Chopin first describes in the story how a typical woman might respond to her husband’s death. â€Å"She did not hear the story as many women have heard the same, with a paralyzed inability to accept its significance. † Most women would have been in shock and not want to accept the fact that their husband had indeed passed away. However, Mrs. Mallard had a rather ironic reaction. She wept suddenly and wanted to be alone. This revealed she was not like most women and had a rather peculiar view about her husband’s death. As the reader continues, they discover more irony into Mrs. Mallard’s attitude. After she has retreated to a room to isolate herself from the others, she sits in a chair facing a window and whispers to herself, â€Å"Free, free, free! † No widow would whisper that only minutes after their husbands death, if ever at all. Though she knows her husband had loved her, and she had loved him, she had felt trapped inside their marriage. Now recognizing she has regained her freedom, her sense of entrapment diminishes. The irony continues as the reader learns Mrs. Mallard’s husband had not actually died. Not only is the reader in shock, but so is Mrs. Mallard. So shocked in fact, that she dies at her husband’s arrival. â€Å"When the doctor came they said she had died of a heart disease – of joy that kills. † Mrs. Mallard had actually died because for one hour she actually got to live with true freedom. Most women would be overwhelmed with joy that their husband was alive, where as Mrs. Mallard has more of an ironic reaction. She had realized at the sight of her husband that her glimpse of freedom and joy was over, and she could not go back to living under her husband’s will. Her final attitude towards the death of Mr. Mallard is revealed, Mrs. Mallard was happier as a widow. Kate Chopin uses irony as a literary device to reveal her character, Mrs. Mallard’s attitude towards her husband’s death.

Performance Of Wells Turbine Engineering Essay

Performance Of Wells Turbine Engineering Essay ABSTRACT A Wells turbine has inherent disadvantages in comparison with conventional turbines: relative low efficiency and poor starting characteristics. In this case, the performance of wells turbine is studied on computational analysis by changing aerofoils and providing different angle of incidence for the improvement of the turbines performance. Study is based on analysing the flow of air on turbine using computational analysis at steady condition. 1 INTRODUCTION: The Ozone depletion and global warming have altered the international community and urged the need for more focus on alternative green sources of energy. Ocean wave energy is one of the renewable forms of energy which can be utilized in response to the disturbing prospect of an exhaustible source of energy. Several wave energy devices being studied under many wave energy programs make use of the principle of the oscillating water column (OWC).Potentially; the most successful device used in harnessing on wave energy has been the OWC wave energy converter. The OWC chamber, either floating or bottom standing, with the immersed end opened to the action of the sea. A reciprocating airflow is created by the action of the free surface of the water within the chamber. The conversion of this airflow into mechanical energy may be achieved by a number of devices like:- A. TAPCHAN: The TAPCHAN comprises a gradually narrowing channel with wall heights typically 3 to 5 m above mean water level. The waves enter the wide end of the channel and, as they propagate down the narrowing channel, the wave height is amplified until the wave crests spill over the walls to a reservoir which provides a stable water supply to a conventional low head turbine. The requirements of low tidal range and suitable shoreline limit the world-wide installation of this device. Fig (a) TAPERED CHANNEL[1] (TAPCHAN)http://re.emsd.gov.hk/english/other/marine/images/marine_tech_010_2.gif B. PENDULOR: The PENDULOR device consists of a rectangular box, which is open to the sea at one end. A pendulum flap is hinged over this opening, so that the action of the waves causes it to swing back and forth. This motion is then used to power a hydraulic pump and generator.http://t2.gstatic.com/images?q=tbn:ANd9GcQ7yge9ouptnhszDgsXGA_gCvAXKqbo78BeXZHFFtPB89433p0p Fig (b) PEDULOR [2] C. WELLS TURBINE: The Wells turbine is one of the most suitable air turbines for energy conversion from oscillating air flow. . A schematic view of the OWC device with a Wells turbine is shown in Fig. c. The Wells turbine is an axial flow air turbine. It consists of several symmetrical aerofoil blades set around a hub. As waves Impinge on the device, they cause the water column to rise and fall in the air chamber, which alternately compresses and depressurized the trapped air. This air is allowed to flow to and from the atmosphere through a turbine which drives an electric generator.http://www.aussiestockforums.com/forums/attachment.php?attachmentid=9213stc=1d=1180172232 Fig (c) WELLS TURBINE[3] Fig. 1.1: Schematic of the Three Major shoreline Devices The Wells turbine is a self-rectifying air turbine which is expected to be widely used in wave energy devices with the OWC (Raghunathan, 1995) .It can extract power at low airflow rate, when other turbines would be inefficient. The Wells turbines for wave power conversion have less efficiency. To increase the efficiency is the major quest all over the world, the flow of air through the wells turbine impeller is carried out in this project by using different size impeller and introducing biplane i.e. two rows of symmetrical aerofoil blades. 1.1 WAVE RESOURCEShttp://www.oceanenergy.ie/images/world-map.jpg Fig. 1.2: Global Distribution of Deep Water Wave power levels in kW/m crest length[4] Despite the climate change phenomena, the world resource for wave remains very much as shown in fig. 1.2 by Dr Tom Thorpe [5]. The highest energy waves are concentrated off the western coasts in the 40o-60o latitude range north and south. The power in the wave fronts varies in these areas between 30 and 70kW/m with peaks to 100kW/m in the Atlantic SW of Ireland, the Southern Ocean and off Cape Horn. The capability to supply electricity from this resource is such that, if harnessed appropriately, 10% of the current level of world supply could be provided [4] PERIOD AMPLITUDE POWER DENSITY VELOCITY (m/s) WAVELENGTH (sec) (m) (kW/m) (m) Storm 14 14 1700 23 320 Average 9 3.5 60 15 150 Calm 5.5 0.5 1 9 50 Fig: 1.3 Tthe nautral and technical wave energy resource for the north and west side of the UK[6] The techinical resource is dependent on the nautral conditions like the shape of the rock and location i.e beaches and gullies. The wave energy at calm sea is considered in this project. 1.2 WELLS TURBINE The monoplane Wells turbine i.e. the basic Wells turbine consists of several symmetrical aerofoil blades (NACA four digit series) set around a hub at 90 degrees with respect to the airflow. Since its an invention by Prof. A.A. Wells in 1976, most researchers have focused on improving its efficiency and its range of efficient operation. In fact, compared to other conventional air turbines (e.g. Francis turbine) the Wells turbine has a lower efficiency and a narrow operational region. Nevertheless, it can extract power at low airflow rate, when other turbines would be inefficient. Fig. 1.4: Schematic of the Monoplane Wells Turbine[7] A schematic diagram of a Wells turbine is shown in Fig. 1.4. At first sight the arrangement might seem to be unlikely means of energy conversion. However, once the blades have attained design speed the turbine is capable of producing a time-averaged positive power output from the cyclically reversing airflow with a fairly high efficiency. Wells turbine has low efficiency and poor starting characteristics. The Biplane Wells turbine: Muhammad Mamun in the Study on the Hysteretic Characteristics of the Wells Turbine in a Deep Stall Condition says the pressure drop across a mono-plane Wells turbine above is proportional to the square of the tip speed which has to be limited if transonic effects are to avoided. For wave energy devices which produce significantly larger pressure drops than the limit for a single plane turbine a biplane turbine can be used Fig. 1.5: Schematic of the Biplane Wells [7] It has certain advantages over the conventional monoplane Wells turbine as follows: I. It can operate under high loading. II. It can absorb higher wave power than the monoplane turbine if the diameter and rotational speed of the turbine are kept constant. III. The design speed is lower than that of the monoplane for the same loading. IV. It avoids the use of guide vanes and therefore the turbine would require less maintenance and repairs. [7] 1.3 PRINCIPLE OF OPERATION The principle of operation of Wells turbine is based on the classical aerofoil theory. According to the classical aerofoil theory, an aerofoil which is set at an angle of incidence ÃŽÂ ± in a fluid flow generates a lift force L normal to the free stream. The aerofoil also experiences a drag force D in the direction of the free stream (relative velocity). These lift and drag forces can be resolved into tangential (in the plane of rotation) and axial (normal to the plane of rotation) components FT and FA respectively. Fig. 1.6 Notation for determining lift, drag, and axial and tangential forces on An aerofoil[7] Resulting expression for axial and tangential forces FA = LcosÃŽÂ ± + DsinÃŽÂ ± FT = LsinÃŽÂ ± DcosÃŽÂ ± The axial force is absorbed but the turbine while the tangential force causes the turbine to rotate. For a symmetrical airfoil the direction of tangential force is the same for both positive and negative values of ÃŽÂ ±. Therefore, the direction of rotation of the rotor is independent of airflow direction. 2 AIMS AND OBJECTIVES OF THE PROJECT Simulation of air flow through wells turbine impeller by means of numerical method using a CFD (Computational fluid dynamics) called FLUENT and check the flow process of different parameters and the factors affecting the differences. Since wells turbine is a low efficiency turbine to increase the efficiency of Wells turbine is the other aim. Path followed to meet the requirements is first calculation of efficiency theoretically. Simulating a modified design by using different angle of incidence and making biplane i.e. two rows. Comparing the results of different model and selecting the suitable design. 3 LITERATURE REVIEW: 3.1 Types of CFD PROCESS USED: Commercial CFD code: FLUENT, Star-CD, FLOW-3D, CFX/AEA, etc. Research CFD code: Self-developed Public domain software (PHI3D, HYDRO, and WinpipeD, etc.) Other CFD software includes the Grid generation software (e.g. Gridgen, Gambit) and flow visualization software (e.g. Tecplot, FieldView) Commercial CFD code FLUENT is used in this project. 3.2 General working on CFD Table3.1: CFD working layout The Processes shown in the table 3.1 is divided into pre- process and post- process viz. GAMBIET AND FLUENT General sequence of GAMBIT operations Initial setup Solver selection, Mesh size, Defaults, etc. Geometry creation (ACIS, IGES or Mesh import) Create full geometry Decompose into mesh-able sections Meshing Local meshing: Edge and Boundary layers Global meshing: Face and/or Volume Mesh examination Zone assignment Continuum and Boundary attachment Mesh export General sequence of FLUENT operations Selection of appropriate models. Turbulence, combustion, multiphase, etc. Define material properties Fluid Solid Mixture Prescribe operating conditions Prescribe boundary conditions at all boundaru zones Provide and initial solution Set up solver controls Set up convergence monitors 3.3 Grid generation: Grid generation is one of the key elements in Computational Fluid Dynamics (CFC). It has now become a fairly common tool for use in the numerical solution of partial differential equations on arbitrarily shaped regions. The numerical solution of partial differential equations requires some discretization of the field into a collection of points (nodes) or elemental volumes (cells). The differential equations are approximated by a set of algebraic equations on this collection, and this system of algebraic equations is then solved to produce a set of discrete values which approximates the solution of the partial differential system over the field. The practice of discretizing the physical domain into a finite number of elements is called as grid generation. 3.4 Grid topologies Generally, the governing equations may be transformed into finite element, finite difference, or finite volume equations. The cell types supported by FLUENT are followed as: triangular and quadrilateral cells in 2D are accepted, and in 3D, tetrahedral, hexahedral, wedge, and pyramid cells can be used FIG3.2: Different types of grids Structured versus Unstructured Grids The section presents a brief description of grid generation. The grid generation techniques available at present fall into two categories, namely: a) structured grid generation and b) unstructured grid generation. The structured grid generation techniques are based on the transformation of the complex physical domain into a simple computational domain, which is often chosen to be rectangular in shape (quadrilateral and hexahedron). The unstructured grid generations have been used with FEM (finite element method) procedure only, whereas structured grids have general applicability.[7] . 3.5 Types of structured grid In FLUENT, both single-block and multi-block structured meshes are acceptable, as well as hybrid meshes containing quadrilateral and triangular or hexahedral, tetrahedral, pyramid, and wedge cells Multiple Block Sometimes, it is possible to combine several structured computational meshes together to fit the physical domain. Multi- locking has the advantage of the speed of a structured solver, without as many mapping constraints apparent in single block meshes. Single Block In this technique, one computational grid is mapped to fit the whole physical domain. For even moderately complex shapes, it may be practically impossible to define a transformation which will map the outer surface of the computational domain to the required physical shape, while ensuring that the resulting grid has desirable attributes of smoothness.[7] 3.6 Mesh quality The quality of mesh plays a significant role in the accuracy and stability of the numerical simulations. The attributes associated with mesh quality are density of node, cell shape, smoothness and flow-field dependency. In many cases, poor resolution in critical regions can dramatically alter the flow characteristics. 3.7 The Capabilities of FLUENT This section provides a brief introduction to FLUENT and an explanation of its capabilities [10].FLUENT used in this project is a commercial code and a state-of-the-art computer program for modelling single and multiphase flows, heat and mass transfer, chemical reaction phenomena, and etc. in complex geometries. This code includes following components; FLUENT, the flow solver; GAMBIT, the pre-processor for geometry modelling and mesh generation; pre-PD, and etc. FLUENT solver utilizes a finite-volume, pressure-based, multiphase space marching method (SIMPLE algorithm), for solving the governing integral equations for conservation of mass and momentum, and for energy and other scalars such as turbulence and chemical species. It has the following modelling capabilities: à ¢Ã¢â€š ¬Ã‚ ¢ Flows in 2D or 3D geometries using triangular/tetrahedral, quadrilateral/hexahedral, or mixed (hybrid) grids that include prisms (wedges) or pyramids à ¢Ã¢â€š ¬Ã‚ ¢ In compressible or compressible flows à ¢Ã¢â€š ¬Ã‚ ¢ Steady-state or transient analysis à ¢Ã¢â€š ¬Ã‚ ¢ Laminar and turbulent flows à ¢Ã¢â€š ¬Ã‚ ¢ Newtonian or non-Newtonian flow à ¢Ã¢â€š ¬Ã‚ ¢ Convective heat transfer, including natural or forced convection à ¢Ã¢â€š ¬Ã‚ ¢ Coupled conduction/convective heat transfer à ¢Ã¢â€š ¬Ã‚ ¢ Radiation heat transfer à ¢Ã¢â€š ¬Ã‚ ¢ Inertial (stationary) or non-inertial (rotating) reference frame models à ¢Ã¢â€š ¬Ã‚ ¢ Multiple moving reference frames, including sliding mesh interfaces and mixing planes for rotor/stator interaction modelling à ¢Ã¢â€š ¬Ã‚ ¢ Chemical species mixing and reaction, including combustion sub models and surface deposition reaction models à ¢Ã¢â€š ¬Ã‚ ¢ Arbitrary volumetric sources of heat, mass, momentum, turbulence, and chemical species à ¢Ã¢â€š ¬Ã‚ ¢ Flow through porous media à ¢Ã¢â€š ¬Ã‚ ¢ One-dimensional fan/heat-exchanger performance models à ¢Ã¢â€š ¬Ã‚ ¢ Two-phase flows, including cavitations à ¢Ã¢â€š ¬Ã‚ ¢ Free-surface flows with complex surface shapes FLUENT can provides a number of boundary conditions, including: à ¢Ã¢â€š ¬Ã‚ ¢ Velocity or Pressure Driven Inlets/Outlets à ¢Ã¢â€š ¬Ã‚ ¢ Stationary or Moving Walls, with or without Friction à ¢Ã¢â€š ¬Ã‚ ¢ Periodic Boundary Conditions à ¢Ã¢â€š ¬Ã‚ ¢ Symmetry Boundary Conditions à ¢Ã¢â€š ¬Ã‚ ¢ Pressure Far-filed Boundary Conditions à ¢Ã¢â€š ¬Ã‚ ¢ Outflow Boundary Conditions à ¢Ã¢â€š ¬Ã‚ ¢ Inlet/Outlet Vent Boundary Conditions à ¢Ã¢â€š ¬Ã‚ ¢ Intake/Exhaust Fan Boundary Conditions As the Well turbine has a complex geometry for modelling, a large number of modelling capabilities are required of the CFD code for the turbine. FLUENT can incorporates all of these capabilities, and is most suitable for modelling the Wells turbine.[10] 4 ANALYSIS OF TASK 4.1 Theoretical calculation: The dimension used in this project is of prototype obtained from others experimental work, the model is designed and simulated by using the two different models shown in the table below. a [8] b[9] Table 4.1 Dimension of wells turbine The theoretical calculation of efficiency is done using the above two different dimension, the method used to calculate the efficiency is shown below. CALCULATION FOR EFFICIENCY: Similarly, CALCULATION AT 4 DEGREE ANGLE OF ATTACK: At ÃŽÂ ±= 4 degree The table below shows a calculated efficiency at different angle of attack calculated using the format shown above. ÃŽÂ ±(degree) ÃŽÂ ±(radians) W(relative velocity) à Ã¢â‚¬ °(rads/sec) Re Cl Cd ÃŽÂ · 4.00 0.07 143.36 42.45 1221641.45 0.40 0.01 21.86 5.00 0.09 114.74 42.39 977760.01 0.50 0.01 23.81 6.00 0.10 95.67 42.32 815255.46 0.60 0.01 25.18 7.00 0.12 82.06 42.24 699252.15 0.70 0.01 26.02 8.00 0.14 71.85 42.14 612312.29 0.80 0.01 26.44 9.00 0.16 63.92 42.03 544748.24 0.90 0.01 26.73 10.00 0.17 57.59 41.91 490747.45 1.00 0.01 26.78 11.00 0.19 52.41 41.77 446611.02 1.10 0.01 26.96 12.00 0.21 48.10 41.62 409873.06 1.20 0.02 26.97 13.00 0.23 44.45 41.46 378826.41 1.30 0.02 26.89 14.00 0.24 41.34 41.29 352251.70 1.40 0.02 26.90 15.00 0.26 38.64 41.10 329254.75 1.30 0.02 23.38 Table 4.2 : Efficiency at different angle Using the values of efficiency and the angle of attack from the above table (4.2) a direct relation between efficiency and the angle of attack is obtained which can be seen in the graph below (fig 4.3). Usig a Trendline option in Microsoft Excel an equation of direct relation between angle of attack and efficiency is obtained. The equation shown in the graph is a sixth order equation which is difficult to differentiate to obtained the angle at which the efficiency will be maximum,so a 2nd order equation is obtained from trendline option. Differentiating the equation gives the value of an angle at which the efficiency is max. From this procedure 12 degree is the calculated angle obtained at which the efficiency is max. Fig 4.3: Efficiency Vs. Angle of Attack y = -0.00026 + 0.00785 0.10484 + 0.70883 2.70462 + 6.5617x + 17.369 when x = 12 y = ÃŽÂ · = 25.98 % After substituting the value on angle obtained for maximum efficiency a difference between the two values is found and it is due to the R squared value. More closer the value of R square to unity more accurate results can be obtained. Equations obtained from Microsoft Excel at different orders are shown below:- Order 2 y = -0.12842 + 1.8889x + 20.336 R ² = 0.8797 Order 3 y = -0.00383 0.05482 + 1.4909x + 20.851 R ² = 0.8848 Order 4 y = -0.00524 + 0.13263 1.22762 + 5.2125x + 17.578 R ² = 0.9636 Order 5 y = -0.0015 + 0.02864 0.26813 + 0.86162 + 0.6489x + 20.649 R ² = 0.9869 Order 6 y = -0.00026 + 0.00785 0.10484 + 0.70883 2.70462 + 6.5617x + 17.369 R ² = 0.9945 Similarly using the dimension in table 4.1 (b) the calculated efficiency is show below ÃŽÂ ±(degree) ÃŽÂ ±(radians) W(relative velocity) à Ã¢â‚¬ °(rads/sec) Re Cl Cd ÃŽÂ · 4.00 0.07 143.36 78.24 916231.00 0.40 0.01 53.72 5.00 0.09 114.74 78.13 733319.93 0.50 0.01 58.49 6.00 0.10 95.67 78.00 611441.53 0.60 0.01 61.87 7.00 0.12 82.06 77.85 524439.06 0.70 0.01 63.93 8.00 0.14 71.85 77.67 459234.17 0.80 0.01 64.96 9.00 0.16 63.92 77.47 408561.14 0.90 0.01 65.68 10.00 0.17 57.59 77.24 368060.55 1.00 0.01 65.80 11.00 0.19 52.41 76.99 334958.23 1.10 0.01 66.24 12.00 0.21 48.10 76.72 307404.76 1.20 0.02 66.28 13.00 0.23 44.45 76.42 284119.78 1.30 0.02 66.07 14.00 0.24 41.34 76.10 264188.75 1.40 0.02 66.10 15.00 0.26 38.64 75.76 246941.04 1.30 0.02 57.46 TABLE 4.4: Efficiency at different angles Similarly in this case a graphical representation of Angle of Attack Vs. Efficiency is obtained which can be seen below and the equation represents a direct relation between efficiency and angle of attack. Fig 4.5 : Efficiency Vs. Angle of Attack Order 6 y = -0.00066 + 0.02925 0.62024 + 6.85633 42.0712 + 139.39x 138.43 R ² = 0.9945 when x =12 y = ÃŽÂ · = 64.24% Similarly using the order 2 equation to find the angle at which the efficiency will be maximum. The calculate angle using the same procedure as above is 12 degree at which the efficiency is maximum. . 4.2 Gambiet (Pre Processing):- The figure below shows an impeller of wells turbine designed with blades at 0 degree angle of incidence and using the dimension from the table 4.1 (a). Fig 4.6: Impeller of wells turbine Creating a model using gambiet and then meshing the geometry for which meshing size is selected based on the Reynolds number. Since the Reynolds number lies in the transational flow at the angle in which the efficiency is maximum,using turbulence boundary layer formula: à °Ã‚ Ã¢â‚¬ ºÃ¢â‚¬ ¦ =0.00269 The thicknes of boundary layer is 0.003 m. The mesh size comes to be 0.001m to get three elements in one layer to get fine meshing. In case of 3-Dimensional model the mesh elemet used is Tet/Hybrid. Checking the meshing quality the Aspect Ratio lies between 1 to 4. Boundary conditions is given for impeller is moving wall and interfaces is decided so that the fluid can be rotated within this volume. The mesh is exported for post processing in Fluent 4.3 Fluent (Post Processing) Steps used in fluent is as follows: Step 1 Opening the case file Step 2 Defining the grid interfaces Step 3 Grid check Step 4 Defining model as viscous and using K-epsilon (2 equation ) Step 5 Defining boundary condition In boundary condition fluid within the impeller is made to rotate at 40 rads/sec. The impeller is a moving wall rotating relative to cell zone at 0 rads/sec. Inlet velocity is 10 m/sec and the turbulence method selected is intensity and hydraulic cylinder. Step 6 Solution is converged after ilteraion 5 RESULTS AND DISCUSSION: The results shown below contains pressure contours, velocity vectors and pathlines at different cros-section of the models designed using the dimension from table 4.1 (a). Model with blades at 0 degree angle of incidence and inlet flow from top Model with blades at 0 and 2 degree(+) angle of incidence and inlet flow from top Model with blades at 0 and 2 degree(+) angle of incidence and inlet flow from bottom Model with blades at 2 degree(+) angle of incidence and inlet flow from top Model with blades at 2 degree(+) angle of incidence and inlet flow from bottom Biplane models Model with blades at 0 degree angle of incidece and inlet from top Model with blades at 0 degree angle of incidence and inlet flow from bottom Model with blades at 2(+)and 2(-) degree angle of incidence and inlet flow from top Model with blades at 2(+)and 2(-) degree angle of incidence and inlet flow from bottom Model with blades at 0 degree angle of incidence and inlet flow from top Model with blades at 0 and 2 degree(+) angle of incidence and inlet flow from top Model with blades at 0 and 2 degree(+) angle of incidence and inlet flow from bottom Model with blades at 2 degree(+) angle of incidence and inlet flow from top Model with blades at 2 degree(+) angle of incidence and inlet flow from bottom Biplane models Model with blades at 0 degree angle of incidece and inlet from top Model with blades at 0 degree angle of incidence and inlet flow from bottom Model with blades at 2(+)and 2(-) degree angle of incidence and inlet flow from top Model with blades at 2(+)and 2(-) degree angle of incidence and inlet flow from bottom Comparing the above graphical results under a range of 0-400 for comparison except the last two model. The table below shows the value of dynamic pressure (max) in Pascals of above design. From the table it can be seen that the introduction of two rows provides a better result in terms of dynamic pressure. After giving the installatoin angle the maximun dynamic pressure obtained is 1176 pascals by which we can say that the two rows impeller with and an installaition angle is better than the single rows . Assumptions: Various assumptions made to carry out the simulation is as follows: PATHLINES OF PARTICLES ON IMPELLER: AOA 0 INLET FROM TOP AOA 0 AND 2 DEGREE INLET AT TOP AOA 0 AND 2 DEGREE DEGREE INLET AT BOTTOM AOA 2 DEGREE INLET AT TOP AOA 2 DEGREE INLET AT BOTTOM TWO ROWS AOA 0 DEGREE INLET AT TOP AOA 0 DEGREE INLET AT BOTTOM AOA +2 -2 DEGREE INLET AT TOP AOA +2 -2 DEGREE INLET AT BOTTOM The results shown below is of the dimension used from table 4.1 (b). modelling of the wells turbine is divided into two parts theoretical and practical

The Ebola Virus :: Ebola Hemorrhagic Fever

The Ebola Virus INTRODUCTION The most deadly killers on this earth are too small to see with the naked eye. These microscopic predators are viruses. In my report, I will answer many basic questions concerning one of the fastest killing viruses, the Ebola virus. Questions such as "How does it infect its victims?", "How are Ebola victims treated?", "How are Ebola outbreaks controlled?" and many others related to this deadly virus. GENERAL INFORMATION The Ebola virus is a member of the negative stranded RNA viruses known as filoviruses. There are four different strains of the Ebola virus - Zaire (EBOZ), Sudan (EBOS), Tai (EBOT) and Reston (EBOR). They are very similar except for small serological differences and gene sequence differences. The Reston Strain is the only one which does not affect humans. The Ebola virus was named after the Ebola river in Zaire, Africa after its first outbreak in 1976. STRUCTURE When magnified by an electron microscope, the ebola virus resembles long filaments and are threadlike in shape. It usually is found in the form of a "U- shape". There are many 7nm spikes which are 10nm apart from each other visible on the surface of the virus. The average length and diameter of the virus is 920nm and 80nm. The virons are highly variable in length (polymorphic), some attaining lengths as long as 14000nm. The Ebola virus consists of a helical nucleocapsid, which is a protein coat and the nucleic acid it encloses, and a host cell membrane, which is a lipoprotein unit that surrounds the virus and derived form the host cell's membrane. The virus is composed of 7 polypeptides, a nucleoprotein, a glycoprotein, a polymerase and 4 other undesignated proteins. These proteins are synthesized by mRNA that are transcribed by the RNA of the virus. The genome consists of a single strand of negative RNA, which is noninfectious itself. The order of it is as follows: 3' untranslated region, nucleoprotein, viral structured protein, VP35, VP40 glycoprotein, VP30, VP24, polymerase(L), 5' untranslated region. HOW IT INFECTS Once the virus enters the body, it travels through the blood stream and is replicated in many organs. The mechanism used to penetrate the membranes of cells and enter the cell is still unknown. Once the virus is inside a cell, the RNA is transcribed and replicated. The RNA is transcribed, producing mRNA which are used to produce the virus' proteins. The RNA is replicated in the cytoplasm and is mediated by the synthesis of an antisense positive RNA strand which serves as a template for producing additional Ebola genomes. As the infection progresses, the cytoplasm develops "prominent inclusion bodies" which means that

How to write an essay? Essay

Writing an essay Define the context of your essay. The context is the scope of the essay. What are you being asked to write about? The context can include multiple parameters including: Topic. Sometimes your teacher or professor will give you a prompt that you’re required to use. If you do get an option to pick your own topic, then choose something that you genuinely want to become an expert about or something you feel passionate about discussing. Format. The length of the essay, the way the pages are put together and the presentation all matter. Follow the rules exactly as your teacher gives them to you so that you don’t lose points. Audience. With whom are you trying to communicate? Do you want to persuade your teacher, your peers or a college admissions committee? You’ll need to tailor your writing to the correct audience. Types of Essays Narrative Narration is telling a story from a certain viewpoint, and there is usually a reason for the telling. All narrative essays will have characters, setting, climax, and most importantly, a plot. The plot is the focus of the story and is usually revealed chronologically, but there are sometimes flash forwards and flash backs. In writing a narrative essay, remember to: Include sensory and emotional details, so the reader will experience the story, not just read about it Have the story support the point you are making, and make reference to that point in the first sentence. Write in the first or third person Descriptive Descriptive essays have text which describes traits and characteristics of people, objects, events, feelings, etc in intricate detail. Whatever is being described will be thoroughly examined. For example, if you were describing roses, you would explain: Where they come from What they look like What colors they are How they grow and smell When you write a descriptive essay, you want to involve the reader’s senses and emotions. For example, you could say, â€Å"I got sleepy† or describe it like this, â€Å"As I was waiting for Santa, my eyelids began to get heavy, the lights on the tree began to blur with the green branches, and my head started to drop.† The second sentence gives vivid details to make the reader feel like he is there. Exposition Expository essays can compare, explore and discuss problems, or tell a story. An exposition essay gives information about various topics to the reader. It: Informs Describes Explains In writing an exposition, the text needs to: Be concise and easy to understand Give different views on a subject or report on a situation or event Explain something that may be difficult to understand as you write your essay. Remember that your purpose is to explain. Argumentative In an argumentative essay the writer is trying to convince the reader by demonstrating the truth or falsity of a topic. The writer’s position will be backed up with certain kinds of evidence, like statistics or opinions of experts. The writer is not just giving an opinion, but making an argument for or against something and supporting that argument with data. To know how to write an essay in an argumentative way, you have to research and backup what you say in the text. Learn by Example When learning how to write an essay, sometimes the best way to learn is to look and analyze essay examples. Following are excerpts from narrative essays: â€Å"Looking back on a childhood filled with events and memories, I find it rather difficult to pick on that leaves me with the fabled â€Å"warm and fuzzy feelings.† As the daughter of an Air Force Major, I had the pleasure of traveling across America in many moving trips. I have visited the monstrous trees of the Sequoia National Forest, stood on the edge of the Grande Canyon  and have jumped on the beds at Caesar’s Palace in Lake Tahoe.† â€Å"The day I picked my dog up from the pound was one of the happiest days of both of our lives. I had gone to the pound just a week earlier with the idea that I would just â€Å"look† at a puppy. Of course, you can no more just look at those squiggling little faces so filled with hope and joy than you can stop the sun from setting in the morning. I knew within minutes of walking in the door that I would get a puppy†¦ but it wasn’t until I saw him that I knew I had found my puppy.† â€Å"Looking for houses was supposed to be a fun and exciting process. Unfortunately, none of the ones that we saw seemed to match the specifications that we had established. They were too small, too impersonal, too close to the neighbors. After days of finding nothing even close, we began to wonder: was there really a perfect house out there for us?† The following is an example of a famous narrative written by John Updike, â€Å"Hub Fans Bid Kid Adieu†: â€Å"The afternoon grew so glowering that in the sixth inning the arc lights were turned on–always a wan sight in the daytime, like the burning headlights of a funeral procession. Aided by the gloom, Fisher was slicing through the Sox rookies, and Williams did not come to bat in the seventh. He was second up in the eighth. This was almost certainly his last time to come to the plate in Fenway Park, and instead of merely cheering, as we had at his three previous appearances, we stood, all of us, and applauded.† Following are excerpts from descriptive essays: â€Å"Like his twisted feathers, his many scars, the reliable old owl chose the gnarled, weather-beaten, but solid branch often—it being a companion to the wise alone with the night and the last branch to creak in the heaviest wind. He often came to survey the fields and the clouds before his hunt, to listen to the steady sound of the stream passing through reeds under the bridge, while combing his feathers for the unwanteds—whatever they might be.† Here is a descriptive essay about a first visit to a favorite diner written by a student at Roane State Community College:†When entering the door at Lou’s, two things are immediately noticeable: the place is rarely empty and seems to consist of a maze of rooms. The first room, through the door, is the main part of the restaurant. There is another, rarely used, dining room off to the right. It was added during the oil well boom of the seventies. Through the main dining room is yet another room; it guards the door leading into  the kitchen. This room contains the most coveted table in the place. The highest tribute Lou can bestow on anyone is to allow them access to seats at this table. This table is the family table; it is reserved for Lou’s, and her daughter Karen’s, immediate family and treasured friends.†