Techniques For Airflow Rate Measurements

Techniques For Airflow Rate Measurements My company is setting up an experiment to measure the airflow rate in a duct. Airflow measurement techniques are necessary especially in many industries. Some of the common airflow measuring applications include ventilation testing, air balancing, ductwork, air planes and so on. Many research and studies have been put into improving and inventing new equipments to measure air flow. This is so to enable user to get the most accurate result and at the same time using the least cost. This report outlines the different airflow measurement techniques and devices that are available today. There are many different types and ways to measure air flow but I will concentrate on those that are more popular and commonly used. They are the Pitot-tube, Orifice plate, Venturi meter, Cup anemometer, Sphere anemometer and Hot-Wire anemometer. Techniques and devices for airflow rate measurements 2.1 Pitot tube A pitot-static tube is used in wind tunnel experiments and on airplanes to measure the air flow rate. It is also used in many industrial applications. It was invented by the French engineer Henri Pitot in the early 1700s and was later modified to its modern form in the mid 1800s by French scientist Henry Darcy. It is a slender tube that has two holes on it (Figure 1). The front hole is placed in the airstream to measure whats called the stagnation pressure. The side hole measures the static pressure. By measuring the difference between these pressures, we are able to get the dynamic pressure that can be used to calculate the air velocity. By Bernoullis principle, Stagnation pressure = static pressure + dynamic pressure Solving that for velocity we get: Where V: fluid velocity; pt: stagnation or total pressure; ps: static pressure; à Ã‚ : fluid density Figure 1: Pitot-Static Tube The incorporation of sensors to measure the air temperature, barometric pressure, and relative humidity can further increase the accuracy of the velocity and flow measurements. The Pitot tube can also measure the velocity with the use of a pressure transducer that generates an electrical signal which is proportional to the difference between the pressures generated by the total pressure and the static pressure. The volumetric flow is then calculated by measuring the average velocity of an air stream passing through a passage of a known diameter. When measuring volumetric flow, the passage of a known diameter must be designed to reduce air turbulence as the air mass flows over the Pitot tube. To obtain an estimate of the volumetric flow in the duct from a series of pitot-static tube velocity measurements, one must integrate the velocity over the duct area. There are many of different methods for approximating the above integral. One of the methods is to divide the duct cross-section into a number of equal area sectors, and then measure the average velocity at the center of each sectors. For example, we can divide the cross-section of the duct in the figure below: The velocity will be by calculating the sum: 2.1.1 Advantages and Disadvantages The advantages of using pitot-static tube is that it can be inserted in small airstream and it presents little resistance to flow. It is simple, inexpensive and suited for a variety of environmental conditions including extremely high temperatures and a wide range of pressures. The disadvantages would be that if the flow rate is low, the difference in pressures will be too small to accurately measure with the transducer. If the air flow is high (supersonic), assumptions of Bernoullis equation will be violated and thus leading us to wrong measurement. Furthermore, if the tubes are clogged, the reading by the transducer will be inaccurate resulting in dire consequence in the context on airplane. Icing of the pitot tube had caused plane to crash. 2.2 Orifice Plate Orifice plate is used for flow rate measuring in pipe systems. An orifice plate is placed in a pipe containing a fluid flow, which constricts the smooth flow of the fluid inside the pipe. By restricting the flow, the orifice meter causes a pressure drop across the plate. By measuring the difference between the two pressures across the plate, the orifice meter determines the flow rate through the pipe. Figure 2: Orifice Plate in a duct Applying Bernoullis equation to a streamline flowing down the axis of the tube gives, Where, P: pressure à Ã‚ : density of the fluid V: Velocity of the fluid As shown in the above diagram(Figure 2), point 1 is upstream of the orifice, and point 2 is behind the orifice. It is recommended that point 1 be positioned one pipe diameter upstream of the orifice, and point 2 be positioned one-half pipe diameter downstream of the orifice. Since the pressure at 1 will be higher than the pressure at point 2, the pressure difference will be a positive quantity. From continuity equation, the velocities can be replaced by cross-sectional areas of the flow and the volumetric flow rate Q, Where, A: cross sectional area Solving for the volumetric flow rate Q gives, The above equation remains true with perfectly laminar, inviscid flows. As for real flows like water or air, we have to take into account of the viscosity and turbulence that are present .To account for this effect, a discharge coefficient Cd is introduced into the above equation to marginally reduce the flow rate Q, Since the actual flow profile at point 2 downstream of the orifice is quite complicated, the following substitution introducing a flow coefficient Cf is made, Where, Ao: area of the orifice As a result, the volumetric flow rate Q for real flows is given by the equation, The flow coefficient Cf is found from experiments and is tabulated in reference books. It ranges from 0.6 to 0.9 for most orifices. Since it depends on the orifice and pipe diameters (as well as the Reynolds Number), one will often find Cf tabulated versus the ratio of orifice diameter to inlet diameter, sometimes defined as b, The mass flow rate can be found by multiplying Q with the fluid density, There are mainly 3 different types of orifice plates. They are Concentric, Segmental and Eccentric. This is to accommodate for different applications so that the meter has the optimum structure. The density and viscosity of the fluid, and the shape and width of the pipe do influence the choice of plate shape to be used. The concentric orifice is the most common of the 3 types. In this design, the orifice is equidistant. It is generally used for clean liquid and gas flow in pipes under six inches, where Reynolds numbers range from 20, 000 to 107. We will therefore use concentric orifice for our experiment purposes. ( which deals with air). Segmental orifice is similar to concentric orifice with regard to its functioning. The circular section is concentric with the pipe while the segmental part is mounted in a horizontal pipe. This installation helps to eliminate of foreign materials on the upstream side of the orifice. Eccentric orifice plates are designed in such a way that the edge of the orifice is reallocated towards the interior of the pipe wall. It is used in similar manner as the segmental orifice plate. Figure 3 below shows the different types of orifice plates: 2.2.1 Advantages and Disadvantages With no moving parts and a simple design, the orifice is easily machined. It is low lost and can be easily inserted into a duct or an existing pipeline with a minimum alteration to the layout. Therefore orifice plate has been a popular device for flow measurement. The disadvantage is that it creates a rather large non-recoverable pressure due to the turbulence around the plate, leading to high energy consumption (Foust, 1981). 2.3 Venturi meter Most of the unrecoverable loss of pressure with an orifice is due to the sudden change in the cross sectional area. The sudden increase of area after the air passes the section of minimum area: the rapid convergence of the stream on the upstream side contributes considerably to the total loss. We are able to recover most of the pressure by leading the stream with the use of a conical length of pipe, with its smaller end of the same cross section as the jet, and gradually expanding in size along the direction of flow until the full pipe diameter is reached. An arrangement of this kind, with a conical entry is known as a venturi tube. The Venturi effect is named after Giovanni Battista Venturi (1746-1822), an Italian physicist. A venturi meter consists of a cylindrical length, a converging length with an included angle of 20o or more, and short parallel throat, and a diverging section with an included angle of about 6o. The internal finishes and proportions are designed in such a way to enable us to achieve the most accurate readings while ensuring minimum head losses. Assuming that the fluid is inviscid with no losses due to viscosity, the velocity at section 1 and 2 are V 1 and V 2 respectively. The velocities are steady and uniform over areas A 1 and A 2 Applying Bernoullis equation to a streamline passing along the axis between the two sections ( 1 2 ). Where, V:Velocity of the fluid P: Pressure à Ã‚ : density of the fluid Z: Height Using continuity equation, Q = A1 V 1 = A 2 V 2 When real world effects such as fluid friction and turbulence are included a correction factor, called the coefficient of discharge, Cd is introduced into the venturi equation giving For low viscosity fluids C d = 0,98. 2.3.1 Advantages and Disadvantages The venturi tube introduces substantially lower non-recoverable pressure drops (Foust, 1981). Therefore venture tube can be used on more viscous fluid. However it has limited range ability. It must be used only on installations where the flow rate is well known and varies less than 3 to 1. It is rather expensive and should be flow calibrated to provide accuracy into the range of +/- 1.00%, Units are big and weigh more than comparable head devices and thus making it difficult to install and inspect. 2.4 Anemometer An anemometer, also known as wind vane is a device for measuring the air flow rate in a contained flow such as duct or unconfined flow. The term is derived from the Greek word anemos, meaning wind. In around 1450, the Italian art architect Leon Battista Alberti invented the first mechanical anemometer which consisted of a disk placed perpendicular to the wind. To determine the velocity, an anemometer detects change in some physical property of the fluid or the effect of the fluid on a mechanical device inserted into the flow. They are probably best used mounted on light, preferably streamlined, supports and inserted into the airstream from one side. 2.4.1 Cup anemometer This device consists of three or four hemispherical cups mounted at the ends of horizontal spokes which rotates about a low-friction vertical shaft. An electrical device is used to record the revolutions of the cups and measures the air flow rate. (Figure below) As the anemometer is placed inside the flow stream, the concave surfaces of the cups have higher wind resistance than their convex counterparts and thus producing an unbalanced moment with respect to the center axis. This forces the cups to rotate (see schematic). Under steady flow condition, the rotational speed of the anemometer is directly related to the wind speed, that is: V=rw. There are number of fundamental physical parameters and characteristics of an anemometer that affects the cup anemometer performance. They are: rotor arm length cup area rotor inertia drag coefficient on convex face of cup drag coefficient on concave face of cup static, dynamic and parabolic mechanical friction coefficients for temperature range sensitivity characteristic to out-of-plane attack linearised calibration curve. A well designed cup anemometer should have the following characteristics as shown in the Figure 4 below: Let us examine a cup anemometer rotating at speed w in a free wind speed U: The instantaneous aerodynamic torque on the rotor, MA, is given by: where A: frontal area of the anemometer r: the air density Cdv : drag coefficients for the concave faces of cup Cdx drag coefficients for the convex faces of cup In the steady state, there is perfect torque balance (MA=0), and the equation reduces to: defining l and  µ as the speed and drag ratios respectively: allows further re-expression in a quadratic form: Typical values of Cdv and Cdx are 1.4 and 0.4 respectively, giving a value of  µ of 3.5. The above equation predicts that the consequential speed ratio l will be 0.303, meaning the rotor will rotate at about one third of the wind speed. Note that this solution also proves the theoretically linear sensitivity of the cup anemometer to wind speed. It also shows that the speed ratio is dependent on the drag characteristics of the cup and not the size. Furthermore, the rotational speed is inversely proportional to rotor radius. 2.4.2 Advantages and disadvantages The advantages of the cups are their reliability and ruggedness. The disadvantages are the relatively high threshold velocity (the minimum wind velocity needed to start the cups to turn). It is mainly used to only measure the horizontal component of the wind. Another problem with cup anemometry is the different response time for increasing and decreasing wind velocities due to its moment of inertia. This results in an overestimation of wind speed under turbulent wind conditions as present in nature, the so-called over-speeding. Additionally, the rotation of the anemometer causes a wear of bearing and leads to a recalibrations with time. 2.5 Sphere anemometer Many research and studies have gone into the improving of such a device (Cup anemometer). For example, the sphere anemometer. It was developed at the University of Oldenburg. This sphere anemometer, as shown in figure 4 below, is able to measure the air flow rate as well as simultaneous detection of the air flow direction. It eliminates the problem of wear of bearing as encountered in cup anemometer. Figure 5: The sphere anemometer uses the relationship between the point force F acting on the tip of a rod and its resulting deflection s. (1) Where l: the length of the rod E: the elasticity modulus Ja: the second moment of area. In case of the sphere anemometer, with a sphere radius r much bigger than the radius of the rod rR, the force can be assumed to act only on the tip. The second moment of area is then given by (2) Together with the force acting on the sphere (3) where cd: the drag coefficient of the sphere A: the cross section of the sphere ÃŽÂ ¡: the density of air V: the wind velocity Equation 1 becomes (4) Therefore the deflection of the rod is proportional to the drag coefficient cd and the wind velocity squared. For a calibration it is necessary to know how the drag coefficient cd changes with wind velocities. Table 1 below shows the drag coefficient of a sphere plotted against the Reynolds number (Re) (cf [1]). It can be seen that for Reynolds numbers in the range from about 800 to 200000 the change in drag coefficient cd is negligible. For a sphere with a radius r = 40mm this range in Re corresponds to a range in wind velocities from 0.17m/s to 38m/s using where v = 1.51 x 10-5 m2/s is the kinematic viscosity of air. Within this velocity range the deflection s of the rod is directly proportional to the wind velocity squared. With this direct relation it is easy to calibrate the sphere anemometer over a wide range of wind velocities. Table 1: 2.6 Hot wire anemometer Thermal anemometry is the most common method used to measure instantaneous fluid velocity. The technique depends on the convective heat loss to the surrounding fluid from an electrically heated sensing element or probe. If only the fluid velocity varies, then the heat loss can be interpreted as a measure of that variable. Working Principle Its principle application is the measurement of rapid fluctuations, particularly the study of turbulent flow; in this field it is the only instrument with sufficiently rapid response, and the associated electronic equipment lends itself readily to signal processing needed to record directly such properties of a turbulence as r.m.s values, correlation functions, and spectral distributions. Governing equation Consider a thin heated wire mounted to supports and exposed to a velocity U Where, W: power generated by Joule heating (W=I2Rw) Q: heat transferred to surrounding Qi: CwTw=thermal energy stored in wire Cw: heat capacity of wire Tw: wire temperature The wire is heated electrically and placed in the flow stream. The energy balance of the heated wire at equilibrium is (equation 1): Where, I: an electric current Rw: the wire resistance h: the heat transfer coefficient A: the heat transfer area Tw: the wire temperature Tf: the fluid temperature D: wire diameter Kf: heat conductivity of fluid Nu: dimensionless heat transfer In the forced convection regime (0.02 Reynolds number: Re= (where r is the air density and U is the velocity and  µ is the air dynamic viscosity).(equation 2) Where Substituted Eq(2) into Eq(1), There are two types of hot-wire anemometer used in practice but I will touch on Constant Temperature Anemometer which is more commonly used. For a case of Constant Temperature Anemometer Where And The voltage is a measured of velocity U. 2.6.1 Advantages and disadvantages It has good frequency response as it can measure up to several hundred kHz possible. It is able to measure a wide range of velocity. It is small in size and has rapid response.- Thermal anemometry enjoys its popularity because the technique involves the use of very small probes that offer very high spatial resolution. The basic principles of the technique are relatively straightforward and the probes are difficult to damage if reasonable care is taken. However, deposition of impurities in flow on sensor can alter the calibration characteristics and reduce frequency response. Probe may or burnt out easily if not carefully taken care of. It is unable to fully map velocity fields that depend on space coordinates and simultaneously on time. Furthermore, it cannot work well in hostile environment like combustion. The wire diameter needs to be very small of the order of 0.02mm or less. Conclusion In this report, I have touched on the different techniques and different devices for the measurement of airflow. There are many different devices in the market but many use similar techniques with abit of new inventions or add ons here and there. Different airflow measuring devices utilize different technologies and thus, one needs to fully understand the characteristics, techniques and its pros and cons before selecting the optimal one for use. In summary, an ideal device to measure air flow rate should have the following characteristics good signal sensitivity. It should be able to detect output for small changes in velocity. High Frequency Response: to accurately follow transients without any time lag Wide velocity range Create minimal flow disturbance Good Spatial Resolution Inexpensive High Accuracy User friendly

Booker T :: essays research papers

BOOKER T WASHINGTON *V* WEB DUBOIS For more than a hundred years important Black leaders such as: Douglass, Elliot, Washington, and Du Bois have been both praised and sensationalized in our (Black) history books for their individual efforts in the struggle for the civil and political advancement of Black Americans; but among all others the two most â€Å"talked† about during that period would have to be Booker T. Washington and his fellow activist and most verbal critic W.E.B. DuBois. Although during the span of their prospective careers both have worked diligently to secure a place for Black Americans in society, agreeing in context with each others hope for the future, in methodology at least their difference of opinion as to the way to go about achieving that goal varied in as many ways as from star to star varies in its positioning in the universe. Both valued and villainized during his time for his controversial proposal on the unification of Black and White America, civil rights activist Booker T. Washington came to be known as a force to be reckoned with after the presentation of his address at the â€Å"Atlanta Exposition† in 1895. In his proposal, under the guise of wanting to say something meaningful that would unite the races, Washington encouraged Black Americans to: 1.settle for low level industrialized education, thereby focusing on the maintenance of the cotton gin instead of the magnitude of their learning potential, 2. Reconcile with the South in a grandiose gesture of forgiveness, which is in my opinion never the less over shadowed by the hundreds of ropes still decorating Worts II the branches of old southern oaks and dogwoods, and 3. Submit to the loss of all aspirations toward acquiring civil and political rights, therefore with that move relinquishing all hope of ever being anything more than they already were. In proposing that blacks initiate this type of voluntary subservience Washington thought that with time and hard work Blacks could build their futures through the accumulation of commerce and with the patronization of private owned businesses in their communities gradually acquiring the basic civil and political appendages owed them. He felt that it was more important to be able to earn a living then to be able to say that they were equal under the law; in other words a jobless man who is able to vote does nothing to contribute to the good of society if he is unable to first contribute to the preservation of his own well being.

A Farewell to Arms by Ernest Hemingway Essay

The key to a good book is a great plot. The plot determines all the events in the story, from the first word, down to the last period. Ernest Hemingway is considered as a giant in the literary world. His book, A Farewell to Arms is a testament to his literary genius. A Farewell to Arms seems at first to be a love story. It is, but most importantly, the novel is a story about war, and the tragedy it brings. In his work, Freylag’s pyramid of narrative structure is clearly shown. Exposition The novel opens with a description of the place where the main character, Frederic Henry or simply called â€Å"Tenente† stayed. He is the narrator of the story. Hemingway illustrates late summer giving details like falling leaves turning into dust. Troops marching and flashes of fighting in the mountains create an atmosphere of doom to the reader. Hemingway prepares the setting by making a contrast of peace in nature and the disturbance brought about by the soldiers; a smaller picture of the bigger chaos that nations are facing in war. The characters are also established early in the novel. The narrator is an American volunteer ambulance driver. In the early part of the novel, he is introduced by a friend to Catherine Barkley, who is the focal point of Henry’s love in the story. Both are the main characters of the story. Others include, Rinaldi, the friend who introduced Henry and Catherine. A typical Italian male. The priest, Helen Ferguson, and other ambulance drivers also make up the characters that made World War I alive for the reader. Rising Action The novel is divided into five books. In the first book, Henry and Catherine are introduced and their relationship begins. The next few books follow the injury of Henry, and his growing relationship with Catherine while convalescing in a hospital in Milan, far from the action. Catherine becomes pregnant and Henry was forced to go back to the front, leaving her. Upon coming back, a retreat was ordered, were all officers were killed but Henry was able to escape. He was marked as a deserter and having found Catherine, travelled by boat to Switzerland. Here, Henry and Catherine lived a quiet life until she goes into labor. All these events, consist of the bulk of the novel. Hemingway had set many problems for Henry and Catherine. He wanted to show that Henry as a hero, was always stoic in adversities. Catherine’s burden started upon being pregnant but was not too much dwelled upon by Hemingway until the final book of the novel. Several conflicts were shown by Hemingway. The most apparent was Henry’s struggle with the tragedies of war. Henry’s friend was shot to death by Italians upon retreat; the killing spree of officers; Henry’s life as a deserter; the difficult escape to Switzerland by a rowboat . All these were the trials of Henry during the war, and what is ironic is that, he wasn’t in danger of the enemy, but of his comrades, of the soldiers that he had been fighting at the same side. These conflicts build up, highlighting the biggest conflict, the Climax. Climax Upon Henry and Catherine’s successful escape to Switzerland, Catherine goes into labor. The labor is long and painful for Catherine. After a Cesarean operation, the baby is stillborn; and Catherine haemorrages and dies. The Climax is the culmination of events which create the peak of the conflict. The above-mentioned scene is considered as the climax because, after all the efforts of Henry and Catherine went through to be together, all has been wasted in Catherine’s death. Falling Action After Catherine died, Henry was left alone with the doctor. He feels helpless and doesn’t want any gestures of comfort. The offers of the doctor to bring him to his hotel fell on deaf ears. After the peak of the climax, events that follow constitute the falling action. In his novel, Hemingway skillfully illustrates the unbearable grief and emptiness left upon the passing away of a loved one. The downward slide of Freylag’s pyramid accurately shows the feeling of the main character upon losing his love. Denoument The conclusion as its name suggests brings an end to the story. In A Farewell to Arms, after Henry went out and left the hospital, he walked back to the hotel in the rain. It is a sad ending that leaves a heavy heart to the reader. The novel is concluded by the image of Henry walking in rain. Rain usually represents gloom and sadness. In his conclusion, Hemingway shows the main character, the hero, no longer stoic but very much in pain. Works Cited Hemingway, Henry. A Farewell to Arms. New York: Charles Scribner’s Sons, 1957. Print. â€Å"A Farewell to Arms† by Ernest Hemingway Essay Hemingway and the Struggle of Masculinity in WarMen in A Farewell to Arms and For Whom The Bell TollsThe name of Ernest Hemingway has long been associated with the idea of a strong, stubborn man who is very socially inept. In both A Farewell to Arms and For Whom the Bell Tolls, we are introduced to an extremely cold, unfeeling character and we see how they evolve from one type of man into another. Frederic Henry and Robert Jordan are both Americans serving overseas in some conflict, Henry being in World War I and Jordan in the Spanish Civil War between the fascists and communists, and they originally see these conflicts as a way for them to prove their manhood. They soon realize that war is not meant for all people and that it should not be glorified. They either die for their new ideas or simply vanish from our world into a realm of nothingness. This transition needs to be analysed more closely in order for us to understand it better. In A Farewell to Arms and For Whom the Bell Tolls, we see how the main character is, in the beginning, a cold and sometimes insensitive person who loves the idea of war. In Arms, we see how Henry is a calm, calculating man who tries to live up to the Western impression of how a man should act. In American history, men have tried to reassociate themselves with a deeper meaning of manhood as a way to prove to themselves that they are acting like a man should: â€Å"A broad spectrum of American men soon came to view war as the only way to cure a hopelessly flagging national masculinity†(Donnell para 35). In the beginning, Henry the confidence of a man who is able to survive anything by himself and not show any emotion about it. War itself is a glorious game to him that is a test of manhood, a way for him to prove himself to the world and still be able to walk away from it: â€Å"Well, I knew I would not be killed. Not in this war. It did not have anything to do with me. It seemed no more dangerous to me than war in the movies† (Arms Detzler 237). Henry is a man who thinks that he is unable to be harmed and tries to live a life that is morally correct while struggling through a chaotic world. The Austrian mountains around Henry are full of temptation(ie bawdy houses) and yet he never visits them. Also, he is surrounded by constant barrages of shellfire and wounded, since he is an ambulance driver, and never shows any emotion towards these men. To him, they are simply chess pieces and he is the ambulance that comes to take away the wounded from this  great game. In Tolls, the main character is an American teacher, Robert Jordan, who is fighting in the Spanish Civil War. He is only in the mountains because he sees war as a glorified game for men only. When he is confronted with a task, such as blowing up a bridge to slow down enemy troop movements, he does not think about it and only focusses on what he needs to do: â€Å"He would not think about that. That was not his business. That was Golz’s business. He had only one thing to do and that was what he should think about and he must think clearly and take everything as it came along, and not worry. To worry was as bad as to be afraid. It simply made things more difficult†(Tolls 8). He distances himself from the men he may have to kill and dehumanises his actions, allowing him to succeed at his job without showing any emotion or weakness. Jordan sees war as a man’s job and that women have no place in it. When he first meets Maria, he tries to hide his feelings for her. He says that she should not be in the mountains with the guerillas and tries to hide how he feels an attraction to her when he looks at her. Jordan sees his emotions as a weakness and buries them deep down inside of himself, only to have them rise up later on in the novel. In conclusion, both Henry and Jordan begin as calm, cool, calculating men struggling to prove to the world who they are. These men live by a strict code of honour, chivalry, honesty, and courage, allowing their soul to survive many tough times. They originally see a war as a way to prove themselves but this soon changes. Detzler 3Towards the middle of both Arms and Tolls, we see how both Jordan and Henry become confused and disoriented by the events around them. They are faced with tough choices and are forced to reevaluate their beliefs. In Arms, Henry is wounded during the Italian retreat and is sent back to a hospital for recovery. There, he sees his helplessness as a sign of his weakness and feels that he should not have been hurt. After recovery, he returns to the front but becomes trapped with few other men from his battle group. After the men refused to help him in their struggle to make it back, Henry shoots them at point blank range in an effort to encourage the men to work harder. After this, Henry himself is almost executed after being  mistaken for an Austrian. His near-death experience during his escape caused him to reassess his beliefs because he is beginning to see that men are not meant to try and slaughter each other. He flees the army and gives in to his desires to see Catherine, a sign that he is going back on his belief that a man should never show any emotion. Henry travels to Switzerland with Catherine and tries to live out a normal life there, but now he is a confused man struggling with internal demons about his actions: â€Å"The war seemed as far away as the football games of some one else’s college. But I knew from the papers that they were still fighting in the mountains. . . .† (Arms 277). Henry still remembers the men that he left behind at the lines and still wishes to be with them, fighting against a common enemy and united through courage, bravery, and the desire to stay alive. In Tolls, Jordan struggles with his ideas of courage and bravery as he is faced with various situations leading up to the destruction of the bridge. At different times, he is tested by other men, such as when he is forced to kill an enemy soldier who is actually just a boy. This action causes Jordan to rethink how war should be fought: should it be a cruel, merciless battle between soldiers and civilians, or should the young and innocent be spared, even if it is a sign of weakness. Also, when El Sordo and his men are trapped by the Fascist Army, they are left alone Detzler 4to fend for themselves, as to not expose the revolutionaries true numbers. Jordan wishes to go and help them because they are his comrades, but if he is to that, then he would be killed because of what some would call courage and what others would call stupidity. He is faced with either death or living a life of shame. El Sordo himself thinks the same as Jordan, wanting to die a glorious death since he knows that he should want to run away from the Fascists: â€Å"Dying was nothing and he had no picture of it nor fear of it in his mind. . . . Living was a hawk in the sky. Livng was an earthen jar of water in the dust of the threshing with the grain flailed out and the chaff blowing.† (Tolls 313). El Sordo does not fear death because he accepts that it is an inevitable part of life. Both Henry and Jordan begin to have second thoughts of their long held beliefs that men should be cold, merciless soldiers and start to wonder if their new ideas about wanting to be afraid are the ones they should listen to guide their lives. At the end of the novels, both Henry and Jordan face death, either directly or indirectly caused by war, and try to cope with it. In Arms, Henry is faced with the death of his wife and child in Switzerland. During child birth, Catherine develops complications and needs to be heavily medicated to numb the pain. Their child is still-born and Catherine soon after dies from massive blood loss. The loss of Henry’s wife forces him to think about how he has lived his life. He begins to wonder if it was worth it shooting those men for refusing to help him. He questions if he should have even joined the army in the first place. Henry even begins to think that perhaps the war is not some game and that even the innocent can be affected by it. He simply retreats back into his own thoughts because he cannot face the world anymore. Henry displays such self control that it cannot be healthy. He is trying to not show any weakness, an idea that he has always held to be true, even though he does not want to glorify war anymore: â€Å"Such illustrious-control is a visible expression of the self-discipline, knowledge, skill, and poise a man must Detzler 5achieve-as well as the honesty, courage, persistence, and stoic endurance he must possess in order to confront the vicissitudes of his life and the inevitability of . . . death on his own terms and with honour† (Miles para 9). Henry develops a strong resolution towards death and does not feel anymore that war, a vast death machine, should be promoted since it can hurt even the most innocent people in the world, such as unborn children. He then proceed to vanish from this world and become like a walking zombie, unable to move on with his life but unafraid of anything anymore that might threaten him since he has already lost what is most precious to him. In Arms, Jordan is faced with death at the end of the novel in many different ways. His friend Anselmo is killed during the bridge demolition while trying to protect Jordan. Anselmo himself did not like death but was willing to face God if it meant the completion of Jordan’s task. Jordan himself is gravely injured while trying to flee from the Fascists and resolves to take out as many as he can before he dies. Jordan does not show any weakness towards his friends, even though he is terrified and wants to run. Jordan changes from seeing death as something far away as something that affects  everyone. It is a chance for Jordan to redeem his past life and try to come to grips with how he sees death and war. He realizes that he has lived his life wrong and that the war that he is fighting in is not the one he thought he would be fighting for. Jordan originally thought that he was fighting to save the Spanish people from the Fascists but he eventually realized he was not fighting to save the people but rather to replace one corrupt leader for another. He then comes to accept that he will die soon and waits for his time on Earth to end, hoping to take an enemy with him when he goes:Dying is only bad when it takes a long time and hurts so much that it humilates you. . . . [T]here is something you can do yet. As long as you know what it is you have to do it. As long as you remember what it is you have to wait for that. Come on. Let them come. Let them come. Detzler 6Let them come! . . . And if if you wait and hold them up even a little while or just get the officer that may make all the difference† (Tolls 468-470). To Jordan, death is an inevitable part of life and now he is dedicated to taking someone down with him. His part in war is over forever but he does not want to just fade away. He understands that war is glorious but if the next man is an enemy, that man is marked for death. Therefore, both Henry and Jordan come to understand death better and to know that war is not a glorious event. War is simply a big political game with the small people taking most of the fall. In conclusion, we see how both Henry and Jordan have changes brought about to their perceptions of war. They originally join their cause simply because it is something that all men were doing at that point in life. War was someplace that boys could go and become men. War was some far off land where men would run towards each other twice, shake hands and become friends again. Henry and Jordan soon see that war is nothing like this, with innocent people being killed simply because they are in the wrong place at the wrong time. Both men evolve from their original selves and change their ideas about life and death. Henry and Jordan lose a part of themselves during their battles, becoming better men in the end. They may be alone in the world but they are better men than they originally were: â€Å"[T]he individual is on his own, like a Pilgrim walking into the unknown with  neither shelter or guidance, thrown upon his own resources, his strength, and his judgement. Hemingway’s style is the style of understatement since his hero is a hero of action, which is the human conditon† (Hallengren para 17) These men, even though sometimes shallow, exhibit many qualities that both genders should live up to: honesty, courage bravery, morality, intelligence, affection, pride and sometimes sentimentality. These are the qualities that allow the two main characters to see through the â€Å"fog of war† and come to the basic conclusion: war is not meant for all people to be involved in and it should not Detzler 7be put up on a pedestal but rather looked upon with a logical mind. Even though peace is a lofty goal, it is very unlikely for humanity to succeed in achieving world peace. Until that day, war will be an everyday aspect to our lives and we need to step back and take another look at it. We need to stop viewing war as a big game and see it as a big political game, one that is not meant to help the little people, just like Henry and Jor dan learned. Works Cited Donnel, Sean M.. Hemingway’s Short Fiction and the Crisis of Middle Class Masculinity. [Online] Available http://www.elcamino.edu/Faculty/sdonnell/hemingway’s_ masculinity.htm , May 12, 2006. Hallengren, Anders. A Case of Identity: Ernest Hemingway. [Online] Available http://nobelprize.org/literature/articles/hallengren/index.html , April 21, 2006. Hemingway, Ernest. A Farewell to Arms. New York: Charles Scribner’s Sons Publishing Company, 1957. – – – – . For Whom the Bell Tolls. New York: Charles Scribner’s Sons Publishing Company, 1968. Miles, Melvin C.. An Introductory Overview to Hemingway. [Online] Available http://www.elcamino.edu/Faculty/sdonnell/hemingway.htm , May 10, 2006.

Eating Disorders And Their Brains - 1301 Words

Eating Disorders In US today, over 30 million men, women, and children suffer from an eating disorder. Research shows that 42% of first- to third-grade girls want to be thinner, and 81% of 10-year-olds are afraid of being fat. In fact, most kids with eating disorders began their disordered eating between the ages of 11 and 13. (Eating Dis.3) The most common eating disorders are; Anorexia, Binge eating, and Bulimia. Why do people resort to something so life threatening? Many people are turning towards eating disorders because they don’t accept who they are. Eating disorders are a mental illness that can have dangerous effects on the human body, and several people are involved in this bad habit. In some cases, people can’t necessarily stop the disorder because it is in their genetics. Other times, it’s the person choice on whether or not they’d like to open this hurtful portal to darkness. Scientists have done many studies on women involved in eating disorders and their brains function different than a healthy woman. Eating disorders aren t just a mental illness, there are a physical illness as well that often destroy the body s normal function. It may start as just starting to eat less or more, but it can have a dramatic effect to your body that it increases and gets worse. People who are going through puberty and changes on facial and body appearances often lean towards eating disorders because they want to be an ideal image that it advertised everywhere in media.Show MoreRelatedEating Disorders : An Eating Disorder1184 Words   |  5 Pagesas an eating disorder. Weir (2016) goes on to explain the origins behind eating disorders in individuals. This topic is important because, in the United States, many women and men suffer from a clinically sign ificant eating disorder at some point in their life. 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We reveal how and why it becomes a problem, and what you c an do about it. It is normal to overeat from time to time, but when it comes to binge eating, the urge is persistent and seemingly uncontrollable, and is usually accompanied by feelings of shame and guilt. Binge eating disorder, justRead MoreEating Disorders : Anorexia Nervosa, Bulimia, And Binge Eating1453 Words   |  6 PagesIn the United States of America 20 million women, and 10 million men suffer from a clinically significant eating disorder at some time in their life. There are three types of eating disorders, Anorexia nervosa, bulimia, and binge eating. Eating disorders can be life-threatening conditions that can affect a person’s physical health, and emotional. Something that serious has people wondering what exactly is causing these people to risk their health on it? 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Treatments that fall into this camp include cognitive behavioral therapy, which addresses a persons thoughts and behaviors about eating and self-image, and interpersonal psychotherapy, which helps a person face and heal rifts in