Two Stroke And Four Stroke Engine

Two Stroke And Four Stroke Engine To understand the differences between a two stroke and four stroke engines, we need to know how the four stroke engine works. In four stroke engine there are four stages: Intake: The piston travels down the cylinder while the intake valve is opened to allow a mixture of fuel and air to enter the combustion chamber. Compression: The intake valve is closed and the piston travels back up the cylinder compressing the gasses. Combustion: The spark plug ignites the compressed gas causing it to explode, which forces the piston down. Exhaust: The piston rises up the cylinder as the exhaust valve is opened, allowing the piston to clear the chamber to start the process over. Each time the piston rises and falls it turns the crankshaft that is responsible for turning the wheels. This is how fuel is converted into forward motion. The spark plug doesnà ¢Ãƒ ¢Ã¢â‚¬Å¡Ã‚ ¬Ãƒ ¢Ã¢â‚¬Å¾Ã‚ ¢t fire in each revolution but instead fires once every other revolution. A camshaft must alternately tip a rocker arm attached either to the intake or exhaust valve. The rocker arm returns to its closed position according to the movement of a spring. The valves must be seated properly in the cylinder head to avoid compression leaks. Now that the four stroke engines mechanism is explained, it is inevitable to learn about the two stroke engine. The main difference between the two engines is that all four stages in the four stroke engine are integrated into only two phases, one downward stroke, and one upward stroke. Intake and exhaust are both integrated into the compression and combustion movement of the piston, eliminating the need for valves. This is accomplished by an inlet and exhaust port in the wall of the combustion chamber itself. Induction: the piston travels down the cylinder head, and it applies suction to the air-fuel mixture and exerts it into the cylinder. Compression: as the piston travels up to the top of the cylinder head, it applies pressure to the air-fuel mixture from the inlet port in the top of the cylinder head, making the air-fuel mixture ready for igniting by the spark plug. Ignition: the spark plug ignites the pressurized air-fuel mixture (otherwise known as the compressed air-fuel mixture), sometimes referred to as the power stroke. Exhaust: as the piston returns back to the top of the cylinder head after the air-fuel mixture has been ignited, the piston pushes the burnt gases out of the cylinder and through the exhaust system. Transfer Port: The port in a two stroke engine that transfers the air-fuel mixture from the bottom of the engine to the top of the cylinder. two-stroke-exhaust.gif 0003EDA6CENGIZ B9A1592C: Fig2: 2-Stroke engine After the fuel and air experience a relatively small explosion, the piston is driven down to the bottom of the stroke where the exhaust port is uncovered. Most of the gases are driven out in this phase. This process is easily seen with an outboard motorboat, evident by the multicoloured oil slick surrounding the engine, but it happens with all two stroke engines, which is considered one of the disadvantages that makes a designer overlook the use of a two stroke engine in their design. And that is because this process itself (along with burning oil) creates pollution and fuel efficiency issues. Development The idea to build a two-stroke engine goes back to the year 1879. But this engine became a qualitatively good product only after many years, when the German DKW company accelerated its development. Because of its disadvantages compared with the four-stroke engine, the two-stroke engine is used practically just in a small range of capacity, e.g. in small motorcycles considering that the processes involved in the two stroke engine only require the use of a small amount of parts and chambers, and that is why they are used in small applications. Formerly the engine was even used to power tiny cars. The main disadvantage of the two stroke engine would be the loss of fuel and oil (as oil is mixed with fuel, or induced with fresh air to lubricate the piston). And this oil is burnt and sent through the exhaust, as some of the fresh mixture would leave the combustion chamber unburnt. This would basically cause more emissions and dirtier exhaust that would damage the catalytic converter. In recent years, the re-appearance of direct fuel injection (as it already existed in diesel, and 1960s petrol Mercedes), is the main cause of this interest. As direct fuel injection (meaning the fuel injector would be in the combustion chamber such as the spark plug, and would induce the fuel directly in there, as opposed to standard injection where fuel is induced in the intake manifold on top of the valve). This direct injection would limit the fresh mixture loss in exhaust. The thermal post combustion: there is an air pump, called secondary air pump, pumping fresh air into the exhaust when engine is cold. As on cold starts you have a very rich mixture, meaning raw fuel leaving through the exhaust. The fresh air induced, along with the high temperatures of the exhaust, would cause the fuel in exhaust to burn, this would render the emissions cleaner, and would heat up the exhaust faster for the catalytic converter and oxygen sensors to work (as catalytic converters and oxygen sensors need temperatures around 600 degrees C to operate and clean the emissions). This thermal post combustion would clean the remaining raw fuel or hydrocarbons, and heat the catalytic converters and oxygen sensors, so they always work at optimal temperatures. Problems of the two-stroke engine Actually, the two stroke engine should perform twice the performance of a four stroke engine with the same cubic capacity. Although it is just possible to gain a performance that is about 50% better, but still the reasons are obvious; the cylinder cannot be filled up with the same amount of fuel as in the four-stroke engine, because the individual strokes are separated not so clearly which will reduce the amount of space and eventually reduce the capacity for carrying more fuel. If more fuel is induced, it leaves the combustion chamber through the ejection pipe without being burnt. Many concepts were developed to provide a better expulsion of the exhaust in way that the fresh gas doesnt leave the combustion chamber. Though all these inventions, the filling of the two-stroke engine is always worse than in the four-stroke engine, which loses fresh fuel only because of the overlap of the valve times (both valves are open for an instant). Beside these performance-technical problems, ther e are also increasing difficulties with the environment. The fuel mixture of the two-stroke engine often gets shifted with a certain quantity of oil because of the necessary lubrication. Unfortunately the oil gets burnt partly, too, and harmful gases are expulsed by the engine. Two stroke engines already have a lot of advantages over the standard four stroke engines Two-stroke engines do not have valves, which simplifies their construction and lowers their weight. Two-stroke engines fire once every revolution, while four-stroke engines fire once every other revolution. This gives two-stroke engines a significant power boost. Two-stroke engines are lighter, and cost less to manufacture. Two-stroke engines have the potential for about twice the power in the same size because there are twice as many power strokes per revolution. Disadvantages of 2 Stroke Engines: -Two-stroke engines dont live as long as four-stroke engines. The lack of a dedicated lubrication system means that the parts of a two-stroke engine wear-out faster. Two-stroke engines require a mix of oil in with the gas to lubricate the crankshaft, connecting rod and cylinder walls. Two-stroke oil can be expensive. Mixing ratio is about 4 ounces per gallon of gas: burning about a gallon of oil every 1,000 miles. Two-stroke engines do not use fuel efficiently, yielding fewer miles per gallon. Two-stroke engines produce more pollution from: 1- The combustion of the oil in the gas. The oil makes all two-stroke engines smoky to some extent, and a badly worn two-stroke engine can emit more oily smoke. 2- Each time a new mix of air/fuel is loaded into the combustion chamber, part of it leaks out through the exhaust port. http://www.deepscience.com http://www.whitedoglubes.com http://www.atzonline.com/index.php;do=show/site=a4e/sid=10470432604d6722a19884c564334027/alloc=3/id=829

Seasonal Variation in the Western Himalayan Basin

2.1 THE STUDY AREA Beas River In this survey, Beas Basin located in western Himalaya has been selected. Two sites viz. Manali and Bhunter were being selected for appraisal of the part of different constituent i.e. snow/ice melt overflow, rainfall overflow and land H2O overflow to Beas River. Study was besides conducted for the Parvati River at Bhunter site. Beas River originate from the eastern inclines of Rohtang base on balls of Himalayas at an lift of 3900 m and flows in about north-south way up to Larji, where it takes a about right angle bend and flows towards west up to the Bhunter. The length of the river up to the Bhunter is 80 kilometer. The catchment of the Beas basin up to Bhunter is 3384 kilometer2out of which merely 780 kilometers2is under lasting snow. Largely the catchment country comprises of hasty inclines and the stones are chiefly au naturel. The basin height varies from 1600 m near Bhunter to more than 6000 m near Beo-Toibba. Parvati is one of the major feeder which join the Beas River at Bhunter. It rises from Mantalai glacier at an height of about 5200 m ASL. Mantalai glacier is located on the western incline of the great Himalayan ranges. The basin lies between 31050 ‘ to N and 7705 ‘ to E. It drains an country of about Km2. The Parvati River basin is a hilly and cragged piece of land with altitude runing from 1096 to 6250 metres ( Figure ) . The basin presents an interact mosaic of mountain scopes, hills and vales. The mountain inclines in the basin are covered with woods and hayfields. The vales are interspersed with legion watercourses like Malana nal, Tos Nal, Kasol Nal etc. fall in the Parvati River from left and right Bankss. Some of the of import scopes of the basin are Chandrakhari Dhar, Sharkandi Dhar, Rorung Dhar, Phagachi Dhar, Rajthathi Dhar, and Ori Dhar. Western Himalaya: Western Himalaya stretches for approximately between in the E and in the West embracing an country of about sq kilometer. The mean height ranges between 600 to 6900 metre above average sea degree ( Fig ) . The outstanding characteristics include the snow clothed extremums, â€Å" U † shaped vale, truncated goads with snow-off facies, aretes, horn, pyramidal and conelike extremums, serrated cresta of ridges, corries, glacial troughs both ancestor and consequent, knife-edged precipice, smooth stone and steep head-walls. Dhauladhar, Pir-Panjal, Great Himalaya and Zanskar are the chief mountain scopes of the country ( Fig. ) . The Dhauladhar scope bases in all stateliness over the Kangra vale while the Pir-Panjal, Great Himalaya and Zanskar ranges bases land over Chamba, Lahul and Spiti and Kinnaur. The low scopes of Siwalik autumn in the south-western portion. From south to north four good defined tectonic-cum-physiographic belts with distinguishable geological formations have been recognized in the Himachal Himalaya as the outer or bomber Himalaya, Lesser Himalaya, Great Himalaya and Tibetan or Tethys Himalaya. Outer Himalaya is situated in the southern most portion and it has an mean tallness of 600 m the average sea degree. This late Tertiary sedimentary belt fundamentally forms series of drops with steep inclines on the southern side. Lesser Himalaya, caught between the outer Himalaya in the South and Greater Himalaya in the North has an mean lift of 4000 m to 5000 m above average sea degree. The two major scopes viz. Dhauladhar and Pir-Panjal, tendency in NW-SE waies, ( about parallel to the regional tendency of the stone formation ) constitute the chief H2O divide of the part ( Figure- western Himalaya ) . The northern belt of the Great Himalaya, with its extremums surging highs of 5000 m to 6000 m ( amsl ) , is characterized by hasty scarps and perpendicular walled gorgeous vales with toppling and frothing rivers. The eastern extension of the Great Himalaya commences from Nanga Parbat in the West. The Pir-Panjal articulations this scope ( Great Himalaya ) near Deo-Tibba ( 5540 m ) . Chandra-Bhaga ( Lahaul and Spiti ) vale, with heavy snow bound countries, lies between these two scopes. The rugged topography of the country therefore houses maximal glaciers, which range in length from 3 to 35 kilometer. The Satluj river forms a narrow and deep gorge and cuts across the Great Himalayan scope. This scope acts as a great H2O divide between the Spiti and Beas drainage systems. The most critical base on ballss of this scope are located near Darang ( 5,548 m ) , Kangra ( 5,248 m ) , and Rohtang ( 4,043 ) and are on the Pir-Panjal Range. To the E of Great Himalaya is the Zanskar scope that separates the Tibetan basin ( term basin denoting here as a geomorphic entity ) from Himachal Himalaya. The Tibetan basin is connected with the satluj basin of Himachal through base on ballss of Sholarung and Gumarang situated on the Zanskar scope. The river Satluj cuts this scope through a gorge at Shipki ( 6,570 m ) . The Satluj basin is rugged in nature and snow edge and the vale crosses the Great Himalayn ranges near China boundary line and Kalpa ( Kinnaur ) . The general height scope from 4,500-6,500 m, of which the Kinner Kailash ( 6473 ) forms the highest extremum. The intricate moasic forms of hills, mountains and vales all over the province is the feature of the survey country. There is general addition in lift from West to east and south to north. 2.2 Geology of the Himachal Himalaya Geological Survey of India initiated about the geological surveies of Himachal Himalaya every bit early as 1860. Medlicott ( 1864 ) ; McMohan ( 1877, 1895 ) ; Oldham ( 1887, 1893 ) , Hayden ( 1904 ) ; Diener ( 1912 ) ; Pilgrim and West ( 1928 ) and Auden ( 1934 ) are the few innovator workers of this part. The important part to the geology of Himalaya in subsequent old ages have been added by Wadia ( 1931 ) ; Gansser ( 1964, 1977 ) ; Heim and Gansser ( 1975 ) ; Fuchs ( 1967,1975 ) and others. The recent work by Bhargava ( 1972a, 1975,1977b, 1979 ) ; Srikantia and Bhargava ( 1974,1976 ) , Gupta and Kumar ( 1975 ) , Srikantia ( 1981,1982 ) , Sorkhabi. , 1996, Fuchs. , 1981 is an effort to ease out some of the jobs of Himalaya, but most important work chiefly on jobs related to biostratigraphy, lithology, construction and tectonics has been carried out by Valdiya ( 1970,1973 ) ; Bhattacharya and Niyogi ( 1971 ) ; Kumar ( 1971,1978a,1979 ) ; Kumar and Pande ( 1972 ) ; Sinha ( 1975,1977,1 978 ) ; Virdi ( 1976 ) ; Fuchs and Sinha ( 1978 ) , Thakur ( 1980,1981 ) ; Thakur et al. , ( 1991 ) ; Pande ( 1991 ) . The geological set up of the Himachal Pradesh is taken after Thakur et.al. , ( 1991 ) ( Fig ) . 2.3 CLIMATE AND SEASONAL VARIATION IN THE STUDY BASIN The clime is characterized by a short period of mild summer with a well terrible long winter. It has humid, sub-tropical clime in the southern low land countries, temperate in the Lesser Himalayan vales and cool ( sub-alpine ) in higher mountains. Snow-falls occur upto a tallness of 1,300 m during the winters whereas above 4,000 m the countries are under lasting snow screen. The survey country experiences a terrible winter season characterized by the happening of heavy snowfall ( Fig.Snowfall Variation figure of the basin ) at higher heights. India Meteorological Department ( IMD ) has categorised the whole twelvemonth into four season under Indian conditions. January to March is classs under winter season, April to June as summer season, July to September in monsoon season and October to December is Chactgarized as fall season ( post monsoon months ) . Seasonal fluctuation in footings of month may change  ± 15 yearss. 1 ) Summer Season AMJ ( April?June ) Climate In summer season, temperature starts to increase in Himalayan part similar to the other parts of India. Intensity of increasing the temperature is less as comparison to kick and peninsular India. April to June months are considered as summer months in Himalayan part. These 3 months are considered as theodolite period between winter and monsoon season. Weather in Himalayan part sometimes influenced by electrical storms associated with rain during the summer season. 2 ) Monsoon Season JAS ( July-September ) Over the India, monsoon rains begin towards the really terminal of may or the first hebdomad of June over the utmost southern parts of the peninsula and ranges by terminal of June or starting of July in the Himalayan part. It varies from less than 75 yearss over Rajasthan, to more than 120 yearss over the south-western parts of the state lending to about 75 % of the one-year rainfall ( IMD 2010 ) . The parts which receive the largest rainfall are along the west seashore of India and the provinces of Assam and west Bengal in northest India. South west monsoon usually starts over the Kerala seashore. The subsequent advancement of the monsoon may be convenientially traced in the signifier of two subdivisions, viz. , the Arabian Sea subdivision and the Bay of Bengal subdivision. The Arabian Sea subdivision bit by bit advances due norths to Mumbai by 10 June. In the interim, reaching of the Bay of Bengal monsoon over eastern portion is being observed. By mid June the Arabian Sea subdivisi on spreads over Saurashtra-Kutch and the cardinal parts of the state. Thereafter, the deflected current from the Bay of Bengal and Arabian Sea subdivision of the monsoon tend to unify into a individual current. The staying parts of west Uttar Pradesh, Haryana, Himachal Pradesh, eastern half of the Rajasthan see their first monsoon showers by the first of July. The monsoon is influenced by planetary and local phenomenon like El Nino, northern hemispheric temperatures, sea surface temperatures, snow cover etc. The monsoonal rainfall oscillates between active enchantments associated with widespread rains over most parts of the state and interruptions with small rainfall activity over the fields and heavy rains across the foothills of the Himalayas. Heavy rainfall in the cragged catchments under ‘break’ conditions consequences deluging over the fields. However, really uncomfortable conditions due to high humidness and temperatures is the characteristic associated with the Breaks. SW monsoon current becomes lame and by and large starts retreating from Rajasthan by 1stSeptember and from north-western parts of India by 15ThursdaySeptember. It withdraws from about all parts of the state by 15ThursdayOctober and is replaced by a northern continental air flow called North-East Monsoon. The withdrawing monsoon air currents cause occasional showers along the east seashore of Tamil Nadu, but rainfall decreases off from coastal parts. 3 ) Post monsoon OND ( October-December ) Post monsoon season is the driest period in the Himalaya. Rivers of cragged part is by and large sustained by base flow during this period. Southern provinces of India viz. Andhra Pradesh, Telungana, Kernataka, Kerala receive good sum of rainfall accounting for approximately 35 % of their one-year sum in these months. ( IMD study ) . Daily temperature starts falling all over the state. The average temperatures over western Himalaya diminution from approximately 320C to a scope of 15-180C in the month of November. Less humidness and clear sky over the most portion of the North and cardinal India after mid-October are features characteristics of this season ( IMD,2010 ) . 4 ) Winter Season JFM ( January to March ) January to March months are considered as winter season in India. This season starts in December holding clear skies, low temperature, big daytime fluctuations of temperature. In this season rain is by and large occur over the western Himalayas, the utmost north-eastern parts, Tamil Nadu and Kerala. Precipitation during this season is occurred in signifier of rainfall every bit good as in solid signifier as snow in high height parts. This is governed by the extratropical conditions system of mid-latitude part arising from Caspian sea and traveling eastward. This winter conditions system is known as western perturbations and attack India from the West through Iran, Afgansitan and Pakistan. Western perturbations and associated trough in westerlies are chief rain bearing system in northern and eastern parts of the state. Precipitation signifier in the Himalaya is based on the height. , In greater Himalaya, snowfall is the lone signifier, snow and rain in the in-between Himalayas and light to chair rain over the outer Himalayas. Average frequence of the precipitation is approximately 5 to 6 each months and lessenings as season progresss towards the terminal.

Counseling Scenario

The second scenario involves children in a divorce counseling group. It is expected that emotions can and will be stirred. Surprisingly, my co-leader became angry at one of the children after the latter described how angry she is at her mother. My co-leader reacted by comparing the child with her daughter and the child’s mother to another â€Å"victim†. The reaction of my co-leader is certainly uncalled for and is beyond our professional limits as counselors. Nevertheless, there are several ways in handling the situation. The most immediate step that can be done is to control the situation. This can be achieved by directly intervening and talking things down. I can explain to the child that my co-leader has also been in the same situation as hers and that, as a consequence, her feelings can go off as well. On the other hand, I will also tell my co-leader that we should be professional in dealing with the children. I will explain to her that much is expected from us as counselors, and that we should not let our personal circumstances cloud our judgment. I will further remind her that the reason why we are counseling the children in the first place is because they need counseling and because we are in a better position to understand their experiences. It is said that â€Å"to behave in ways which are destructive to oneself or others is not only distressing and disturbing, but also ethically inadmissible† (Callender, 1998, p. 77). This particularly applies to counselors. Ethical guidelines should always be kept in mind so that counselors will act appropriately with respect to their clients (Voskuijl and Evers, 2007). It is important for us, counselors, to bear in mind our professional responsibilities. We should not let our emotions and personal circumstances get in the way of our responsibilities towards others. My co-leader should learn from the ethical guidelines of being a counselor or from plain moral sensibilities.

Health and Social Care L3 Unit 618 Essays - 867 Words

Unit 618 Understand mental well-being and mental health promotion. Outcome 1 1. As individuals are all different, they can respond to the same situation differently. In the same way, individuals can view and cope with their mental well-being and mental health differently. Someone with a negative view of their own situation may feel that they are to blame or not accept the consequences of their actions, they may find it difficult to deal with their own mental health and well-being. A positive individual may cope better with factors affecting their mental health and well-being. They may deal with their mental state in a more pragmatic way. 2. There are a range of factors which may influence mental well-being and mental health problems†¦show more content†¦Socially valued roles and support should mean groups or communities are equipped to cope with mental health issues. Outcome 2 1. An individual can take steps to promote their mental well-being and mental health. These steps could be social connections, being active, learning and developing themselves, social involvement and self awareness. Connecting with other people and developing relationships are important for an individual’s mental well-being. Staying active can help maintain a positive mental state. Learning new skills can create a sense of achievement and improve self esteem. Involvement in the local community or other social groups can develop strong social inclusion encouraging mental well-being. Being aware of own feelings and emotional state means an individual can maintain their mental well-being. 2. It is important to support an individual in promoting their mental well-being and mental health. When offering support it is important to be patient, understanding and accepting. Talking to the individual can provide an insight into what they are going through and offering advice based on their current state of mind. Researching different mental health issues and offering resources to the individual can help them to develop new strategies to cope. 3. When supporting an individual to promote their mental well-being and mental health, there are different strategies to use. One strategy could be to involve them in activities such as trips out, arts and