1. Differentiate the operation and function of Gas and Steam TurbineSteam turbines rotate in the currents caused by the hot water vapour. They form part of a closedwater cycle in which water condenses and is then heated until it evaporates again. Steam turbinestherefore do not come into contact with the fuel deployed and work at temperatures between 500and 50 !". Several steam turbines are often arranged in a row so that # configured for high$medium and low pressure # they are able to optimally convert the respective steam pressure intorotational movement.%sitsnamesuggests$ asteamturbineispoweredbytheenergyinhot$ gaseoussteam&andworkslikeacrossbetweenawindturbineandawaterturbine. 'ikeawindturbine$ it hasspinning blades that turn when steam blows past them( like a water turbine$ the blades fit snuglyinside a sealed outer container so the steam is constrained and forced past them at speed. Steamturbines use high)pressure steam to turn electricity generators at incredibly high speeds$ so theyrotate much faster than either wind or water turbines. *% typical power plant steam turbine rotatesat 1+00#,00 rpm&about 100#-00 times faster than the blades spin on a typical wind turbine$which needs to use a gearbo. to drive a generator /uickly enough to make electricity.0 1ust likein a steam engine$ the steam e.pands and cools as it flows past a steam turbine2s blades$ givingup as much as possible of the energy it originally contained. 3ut$ unlike in a steam engine$ theflow of the steam turns the blades continually4 there2s no push)pull action or waiting for a pistonto return to position in the cylinder because steam is pushing the blades around all the time. %steam turbine is also much more compact than a steam engine4 spinning blades allow steam toe.pand and drive a machine in a much smaller space than a piston)cylinder)crank arrangementwouldneed. That2sonereasonwhysteamturbineswere/uicklyadoptedforpowering ships$where space was very limited.Gas turbines on the other hand rotate directly in the hot combustion gases. 5ith temperatures upto 1500 !"$ these gases are much hotter than those in steam turbines. 6or this reason the bladesare cooled with air that flows out of small openings and creates a 7protective film8 between thee.haust gases and the blades. 5ithout cooling$ the blade material would /uickly wear out. Gas turbines are usedmainlyfor twopurposes. 6irst$ for power production. Second$ forgeneratingthrust forceinanaircraft. 9venthoughfunctionsaredifferent workingprinciplebehindeachcaseisthesame. :erewewill understandhowgasturbineengineisusedforgenerating thrust force in an aircraft.-. 9numerate in potting into operation the propeller shaftThe S;9 stern tube seal system consists of a S;9 aft seal$ an aft bearingbush$ a forward bearing bush and a S;9 forward seal. The S;9 stern tube seals areused for sealing the stern tube at the points where the shaft penetrates. The oil level in the sterntube tank should be , to ? meters above the loaded water)line *'5'0.The aft seal e.ists of three rubber lip seals which are clamped in the house parts. The lipseals are sealing at a corrosion proof liner. The purpose of the aft seal is to prevent *sea0water ingress and oil outlet from the stern tube.The lip seals can be replaced without removing the propeller or withdrawing the propellershaft.ASIAN INSTITUTE OF MARITIME STUDIESPasay City., PhilippinesPOWER 1B 313!3Power 1BActivity 1Submitted by4@ame4 E"erit# Fran$lin E%Student A4 &13!''()Date4 '(*&+*1,Submitted to4-*E ESPE.O=ating4 BBBBBB