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  • Heat Exchanger(Alat Penukar Kalor) MCF 41264 (4 SKS)

  • Aljabar Linier (4)

    Kalkulus (4)

    Matematika Teknik (4)

    Mekanika Fluida (4)

    Sistem Instalasi Fluida* (3)

    Mekatronika* (4)

    Semester 1

    Skripsi (6)

    Kimia (2)

    Fisika 1*:Panas & Mekanik (4)

    Material Teknik (4)

    Menggambar Mesin* (3)

    Agama (2)

    Termodinamika Dasar (4)

    Bhs. Inggris (3)

    Olah Raga atau Seni (1)

    Semester 2

    Statistik & Probabilitas (2)

    Menggambar Teknik* (2)

    Perpindahan Kalor dan Masa (4)

    Fisika 2*:Listrik, Magnet, Gel & Optik (4)

    Perancangan Mekanika (6)

    Industrial Safety, H&E (2)

    MKU Terintegrasi (6)

    Kinematika & Dinamika (4)

    Proses Produksi* (5)

    Metrologi & Pengukuran* (3)

    Teknik Tenaga Listrik (2)

    Pengendalian Sistem (4)

    Getaran Mekanis (2)

    Pemilihan Bahan & Proses (4)

    Manajemen Proyek* (3)

    Mesin Konversi Energi* (4)

    Tugas Merancang (4)

    Sistem Pemeliharaan (2)

    Manajemen Sistem Informasi (3)

    Etika & Hukum (2)

    Pilihan 1 s/d 3(12 @ 4)

    Kapita Selekta Industrial (2)

    Kerja Praktek (2)

    Pilihan 4&5(8 @ 4)

    Semester 3

    Semester 4

    Semester 5

    Semester 6

    Semester 7

    Semester 8

    Gambar 3.2.2 Diagram Alir Mata Kuliah Program Studi Teknik Mesin

  • Tujuan Pembelajaran

    Mengenal jenis-jenis alat penukar kalor Mengetahui jenis APK yang paling baik untuk aplikasi industri yang adaMengerti parameter kunci dalam desain APKMampu mengestimasi ukuran dan harga APKMemiliki latarbelakang untuk menggunakan software komersial untuk mendesain APK

  • Pendahuluan Heat Exchangers

    Untuk apakah Alat Penukar Kalor?Jenis-Jenis Alat Penukar KalorBagaimana Alat penukar kalor diklasifikasikan?Dasar-dasar perencanaan Alat Penukar Kalor?

  • ContentsMengapa kita membutuhkan APKKonstruksi APKMacam-macam APKProses Desain APK

  • Apakah fungsi APK itu ?Untuk memperoleh aliran fluida pada temperatur yang tepat untuk proses berikutnyaUntuk mengkondensasikan uapUntuk menguapkan fluidaUntuk memanfaatkan panas buang Untuk pembangkitan daya

  • Feed-effluent exchangerFeed-effluentexchangerExothermic reactionHeat recovery

  • DistillationBottom product

  • Typical crude oil distillationE2E1E3E4E5E6E2E5StorageKeroseneDesalterTop pumparoundTop pumparoundNaphthaand gasesKeroseneReduced crudeLightgas oilHeavygas oilReducedcrudeHeavy gas oilLight gas oilBottom pumparoundDistillation towerBottompumparound

  • Geothermal Power cycleFeedwaterheater

  • Nuclear Power Plant

  • Ocean Thermal Energy Conversion

  • Contoh sebuah APKBundle for shell-and-tube exchanger

  • Heat utilitiesHot utilitiesBoiler generating service steam (maybe a combined heat and power plant)Direct fired heaters (furnace)Electric heatersCold utilitiesCooling tower (wet or dry) providing service cooling waterDirect air-cooled heat exchanger

  • Jenis-Jenis Alat Penukar Kalor

  • KATEGORI UTAMA ALAT PENUKAR KALORKebanyakan Alat Penukar Kalor memeliki 2 aliran fluida, hot dan cold, tetapi beberapa memiliki lebih dari dua aliran fluidaHeat exchangersRecuperatorsRegeneratorsWall separating streamsDirect contact

  • Recuperators dan regeneratorsRecuperativeHas separate flow paths for each fluid which flow simultaneously through the exchanger transferring heat between the streamsRegenerativeHas a single flow path which the hot and cold fluids alternately pass through.Rotating wheel

  • CompactnessCan be measured by the heat-transfer area per unit volume or by channel sizeConventional exchangers (shell and tube) have channel size of 10 to 30 mm giving about 100m2/m3Plate-type exchangers have typically 5mm channel size with more than 200m2/m3More compact types available

  • Compactness

  • Double PipeSimplest type has one tube inside another - inner tube may have longitudinal fins on the outside

    However, most have a number of tubes in the outer tube - can have very many tubes thus becoming a shell-and-tube

  • Shell and TubeAlat Penukar Kalor tipe shell and tube yang biasa digunakan pada industri proses

  • Shell-side flow

  • Baffle

  • Fin Tube

  • Complete shell-and-tube

  • Plate and framePlates hung vertically and clamped in a press or frame.Gaskets direct the streams between alternate plates and prevent external leakagePlates made of stainless steel or higher quality materialPlates corrugated to give points of support and increase heat transfer

  • Plate typesChevronWashboardCorrugations on plateimprove heart transfergive rigidity

    Many points ofcontact and atortuous flow path

  • General view of plate exchangerPlate exchanger normally refers to a gasketted plate- and-frame exchanger

  • Flow Arrangement within a PHEAlternate plates (often same plate types inverted)Gasketsarranged foreach stream toflow betweenalternate plates

  • Air-cooled exchangerAir blown across finned tubes (forced draught type)Can suck air across (induced draught)Finned tubes

  • ACHE bundle

  • Plate-fin exchangerMade up of flat plates (parting sheets) and corrugated sheets which form finsBrazed by heating in vacuum furnace

  • Can have many streams7 or more streams are typical

  • Typical plate-fin

  • Spiral (plate)Good for streams with large solids

  • Cooling TowersLarge shell with packing at the bottom over which water is sprayedCooling by air flow and evaporationAir flow driven by forced or natural convectionNeed to continuously make up the cooling water lost by evaporation

  • Agitated VesselUsed for batch heating or cooling of fluidsAn agitator and baffles promote mixingA range of agitators are usedOften used for batch chemical reaction

  • Printed circuit heat exchangerPlates are etched to give flow channelsStacked to form exchanger blockBlock diffusion welded under high pressure and temperatureBond formed is as strong as the metal itself

  • Printed circuit exchangerNote that compact does notmean small but means largesurface area per unit volume

  • Distribution of typesin terms of market value in Europe

  • Preliminary points on selectionTubes and cylinders can withstand higher pressures than platesIf exchangers can be built with a variety of materials, then it is more likely that you can find a metal which will cope with extreme temperatures or corrosive fluidsMore specialist exchangers have fewer suppliers, longer delivery times and must be repaired by expertsS&Ts cannot normally give high thermal effectiveness, e

  • Design sequenceDesign the process flow flow-sheetSpecify the heat exchanger requirementsSelect the best exchanger type for the jobThermal design of exchangerMechanical design of exchangerLooping back may be necessary at any stage but can be difficult because of the project timetable

  • Who does what?Design the process flow flow-sheetSpecify the heat exchanger requirementsSelect the best exchanger type for the jobThermal design of exchangerMechanical design of exchangerProcessor/end userContractorManufacturer

  • The design of a process heat exchanger usually proceeds through the following steps:

    Process conditions (stream compositions, flow rates, temperatures, pressures) must be specified.Required physical properties over the temperature and pressure ranges of interest must be obtained.The type of heat exchanger to be employed is chosen.A preliminary estimate of the size of the exchanger is made, using a heat-transfer coefficient appropriate to the fluids, the process,and the equipment.A first design is chosen, complete in all details necessary to carry out the design calculations.The design chosen in step 5 is evaluated, or rated, as to its ability to meet the process specifications with respect to both heat transfer and pressure drop.

  • On the basis of the result of step 6, a new configuration is chosen if necessary and step 6 is repeated. If the first design was inadequate to meet the required heat load, it is usually necessary to increase the size of the exchanger while still remaining within specified or feasible limits of pressure drop, tube length, shell diameter, etc. This will sometimes mean going to multiple-exchanger configurations. If the first design more than meets heat-load requirements or does not use all the allowable pressure drop, a less expensive exchanger can usually be designed to fulfill process requirements.

    8. The final design should meet process requirements (within reasonable expectations of error) at lowest cost. The lowest cost should include operation and maintenance costs and credit for ability to meet long-term process changes, as well as installed (capital) cost. Exchangers should not be selected entirely on a lowest-first-cost basis, which frequently results in future penalties.

  • Exchanger specificationHeat load (duty) along with the terminal temperatures of the streamsMaximum pressure drop each streamsliquids - 0.5 bargases/vapours below 2bar - 10% of inlet pressureDesign pressures and temperaturesSize/weight constraintsStandards to applyGeneral standards like ISO, TEMA, ASME, API etcCompanies own standardsOther requirements

  • The designer must supply an exchanger whichMeets the stated specificationHas reasonable initial costs and operating costs (most exchangers are bought on the basis of the cheapest tender)Has a reasonable lifetimeno damaging vibrationno thermal fatigueno unexpected fouling or corrosion