Post on 16-Mar-2019
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Chemical Engineering ThermodynamicsChemical Engineering ThermodynamicsPrepared byPrepared by:: Dr.Dr. NNINIEKINIEK FajarFajar PuspitaPuspita, M.Eng August,, M.Eng August, 20201111Prepared byPrepared by:: Dr. Dr. NNINIEKINIEK FajarFajar PuspitaPuspita, M.Eng August, , M.Eng August, 20201111
2011Gs_V_2011Gs_V_The First Law of The First Law of Thermodynamics_OpenThermodynamics_Open SystemsSystems
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Lesson Lesson 55
Lesson Topics Descriptions
Lesson Lesson 55AA Konservasi Mempresentasikan diskusi NM untuk sistem terbuka.massa Mempertimbangkan hubungan antara kecepatan alir
massa, kecepatan alir volumetrik dan sifat-sifat fluidalokal.
Lesson Lesson 55BB Konservasipanas
Menerapkan hukum I termodinamika (FLT) pada sistemterbuka.Mempertimbangan interaksi kerja yang disebut dengankerja aliran (flow work).
Lesson Lesson 55CC Proses-proses Mempelajari penyederhanaan proses-proses keadaan
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Lesson Lesson 55CC Proses-prosessteady state
Mempelajari penyederhanaan proses proses keadaantunak (steady) dan pengurangan dari persamaan ODE (Ordinary Differential Equation) ke persamaan aljabar.Menyederhanakan FLT untuk alat-alat nozzle, difuser, turbine, kompresor, throtting, mixing dan aliran didalampipa dan didalam saluran pembuluh (duct flow).
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Lesson Lesson 55
Lesson Topics Descriptions
Lesson Lesson 55DD Neraca Mempelajari bagaimana menerapkan prinsip konservasid t i d tid k t kmassa
transienmassa pada proses-proses transien dan tidak tunak(unsteady)
Lesson Lesson 55EE Neracaenergitransien
Mempelajari bagaimana menerapkan FLT pada proses-proses transien dan tidak tunak.
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Open and Closed SystemsIn Chapter 4 we studied closed systems in which nomass crossed the system boundaries.In this chapter we will be considering open systems.For closed systems we considered a control mass.The mass remains constant throughout the processThe mass remains constant throughout the process.Thus
For open systems we consider a control volume.Th d t il i
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The mass does not necessarily remainconstant.Thus, we must keep track of the mass flow rate min, and the mass flow rate mout, of the control volume .
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Mass Balance for Open Systems
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Mass Balances: Systems with Multiple Inlets and Outlets
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Mass Flow Rate and Fluid Velocity
Equations for Determing the Mass Flow Rate
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Summary Chapter 5, Lesson A - The First Law of Thermodynamics - Open Systems
CHAPTER 5, LESSON A - THE FIRST LAW OF THERMODYNAMICS - OPEN SYSTEMS
Memperkenalkan konservasi masa untuk open sistem persamaan NM
Energy Balance on a Closed System
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Energy Balance on an Open System
Enthalpy Form of the 1st Law for Open Systems
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1st Law: Multiple Inlets & Outlets
Summary Chapter 5, Lesson B - Conservation of Mass
CHAPTER 5, LESSON B - CONSERVATION OF MASS
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General Form of the 1st Law for Open Systems1st Law: Enthalpy Form, Muliple Inlets & Outlets
Steady-State Energy Balances
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1st Law, Open Systems, Steady-State
Steady-State Mass Balances
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Single-Input, Single-Output Systems at Steady-State
Steady-State Processes: Building Blocks for Cycles
Nama Proses Tipe Proses Diskripsi Proses Efek atau Hasil
Decrease the cross-Nozzle SISO
Decrease the cross-sectional area for flow in a pipe
Increases velocity and decreases pressure
Diffuser SISO Increase cross-sectional area for flow
Decreases velocity & increases pressure
Turbine SISORotating machine that produces shaft work by reducing the pressure
Decreases pressure, density and usually temperature as wellreducing the pressure temperature as well.
Compressor SISOMachine that uses shaft work to increase the pressure
Increases pressure, density and usually temperature as well
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Steady-State Processes: Building Blocks for Cycles
Nama Proses
Tipe Proses Diskripsi Proses Efek atau Hasil
P Heat transfer between H i l d d Process HeatExchanger
MIMO
Heat transfer between two flowing fluids. Two inlets and two outlets, without mixing.
Hot stream is cooled and the cold stream is warmed
Utility HeatExchanger SISO
Heat exchange with an unspecified utility stream
Temperature increases or decreases
A "tee" in a pipe Two Most properties of the StreamMixer MISO
A tee in a pipe. Two streams enter and mix and leave as a single stream
Most properties of the effluent are the mass-average of the properties of the two feed streams
Pipe orDuct SISO Fluid flow through a
pipeor ductNo terms in the 1st Law cancel
1st Law for Nozzles and Diffusers
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Nozzle and Diffuser Example #1
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1st Law for Turbines and Compressors
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Turbine and Compressor Example #2
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1st Law for Throttling Devices
Throttling Valve Example #3
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Heat Exchangers: Symbols & Strategy
1st Law for HEXs: SISO Applied Twice
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1st Law for Mixing Chambers
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Example Problem with Complete Solution
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1st Law for Pipe & Duct Flow
Summary Chapter 5, Lesson C - Conservation of Energy
CHAPTER 5, LESSON C - CONSERVATION OF ENERGYMenerapkan Hukum I Termodinamika pada proses-proses steady-state dimana variabel variabel roses tidak berubah dengan waktustate, dimana variabel-variabel proses tidak berubah dengan waktu.
Sifat-sifat fisis berbeda dari titik ke titik didalam sistem. Interaksi panas dan kerja diantara sistem dan lingkungannya juga tetap konstan.Pada keadaan steady-state berlaku persamaan aljabar, bukan persamaan diferensial.
Menganalisa alat proses dan menyederhanakan Hukum I Termodinamika berdasarkan pada karakteristik setiap alat.
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Summary Chapter 5, Lesson C - Conservation of Energy
Device Objective
NozzleMenurunkan kecepatan fluida dengan menurunkan tekanan.
DiffuserMenaikkan tekanan fluida dengan menurunkan kecepatannya.
Turbine Kerja dihasilkan dengan menurunkan entalpi.
CompressorKerja merupakan input untuk menaikkan entalpi dan tekanan fluida.
Throttling DevicesMenurunkan tekanan tanpa kerja apapun dan sedikit perpindahan panas.
Heat Exchangers Dua aliran bertukar panas tanpa pencampuran.
Mixing ChambersDua atau lebih aliran umpan bercampur dan membentuk aliran keluar tunggal.
Pipes & DuctsFluida mengalir melalui pipa atau saluran: persamaan Bernoulli.