Vacuum I. G. Franchetti CAS - Bilbao. 30/5/2011 G. Franchetti 1
|
|
- Eugenia Dawson
- 5 years ago
- Views:
Transcription
1 Vacuum I G. Franchetti CAS - Bilbao 30/5/2011 G. Franchetti 1
2 Index Introduction to Vacuum Vacuum and the Beam Flow Regimes Creating Vacuum 30/5/2011 G. Franchetti 2
3 Vacuum in accelerators All beam dynamics has the purpose of controlling a charged beam particle Structure of magnets and RF structure have the purpose of creating a proper guiding (E,B) structure However in an accelerator are present a jungle of unwanted particles which creates a damaging background for beam operation 30/5/2011 G. Franchetti 3
4 Characteristic of Vacuum Vacuum is considered as a Gas which is characterized by Macroscopic Quantities Pressure Temperature Density Composition Aim: Minimize the interaction of beam with vacuum gas Microscopic Quantities Kinetic Theory 30/5/2011 G. Franchetti 4
5 Typical numbers Particles m -3 Atmosphere 2.5 x Vacuum Cleaner 2 x Freeze dryer Light bulb Thermos flask TV Tube Low earth orbit (300km) H 2 in LHC ~10 14 SRS/Diamond Surface of Moon Interstellar space 10 5 R.J. Reid 30/5/2011 G. Franchetti 5
6 Particle Wall collision m The velocity after wall collision depends on the particle-wall interaction v 2 interaction v 1 Momentum is propagated to the wall 30/5/2011 G. Franchetti 6
7 Pressure SI Units: Low vacuum Atm. pressure to 1 mbar m Medium vacuum High Vacuum (HV) Ultrahigh vacuum (UHV) Extreme high vacuum (XHV) 1 to 10-3 mbar 10-3 to 10-8 mbar 10-8 to mbar less than mbar other units: 30/5/2011 G. Franchetti 7
8 Particle Particle interaction v 1 v 1 In a gas large number of collisions Most likely process P-P collision v 2 Interaction m v 2 For elastic collisions: 1) Energy conservation 2) Momentum conservation Temperature 30/5/2011 G. Franchetti 8
9 Typical numbers Air at T= 20 o C 20% O 2 M O = 8x2 g-mole = 8x2/N A = 2.65 x g 80% N 2 M N = 7x2 g-mole = 7x2/N A = 2.32 x g Therefore Molecules run fast! But the average velocity is 30/5/2011 G. Franchetti 9
10 f Velocity Distribution When a gas is at equilibrium the distribution of the velocity follows the Maxwell-Boltzmann distribution max velocity ave. velocity /5/2011 G. Franchetti v/v a
11 Equation of state An ideal gas in a container of volume V satisfies the equation of state For a gas in equilibrium SI units P Pressure [Pa] V Volume in [m 3 ] n moles [1] T absolute temperature [K] R 0 = [Nm/(mole K)] universal constant of gas k B = 1.38x10-23 [JK -1 ] Boltzmann constant N A = 6.022x10 23 [1] Avogadro s Number 30/5/2011 G. Franchetti 11
12 Mean free path free path = path of a particle between two collisions 30/5/2011 G. Franchetti 12
13 Mean free path v Effective area covered by the rest atoms Density of atoms Cross-section Transverse area v # particles at l + Δl that did not collide N(l) = particle at l Particles that did not collide 30/5/2011 G. Franchetti 13
14 Mean free path How many particles collide between and? Therefore dn particles travelled a distance l and then collided Probability that a particle travel l and then collide is Mean free path In a gas 30/5/2011 G. Franchetti 14
15 Example Air at T = 20 0 C and P = 1 atm From equation of state atom/m 3 Diameter of molecule of air Mean free path 30/5/2011 G. Franchetti 15
16 N 2 at T = 20 0 C, d = m 30/5/2011 G. Franchetti 16
17 Vacuum and Beam 30/5/2011 G. Franchetti 17
18 Beam lifetime After a beam particle collides with a gas atom, it gets ionized and lost because of the wrong charge state with respect to the machine s optics Beam of particles going through a vacuum gas survives according to As beam particle have a velocity v 0, then From the equation of state Beam lifetime Beam lifetime sets the vacuum constrain 30/5/2011 G. Franchetti 18
19 Example It is important to know the cross-section of the interaction beam-vacuum Example LHC Of what is formed the vacuum? Does it depends on the energy? H 2 at 7 TeV at T = 5 0 K for Nuclear scattering cross section at 7 TeV for different gases and the corresponding densities and equivalent pressures for a 100 hours beam lifetime LHC Design Report 30/5/2011 G. Franchetti 19
20 O. Gröbner, CAS /5/2011 G. Franchetti 20
21 Impingement rate For a Maxwell-Boltzmann distribution J units: [#/( s m 2 )] and 30/5/2011 G. Franchetti 21
22 More on collision mean free path mean free path 30/5/2011 G. Franchetti 22
23 Knudsen Number Flow Regimes Continuous Regime Particles collide mainly among them the fluid is continuous SI units: [1] Transitional Regime This is a regime in between continuous and molecular Molecular Regime particles collide mainly with walls 30/5/2011 G. Franchetti 23
24 The Throughput Vessel with a gas at Number of particles The quantity is proportional to the number of particles is called throughput SI units: [Pa m 3 /s] 30/5/2011 G. Franchetti 24
25 Conductance In absence of adsorption and desorption processes the throughput does not change 1 T = constant 2 equal Conductance SI units: [m 3 /s] 30/5/2011 G. Franchetti 25
26 Composition (Series) C 1 C 2 P u1 P d1 =P u2 P d2 equal throughput T = constant Conductance of /5/2011 G. Franchetti 26
27 Composition (Parallel) C 1 Vessel 1 Vessel 2 Conductance of 1+2 P u P d C 2 T = constant 30/5/2011 G. Franchetti 27
28 Molecular Flow Regime dominated by Particle Wall interaction K n > 0.5 P < 1.3 x 10-3 mbar D = 0.1 m Classical Molecular Mechanics regime m v 2 v 2??? v 1 v 1 30/5/2011 G. Franchetti 28
29 Cosine-Law 1. A particle after a collision with wall will loose the memory of the initial direction 2. After a collision a particle has the same velocity v 3. The probability that particles emerge in a certain direction follow the cosine law = solid angle 30/5/2011 G. Franchetti 29
30 Consequences Concept of Transmission probability 1 A gas particle can return back! 2 In the molecular regime two fluxes in opposite direction coexist particle flux = N 1 = particle per second through 1 N 2 = particle per second through 2 30/5/2011 G. Franchetti 30
31 Conductance of an Aperture Gas current Volumetric flow Downstream Upstream Throughput Conductance 30/5/2011 G. Franchetti 31
32 Conductance of a long tube long tube = no end effect d stationary state L 0 make α which is wrong: This result is valid for L long The dependence of 1/L is consistent with the rule of composition of conductance 30/5/2011 G. Franchetti 32
33 Continuum flow regime K n < 0.01 P > 6.5 x 10-2 mbar V = 0.1 m Roughly more than 100 collision among particles before wall collision Local perturbation of propagate through a continuum medium Collision among particles create the Viscosity Collision with walls cancel the velocity zero velocity at the walls Max. velocity 30/5/2011 G. Franchetti 33
34 Viscous/Laminar regime Reynold Number Laminar Regime ρ = density of gas [Kg/m 3 ] v = average velocity [m/s] D h = hydraulic diameter [m] Turbulent Regime A = cross sectional area B = perimeter η = fluid viscosity [Pa-s] M. Lesiuer, Turbulence in Fluids, 4 th Edition, Ed. Springer 30/5/2011 G. Franchetti 34
35 Reynold Number as function of Throughput For air (N 2 ) at T=20C η = 1.75 x 10-5 Pa-s with Therefore the transition to a turbulent flow takes place at the throughput of For a pipe of d = 25 mm [mbar l /s] [mm] At P = 1 atm this threshold corresponds to v = m/s 30/5/2011 G. Franchetti 35
36 Laminar Regime 1. Fluid is incompressible: true also for gas when Ma < Fluid is fully developed 3. Motion is laminar Re < Velocity at Walls is zero Fully developed flow entry length velocity distribution at injection in the pipe velocity distribution of a fully developed flow 30/5/2011 G. Franchetti 36
37 Conductance in Laminar Regime long tube = no end effect D P u P d L Conductance: where The conductance now depends on the pressure! 30/5/2011 G. Franchetti 37
38 Conductance in Turbulent Regime long tube = no end effect D P u P d L The throughput becomes a complicated relation (derived from the Darcy-Weisbach formula) Darcy friction factor, dependent from the Reynold number 30/5/2011 G. Franchetti 38
39 Sources of vacuum degradation 30/5/2011 G. Franchetti 39
40 P [atm] Evaporation/Condensation At equilibrium P E = saturate vapor pressure condensation Example: water vapor pressure 1 evaporation T [C] 30/5/2011 G. Franchetti 40
41 Outgassing The outgassing is the passage of gas from the wall of the Vessel or Pipe to the vacuum Mean stay time Θ = fraction of sites occupied E d [Kcal/mole] Cases τ d [s] 0.1 Helium 1.18 x H 2 physisorption 1.3 x Ar,CO,N 2,CO 2 physisorption 1.6 x Weak chemisorption 2.6 x 10-6 Throughput due to outgassing 20 H 2 chemisorption x 10 5 (~half week) 30 CO/Ni chemisorption 1.6 x 10 9 (~50 years) x (~half age of earth) N s = A x 3x10 15 A = surface in cm O.W chemisorption 1.35 x (larger than the age of universe) P. Chiggiato, CAS /5/2011 G. Franchetti 41
42 Leaks High vacuum system Q L < 10-6 mbar l /s Q L < 10-5 mbar l /s Q L < 10-4 mbar l /s very tight tight leaks Small Channels Diameter hole 0.01 mm m Leaks rate 10-2 mbar-l/s mbar-l/s K. Zapfe, CAS years for leakage of 1 cm 3 30/5/2011 G. Franchetti 42
43 Pumps and Gas flow Ideal Pump particles that enter in this chamber never returns back!! Pumping speed S 0 [m 3 /s] but S 0 is Here Example N 2 at T=20C Take D=0.1m S 0 = 0.92 m 3 /s 30/5/2011 G. Franchetti 43
44 Pumps and Conductance Pumping speed S [m 3 /s] Pumping speed of ideal pump S 0 d conductance C As the throughput is preserved Example: if the pipe is long l=100d m 3 /s 30/5/2011 G. Franchetti 44
45 Pumping Process -- Pump-down Time - - Ultimate Pressure hole Pump throughput due to evaporation throughput due to outgassing throughput due to leaks effective throughput 30/5/2011 G. Franchetti 45
46 Pumping Process -- Pump-down Time - - Ultimate Pressure Therefore P/P 0 1 Ultimate pressure equilibrium between sources of throughput and pumps throughput t [s] Pump down time 30/5/2011 G. Franchetti 46
47 Multistage pumps First stage pump down Second stage P/P 0 1 t [s] 30/5/2011 G. Franchetti 47
48 Creating the Vacuum: Pumps Examples of vacuum in some accelerators LHC mbar (LHC Design Report) FAIR HEBT 10-9 mbar J.Y. Tang ICA01, TUAP062 SIS mbar A. Kraemer EPAC2006, TUPCH175 30/5/2011 G. Franchetti 48
49 Positive Displacement Pumps Principle: A volume of gas is displaced out of the Vessel Vessel Out Piston Pumps volume V P out Rotary Pumps Liquid ring pumps P in Dry vacuum pump A compression of the volume V is always necessary to bring the pressure from P in to a value larger then P out 30/5/2011 G. Franchetti 49
50 Piston Pumps Vessel P i P o P o Minimum volume Vmin 30/5/2011 G. Franchetti 50
51 Piston Pumps Vessel P i P o P Here the pressure P is smaller than P o but larger than P i 30/5/2011 G. Franchetti 51
52 Piston Pumps Vessel P i P o P i At this point the internal pressure becomes equal to P i P i V i = P 0 V min 30/5/2011 G. Franchetti 52
53 Piston Pumps Vessel P i P o The internal pressure remains P i but the volume increase to V max Effective gas volume entered into the pump equal to V max V i : this is the gas which will be expelled 30/5/2011 G. Franchetti 53
54 Piston Pumps Vessel P i P o P o At the Volume V c the internal pressure becomes equal to P o and the valve opens. P o V c = P i V max and from now on the gas entered into the pump goes out 30/5/2011 G. Franchetti 54
55 Piston Pumps Therefore if the pumps make N c cycles per second Conclusion: the pumping speed depends on the ratio of outlet/inlet pressure When the inlet pressure is too low the pump stops pumping S S 0 P limit P o 30/5/2011 G. Franchetti 55
56 If the gas compression/expansion is isentropic then all transformation follow the law hence Clearly the dependence affects the ultimate pressure even in absence of sources of throughput Ultimate pressure 30/5/2011 G. Franchetti 56
57 General Pump Pumping speed of ideal pump S 0 But in real pumps there is a backflow Pump Inlet Outlet P i P 0 Pump throughput Backflow 30/5/2011 G. Franchetti 57
58 Zero Load Compression Rate Inlet P i0 P 0 Outlet Zero Load compression rate Closed Backflow The backflow is found 30/5/2011 G. Franchetti 58
59 Rotary Pumps S = m 3 /h Pl = 5 x 10-2 mbar (1stage) Pl = 10-3 mbar (2stage) Gas displaced in the moving vane Gas Ballast During the compression there can be gas component (G), which partial pressure P G can be too high condensation But the maximum pressure during compression do not exceed P 0 therefore by injectionng non condensable gas during the compression rate P G is lowered blow the condensation point 30/5/2011 G. Franchetti 59
60 Liquid Ring Pumps S = m 3 /h P = 1000 mbar 33 mbar The gas enter in the cavity which expand. When the pressure in the cavity reaches the sature vapor pressure P s the water boils. During the compression the vapor bubbles implode creating the CAVITATION At T = 15 0 C P s = 33 mbar which sets the P limit =Ps 30/5/2011 G. Franchetti 60
61 Dry Vacuum Pumps: Roots pumping speed: m 3 /h operating pressure: mbar 30/5/2011 G. Franchetti 61
62 Kinetic Vacuum Pumps Principle The pump gives a momentum to the gas particles so that they flows out from the outlet Molecular drag pump Turbo molecular Pump Diffusion Ejector pump 30/5/2011 G. Franchetti 62
63 Molecular Drag Pumps Based on the molecular drag effect m U 30/5/2011 G. Franchetti 63
64 w h U Volumetric flow: Taking into account of the backflow K 0 = zero load compression rate, 30/5/2011 G. Franchetti 64
65 P i P o U The zero load compression rate is But for a long tube if U ~ v a Example L = 250 mm, h = 3 mm S 0 /C > 10 and K 0 >> 1 A. Chambers, Modern Vacuum Physics, CRC, /5/2011 G. Franchetti 65
66 Example of Molecular drag pump pumping speed: l/s operating pressure: Pa ultimate pressure 10-5 to 10-3 Pa 30/5/2011 G. Franchetti 66
67 Turbo-molecular pump Principle v a φ U General particle velocity distribution U tilted blades 30/5/2011 G. Franchetti 67
68 Turbo-molecular pump In the reference frame of the rotating blades U v a - U φ General particle velocity distribution tilted blades 30/5/2011 G. Franchetti 68
69 Turbo-molecular pump In the reference frame of the rotating blades U v a - U General particle velocity distribution 30/5/2011 G. Franchetti 69
70 Turbo-molecular pump Returning in the laboratory frame U U The vacuum particle has received a momentum that pushes it down but the component of velocity tangential becomes too large 30/5/2011 G. Franchetti 70
71 Multistage U U rotor stator U U rotor stator The rotational component is lost and another stage can be placed 30/5/2011 G. Franchetti 71
72 Turbo-molecular pump Probability of pumping The maximum probability W max is found when P i = P o And we also find that K 0 = compression rate at zero load 30/5/2011 G. Franchetti 72
73 The compression rate at zero load Therefore therefore different species have different pumping probability In addition the maximum pumping probability W max is Therefore we find that the maximum pumping speed independent on the gas mass is 30/5/2011 G. Franchetti 73
74 Maximum compression as function of foreline pressure Pumping speed as function of the inlet pressure (Blazers Pfeiffer) pumping speed: l/s ultimate pressure 10-8 to 10-7 Pa (Blazers Pfeiffer) 30/5/2011 G. Franchetti 74
75 End of Vacuum I 30/5/2011 G. Franchetti 75
( KS A ) (1) , vapour, vapor (USA) , saturation vapour pressure. , standard reference conditions for gases. , degree of saturation
( KS A 3014-91 ) (1), standard reference conditions for gases 0, 101325 Pa (1 =760mmHg ), vacuum, low ( rough ) vacuum 100Pa, medium vacuum 100 01 Pa, high vacuum 01 10 5 Pa, ultra high vacuum ( UHV )
dmγ v dt = q E +q v B, (1)
Vacuum I Giuliano Franchetti GSI Darmstadt, D-64291 Darmstadt, Germany Abstract This paper is an introduction to the basics of vacuum. It is intended for readers unfamiliar with the topic; more advanced
VACUUM PUMPING METHODS
VACUUM PUMPING METHODS VACUUM PUMPS (METHODS) Positive Displacement Vacuum Gas Transfer Vacuum Kinetic Vacuum Entrapment Vacuum Adsorption Reciprocating Displacement Rotary Drag Fluid Entrainment Ion Transfer
K n. III. Gas flow. 1. The nature of the gas : Knudsen s number. 2. Relative flow : Reynold s number R = ( dimensionless )
III. Gas flow. The nature of the gas : Knudsen s number K n λ d 2. Relative flow : U ρ d η U : stream velocity ρ : mass density Reynold s number R ( dimensionless ) 3. Flow regions - turbulent : R > 2200
Lecture 3 Vacuum Science and Technology
Lecture 3 Vacuum Science and Technology Chapter 3 - Wolf and Tauber 1/56 Announcements Homework will be online from noon today. This is homework 1 of 4. 25 available marks (distributed as shown). This
UHV - Technology. Oswald Gröbner
School on Synchrotron Radiation UHV - Technology Trieste, 20-21 April 2004 1) Introduction and some basics 2) Building blocks of a vacuum system 3) How to get clean ultra high vacuum 4) Desorption phenomena
Lecture 4. Ultrahigh Vacuum Science and Technology
Lecture 4 Ultrahigh Vacuum Science and Technology Why do we need UHV? 1 Atmosphere = 760 torr; 1 torr = 133 Pa; N ~ 2.5 10 19 molecules/cm 3 Hertz-Knudsen equation p ZW 1/ 2 ( 2mk T) At p = 10-6 Torr it
Physical Vapor Deposition
Physical Vapor Deposition EVAPORATION SPUTTERING Typically used for metallization of semiconductors. Both Evaporation & Sputtering are done in vacuum environments. Typically: y Evaporation Pressures are
Conductance of an aperture
n Vacuum φ A 4 How many molecules travel through A in a time t? P P A onductance of an aperture 3 q φa 3.64 0 ( T / M) na Volume of gas passing through A? Q Q Q / ΔP 3.64 ( T / M ) 3 dv/dt q/n 3.64 0 (
Conductance of an aperture
n Vacuum φ 4 How many molecules travel through in a time t? P P onductance of an aperture q φ.64 0 ( T / M) n Volume of gas passing through? Q Q dv/dt q/n.64 0 ( T / M) Q P Q / ΔP.64 (T / M ) l/s.64 0
Vacuum Pumps. Two general classes exist: Gas transfer physical removal of matter. Mechanical, diffusion, turbomolecular
Vacuum Technology Vacuum Pumps Two general classes exist: Gas transfer physical removal of matter Mechanical, diffusion, turbomolecular Adsorption entrapment of matter Cryo, sublimation, ion Mechanical
9. Pumps (compressors & turbines) Partly based on Chapter 10 of the De Nevers textbook.
Lecture Notes CHE 31 Fluid Mechanics (Fall 010) 9. Pumps (compressors & turbines) Partly based on Chapter 10 of the De Nevers textbook. Basics (pressure head, efficiency, working point, stability) Pumps
Vacuum Science and Technology in Accelerators
Vacuum Science and Technology in Accelerators Ron Reid Consultant ASTeC Vacuum Science Group (ron.reid@stfc.ac.uk) Lecture 1: 1 of 25 Aims To give a basic understanding of vacuum Underlying physical principles
A drop forms when liquid is forced out of a small tube. The shape of the drop is determined by a balance of pressure, gravity, and surface tension
A drop forms when liquid is forced out of a small tube. The shape of the drop is determined by a balance of pressure, gravity, and surface tension forces. 2 Objectives 3 i i 2 1 INTRODUCTION Property:
Lecture Outline Chapter 17. Physics, 4 th Edition James S. Walker. Copyright 2010 Pearson Education, Inc.
Lecture Outline Chapter 17 Physics, 4 th Edition James S. Walker Chapter 17 Phases and Phase Changes Ideal Gases Kinetic Theory Units of Chapter 17 Solids and Elastic Deformation Phase Equilibrium and
Vacuum techniques (down to 1 K)
Vacuum techniques (down to 1 K) For isolation (deep Knudsen regime) liquid helium dewar / inner vacuum jacket Leak testing at level 10-11 Pa m3/s (10-10 mbar l/s) liquid helium dewar & transfer syphon
To move a particle in a (straight) line over a large distance
2.1 Introduction to Vacuum Technology 2.1.1 Importance of Vacuum Technology for Processing and Characterization Under partial vacuum conditions (pressures orders of magnitude below ambient atmospheric
Form I. Midterm II. March 30, 1999
Name: Midterm II March 30, 1999 Useful constants: ρ water =1000 kg/m 3, G=6.67x10-11 Nm 2 /kg 2, N A =6.02x10 23, R=8.31 J/(mol K), k = 1.38x10-23 J/K, D isk = 1/2 MR 2, M e =5.98x10 24 kg, g=9.8 m/s 2.
Review of Fluid Mechanics
Chapter 3 Review of Fluid Mechanics 3.1 Units and Basic Definitions Newton s Second law forms the basis of all units of measurement. For a particle of mass m subjected to a resultant force F the law may
Lecture 10. Vacuum Technology and Plasmas Reading: Chapter 10. ECE Dr. Alan Doolittle
Lecture 10 Vacuum Technology and Plasmas Reading: Chapter 10 Vacuum Science and Plasmas In order to understand deposition techniques such as evaporation, sputtering,, plasma processing, chemical vapor
CHAPTER EIGHT P U M P I N G O F L I Q U I D S
CHAPTER EIGHT P U M P I N G O F L I Q U I D S Pupmps are devices for supplying energy or head to a flowing liquid in order to overcome head losses due to friction and also if necessary, to raise liquid
Progress Report on Chamber Dynamics and Clearing
Progress Report on Chamber Dynamics and Clearing Farrokh Najmabadi, Rene Raffray, Mark S. Tillack, John Pulsifer, Zoran Dragovlovic (UCSD) Ahmed Hassanein (ANL) Laser-IFE Program Workshop May31-June 1,
M E 320 Professor John M. Cimbala Lecture 23
M E 320 Professor John M. Cimbala Lecture 23 Today, we will: Discuss diffusers and do an example problem Begin discussing pumps, and how they are analyzed in pipe flow systems D. Diffusers 1. Introduction.
Nicholas J. Giordano. Chapter 10 Fluids
Nicholas J. Giordano www.cengage.com/physics/giordano Chapter 10 Fluids Fluids A fluid may be either a liquid or a gas Some characteristics of a fluid Flows from one place to another Shape varies according
Vacuum. Residual pressure can thwart the best cryogenic design. Each gas molecule collision carries ~kt from the hot exterior to the cold interior.
Vacuum Residual pressure can thwart the best cryogenic design Each gas molecule collision carries ~kt from the hot exterior to the cold interior. 1 millitorr = 3.5x10¹³/cm³ Gas atoms leaving the hot surfaces
Vacuum for Accelerators
Vacuum for Accelerators Oswald Gröbner Baden, 22 September 2004 1) Introduction and some basics 2) Pumps used in accelerators 3) Desorption phenomena 4) Practical examples Oswald Gröbner, Retired from
Repetition: Physical Deposition Processes
Repetition: Physical Deposition Processes PVD (Physical Vapour Deposition) Evaporation Sputtering Diode-system Triode-system Magnetron-system ("balanced/unbalanced") Ion beam-system Ionplating DC-glow-discharge
Introduction to Turbomachinery
1. Coordinate System Introduction to Turbomachinery Since there are stationary and rotating blades in turbomachines, they tend to form a cylindrical form, represented in three directions; 1. Axial 2. Radial
An Essential Requirement in CV Based Industrial Appliances.
Measurement of Flow P M V Subbarao Professor Mechanical Engineering Department An Essential Requirement in CV Based Industrial Appliances. Mathematics of Flow Rate The Scalar Product of two vectors, namely
LEAKLESS COOLING SYSTEM V.2 PRESSURE DROP CALCULATIONS AND ASSUMPTIONS
CH-1211 Geneva 23 Switzerland EDMS No. ST/CV - Cooling of Electronics & Detectors GUIDE LEAKLESS COOLING SYSTEM V.2 PRESSURE DROP CALCULATIONS AND ASSUMPTIONS Objectives Guide to Leakless Cooling System
Rough (low) vacuum : Medium vacuum : High vacuum (HV) : Ultrahigh vacuum (UHV) :
4. UHV & Effects of Gas Pressure 4.1 What is Ultra-high Vacuum (UHV)? 4.2 Why is UHV required for Surface Studies? 4.3 Exercises - Effects of Gas Pressure Vacuum technology has advanced considerably over
vector H. If O is the point about which moments are desired, the angular moment about O is given:
The angular momentum A control volume analysis can be applied to the angular momentum, by letting B equal to angularmomentum vector H. If O is the point about which moments are desired, the angular moment
Name Date Class THE NATURE OF GASES
13.1 THE NATURE OF GASES Section Review Objectives Describe the assumptions of the kinetic theory as it applies to gases Interpret gas pressure in terms of kinetic theory Define the relationship between
Vacuum II. G. Franchetti CAS - Bilbao. 30/5/2011 G. Franchetti 1
Vacuum II G. Franchetti CAS Bilbao 30/5/2011 G. Franchetti 1 Index Creating Vacuum (continuation) Measuring Vacuum Partial Pressure Measurements 30/5/2011 G. Franchetti 2 Laminar flow Cold surface Diffusion
Lesson 6 Review of fundamentals: Fluid flow
Lesson 6 Review of fundamentals: Fluid flow The specific objective of this lesson is to conduct a brief review of the fundamentals of fluid flow and present: A general equation for conservation of mass
MECHANICAL PROPERTIES OF FLUIDS:
Important Definitions: MECHANICAL PROPERTIES OF FLUIDS: Fluid: A substance that can flow is called Fluid Both liquids and gases are fluids Pressure: The normal force acting per unit area of a surface is
Lecturer, Department t of Mechanical Engineering, SVMIT, Bharuch
Fluid Mechanics By Ashish J. Modi Lecturer, Department t of Mechanical Engineering, i SVMIT, Bharuch Review of fundamentals Properties of Fluids Introduction Any characteristic of a system is called a
MECA-H-402: Turbomachinery course Axial compressors
MECA-H-40: Turbomachinery course Axial compressors Pr. Patrick Hendrick Aero-Thermo-Mecanics Year 013-014 Contents List of figures iii 1 Axial compressors 1 1.1 Introduction...............................
FE Exam Fluids Review October 23, Important Concepts
FE Exam Fluids Review October 3, 013 mportant Concepts Density, specific volume, specific weight, specific gravity (Water 1000 kg/m^3, Air 1. kg/m^3) Meaning & Symbols? Stress, Pressure, Viscosity; Meaning
Introduction to Fluid Machines, and Compressible Flow Prof. S. K. Som Department of Mechanical Engineering Indian Institute of Technology, Kharagpur
Introduction to Fluid Machines, and Compressible Flow Prof. S. K. Som Department of Mechanical Engineering Indian Institute of Technology, Kharagpur Lecture - 09 Introduction to Reaction Type of Hydraulic
Chapter 14. Lecture 1 Fluid Mechanics. Dr. Armen Kocharian
Chapter 14 Lecture 1 Fluid Mechanics Dr. Armen Kocharian States of Matter Solid Has a definite volume and shape Liquid Has a definite volume but not a definite shape Gas unconfined Has neither a definite
EXPERIMENT No.1 FLOW MEASUREMENT BY ORIFICEMETER
EXPERIMENT No.1 FLOW MEASUREMENT BY ORIFICEMETER 1.1 AIM: To determine the co-efficient of discharge of the orifice meter 1.2 EQUIPMENTS REQUIRED: Orifice meter test rig, Stopwatch 1.3 PREPARATION 1.3.1
FE Fluids Review March 23, 2012 Steve Burian (Civil & Environmental Engineering)
Topic: Fluid Properties 1. If 6 m 3 of oil weighs 47 kn, calculate its specific weight, density, and specific gravity. 2. 10.0 L of an incompressible liquid exert a force of 20 N at the earth s surface.
Active Control of Separated Cascade Flow
Chapter 5 Active Control of Separated Cascade Flow In this chapter, the possibility of active control using a synthetic jet applied to an unconventional axial stator-rotor arrangement is investigated.
17-1 Ideal Gases. Gases are the easiest state of matter to describe - All ideal gases exhibit similar behavior.
17-1 Ideal Gases Gases are the easiest state of matter to describe - All ideal gases exhibit similar behavior. An ideal gas is one that is thin enough, that the interactions between molecules can be ignored.
Experiment- To determine the coefficient of impact for vanes. Experiment To determine the coefficient of discharge of an orifice meter.
SUBJECT: FLUID MECHANICS VIVA QUESTIONS (M.E 4 th SEM) Experiment- To determine the coefficient of impact for vanes. Q1. Explain impulse momentum principal. Ans1. Momentum equation is based on Newton s
Chapter 10. Thermal Physics. Thermodynamic Quantities: Volume V and Mass Density ρ Pressure P Temperature T: Zeroth Law of Thermodynamics
Chapter 10 Thermal Physics Thermodynamic Quantities: Volume V and Mass Density ρ Pressure P Temperature T: Zeroth Law of Thermodynamics Temperature Scales Thermal Expansion of Solids and Liquids Ideal
Classify each of these statements as always true, AT; sometimes true, ST; or never true, NT.
Chapter 11 THE NATURE OF GASES States of Matter Describe the motion of gas particles according to the kinetic theory Interpret gas pressure in terms of kinetic theory Key Terms: 1. kinetic energy 2. gas
Physics 207 Lecture 18
Physics 07, Lecture 8, Nov. 6 MidTerm Mean 58.4 (64.6) Median 58 St. Dev. 6 (9) High 94 Low 9 Nominal curve: (conservative) 80-00 A 6-79 B or A/B 34-6 C or B/C 9-33 marginal 9-8 D Physics 07: Lecture 8,
Previous Lecture. Electron beam lithoghraphy e - Electrons are generated in vacuum. Electron beams propagate in vacuum
Previous Lecture Electron beam lithoghraphy e - Electrons are generated in vacuum Electron beams propagate in vacuum Lecture 6: Vacuum & plasmas Objectives From this vacuum lecture you will learn: What
PHYSICAL VAPOR DEPOSITION OF THIN FILMS
PHYSICAL VAPOR DEPOSITION OF THIN FILMS JOHN E. MAHAN Colorado State University A Wiley-Interscience Publication JOHN WILEY & SONS, INC. New York Chichester Weinheim Brisbane Singapore Toronto CONTENTS
C ONTENTS CHAPTER TWO HEAT CONDUCTION EQUATION 61 CHAPTER ONE BASICS OF HEAT TRANSFER 1 CHAPTER THREE STEADY HEAT CONDUCTION 127
C ONTENTS Preface xviii Nomenclature xxvi CHAPTER ONE BASICS OF HEAT TRANSFER 1 1-1 Thermodynamics and Heat Transfer 2 Application Areas of Heat Transfer 3 Historical Background 3 1-2 Engineering Heat
Chapter 5 Control Volume Approach and Continuity Equation
Chapter 5 Control Volume Approach and Continuity Equation Lagrangian and Eulerian Approach To evaluate the pressure and velocities at arbitrary locations in a flow field. The flow into a sudden contraction,
11.1 Mass Density. Fluids are materials that can flow, and they include both gases and liquids. The mass density of a liquid or gas is an
Chapter 11 Fluids 11.1 Mass Density Fluids are materials that can flow, and they include both gases and liquids. The mass density of a liquid or gas is an important factor that determines its behavior
Diffusion and Adsorption in porous media. Ali Ahmadpour Chemical Eng. Dept. Ferdowsi University of Mashhad
Diffusion and Adsorption in porous media Ali Ahmadpour Chemical Eng. Dept. Ferdowsi University of Mashhad Contents Introduction Devices used to Measure Diffusion in Porous Solids Modes of transport in
Physics 1501 Lecture 35
Physics 1501: Lecture 35 Todays Agenda Announcements Homework #11 (Dec. 2) and #12 (Dec. 9): 2 lowest dropped Honors students: see me after the class! Todays topics Chap.16: Temperature and Heat» Latent
William В. Brower, Jr. A PRIMER IN FLUID MECHANICS. Dynamics of Flows in One Space Dimension. CRC Press Boca Raton London New York Washington, D.C.
William В. Brower, Jr. A PRIMER IN FLUID MECHANICS Dynamics of Flows in One Space Dimension CRC Press Boca Raton London New York Washington, D.C. Table of Contents Chapter 1 Fluid Properties Kinetic Theory
Midterm II Solutions
Name: Midterm II Solutions March 30, 1999 Correct Responses are given in bold type Useful constants: ρ water =1000 kg/m 3, G=6.67x10-11 Nm 2 /kg 2, N A =6.02x10 23, R=8.31 J/(mol K), k = 1.38x10-23 J/K,
Liquids. properties & structure
Liquids properties & structure Energetics of Vaporization when the high energy molecules are lost from the liquid, it lowers the average kinetic energy if energy is not drawn back into the liquid, its
Thermodynamics. Atoms are in constant motion, which increases with temperature.
Thermodynamics SOME DEFINITIONS: THERMO related to heat DYNAMICS the study of motion SYSTEM an object or set of objects ENVIRONMENT the rest of the universe MICROSCOPIC at an atomic or molecular level
KINETIC THEORY. was the original mean square velocity of the gas. (d) will be different on the top wall and bottom wall of the vessel.
Chapter Thirteen KINETIC THEORY MCQ I 13.1 A cubic vessel (with faces horizontal + vertical) contains an ideal gas at NTP. The vessel is being carried by a rocket which is moving at a speed of 500m s 1
Chapter Four Hydraulic Machines
Contents 1- Introduction. 2- Pumps. Chapter Four Hydraulic Machines (لفرع الميكانيك العام فقط ( Turbines. -3 4- Cavitation in hydraulic machines. 5- Examples. 6- Problems; sheet No. 4 (Pumps) 7- Problems;
Optimization of the SIS100 Lattice and a Dedicated Collimation System for Ionisation Losses
Optimization of the SIS100 Lattice and a Dedicated Collimation System for Ionisation Losses P. Spiller, K. Blasche, B. Franczak, J. Stadlmann, and C. Omet GSI Darmstadt, D-64291 Darmstadt, Germany Abstract:
Introduction to Fluid Machines and Compressible Flow Prof. S. K. Som Department of Mechanical Engineering Indian Institute of Technology, Kharagpur
Introduction to Fluid Machines and Compressible Flow Prof. S. K. Som Department of Mechanical Engineering Indian Institute of Technology, Kharagpur Lecture - 21 Centrifugal Compressor Part I Good morning
FLOW IN PIPES. Mark J McCready University of Notre Dame July 24, chemeprof.com
FLOW IN PIPES Mark J McCready University of Notre Dame July 24, 2017 OVERVIEW This lecture will provide the simplest framework to explain The three forces at that are important to fluid flow in pipes The
Chapter 14. Fluid Mechanics
Chapter 14 Fluid Mechanics States of Matter Solid Has a definite volume and shape Liquid Has a definite volume but not a definite shape Gas unconfined Has neither a definite volume nor shape All of these
Petroleum Engineering Dept. Fluid Mechanics Second Stage Dr. Ahmed K. Alshara
Continents Chapter 1. Fluid Mechanics -Properties of fluids -Density, specific gravity, specific volume and Viscosity -Newtonian and non Newtonian fluids -Surface tension Compressibility -Pressure -Cavitations
first law of ThermodyNamics
first law of ThermodyNamics First law of thermodynamics - Principle of conservation of energy - Energy can be neither created nor destroyed Basic statement When any closed system is taken through a cycle,
2 Internal Fluid Flow
Internal Fluid Flow.1 Definitions Fluid Dynamics The study of fluids in motion. Static Pressure The pressure at a given point exerted by the static head of the fluid present directly above that point.
Chapter 13 - States of Matter. Section 13.1 The nature of Gases
Chapter 13 - States of Matter Section 13.1 The nature of Gases Kinetic energy and gases Kinetic energy: the energy an object has because of its motion Kinetic theory: all matter is made if particles in
Differential Mobility Particle Sizer (Aerosol measurements)
Institute for Atmospheric and Climate Science - IACETH Atmospheric Physics Lab Work Differential Mobility Particle Sizer (Aerosol measurements) Abstract A differential mobility particle sizer (DMPS) is
Applied Fluid Mechanics
Applied Fluid Mechanics 1. The Nature of Fluid and the Study of Fluid Mechanics 2. Viscosity of Fluid 3. Pressure Measurement 4. Forces Due to Static Fluid 5. Buoyancy and Stability 6. Flow of Fluid and
Chemistry Joke. Once you ve seen 6.02 x You ve seen a mole!
States of Matter Chemistry Joke Once you ve seen 6.02 x 10 23 atoms You ve seen a mole! Kinetic Theory Kinetic Theory explains the states of matter based on the concept that the particles in all forms
Supercritical Helium Cooling of the LHC Beam Screens
EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH European Laboratory for Particle Physics Large Hadron Collider Project LHC Project Report Supercritical Helium Cooling of the LHC Beam Screens Emmanuel Hatchadourian,,
Generation of vacuum (pumps) and measurements
Generation of vacuum (pumps) and measurements Generation of vacuum (pumps): ᴥ pumping systems general considerations on their use and match with physical quantities introduced for the dimensioning of vacuum
Liquids and solids are essentially incompressible substances and the variation of their density with pressure is usually negligible.
Properties of Fluids Intensive properties are those that are independent of the mass of a system i.e. temperature, pressure and density. Extensive properties are those whose values depend on the size of
PHY121 Physics for the Life Sciences I
PHY Physics for the Life Sciences I Lecture 0. Fluid flow: kinematics describing the motion. Fluid flow: dynamics causes and effects, Bernoulli s Equation 3. Viscosity and Poiseuille s Law for narrow tubes
Temperature Thermal Expansion Ideal Gas Law Kinetic Theory Heat Heat Transfer Phase Changes Specific Heat Calorimetry
Temperature Thermal Expansion Ideal Gas Law Kinetic Theory Heat Heat Transfer Phase Changes Specific Heat Calorimetry Zeroeth Law Two systems individually in thermal equilibrium with a third system (such
Chapter 8: Flow in Pipes
Objectives 1. Have a deeper understanding of laminar and turbulent flow in pipes and the analysis of fully developed flow 2. Calculate the major and minor losses associated with pipe flow in piping networks
(Refer Slide Time: 4:41)
Fluid Machines. Professor Sankar Kumar Som. Department Of Mechanical Engineering. Indian Institute Of Technology Kharagpur. Lecture-30. Basic Principle and Energy Transfer in Centrifugal Compressor Part
Fluid Mechanics Theory I
Fluid Mechanics Theory I Last Class: 1. Introduction 2. MicroTAS or Lab on a Chip 3. Microfluidics Length Scale 4. Fundamentals 5. Different Aspects of Microfluidcs Today s Contents: 1. Introduction to
Example Problems: 1.) What is the partial pressure of: Total moles = 13.2 moles 5.0 mol A 7.0 mol B 1.2 mol C Total Pressure = 3.
5.6 Dalton s Law of Partial Pressures Dalton s Law of Partial Pressure; The total pressure of a gas is the sum of all its parts. P total = P 1 + P + P 3 + P n Pressures are directly related to moles: n
THEORETICAL COMPETITION. 1A. SPRING CYLINDER WITH MASSIVE PISTON (5 points)
Question 1 1A. SPRING CYLINDER WITH MASSIVE PISTON (5 points) Consider n=2 moles of ideal Helium gas at a pressure P 0, volume V 0 and temperature T 0 = 300 K placed in a vertical cylindrical container
Vacuum. Kai Schwarzwälder, Institut für Physik Universität Basel October 6 th 2006
Physics,, Technology and Techniques of the Vacuum Kai Schwarzwälder, Institut für Physik Universität Basel October 6 th 2006 Outline Introduction and basics Defintion of Vacuum Vacuum A vacuum is a volume
Q1 Give answers to all of the following questions (5 marks each):
FLUID MECHANICS First Year Exam Solutions 03 Q Give answers to all of the following questions (5 marks each): (a) A cylinder of m in diameter is made with material of relative density 0.5. It is moored
Thermal Physics. Temperature (Definition #1): a measure of the average random kinetic energy of all the particles of a system Units: o C, K
Thermal Physics Internal Energy: total potential energy and random kinetic energy of the molecules of a substance Symbol: U Units: J Internal Kinetic Energy: arises from random translational, vibrational,
BALKAN PHYSICS LETTERS Bogazici University Press 15 November 2016 BPL, 24, , pp , (2016)
139 BALKAN PHYSICS LETTERS Bogazici University Press 15 November 2016 BPL, 24, 241016, pp. 139 145, (2016) VACUUM STUDIES ON ELECTRON GUN AND INJECTOR LINE OF TARLA FACILITY E. COŞGUN, E.P. DEMİRCİ, Ö.
Introduction to Aerodynamics. Dr. Guven Aerospace Engineer (P.hD)
Introduction to Aerodynamics Dr. Guven Aerospace Engineer (P.hD) Aerodynamic Forces All aerodynamic forces are generated wither through pressure distribution or a shear stress distribution on a body. The
Physics 111. Lecture 42 (Walker: 18.9) Entropy & Disorder Final Review. May 15, 2009
Physics 111 Lecture 42 (Walker: 18.9) Entropy & Disorder Final Review May 15, 2009 Review Session: Today, 3:10-4:00, TH230. Final exam, Monday May 18, 10:45-1:15. Lecture 42 1/32 The Physics 111 Final
Conductance measurement of a conical tube and calculation of the pressure distribution
Conductance measurement of a conical tube and calculation of the pressure distribution B. Mercier a Laboratoire de l Accélérateur Linéaire (LAL), Université Paris-Sud, Batiment 200, BP34, 9898 Orsay Cedex,
Energy and Energy Balances
Energy and Energy Balances help us account for the total energy required for a process to run Minimizing wasted energy is crucial in Energy, like mass, is. This is the Components of Total Energy energy
A Gas Uniformly fills any container. Easily compressed. Mixes completely with any other gas. Exerts pressure on its surroundings.
Chapter 5 Gases Chapter 5 A Gas Uniformly fills any container. Easily compressed. Mixes completely with any other gas. Exerts pressure on its surroundings. Copyright Cengage Learning. All rights reserved
Part A: 1 pts each, 10 pts total, no partial credit.
Part A: 1 pts each, 10 pts total, no partial credit. 1) (Correct: 1 pt/ Wrong: -3 pts). The sum of static, dynamic, and hydrostatic pressures is constant when flow is steady, irrotational, incompressible,
Fluids, Continuity, and Bernouli
Fluids, Continuity, and Bernouli Announcements: Exam Tomorrow at 7:30pm in same rooms as before. Web page: http://www.colorado.edu/physics/phys1110/phys1110_sp12/ Clicker question 1 A satellite, mass m,
Ⅰ. Vacuum Technology. 1. Introduction Vacuum empty in Greek Torricelli Vacuum 2 ) 760 mm. mbar 2 ) Enclosure. To pump. Thin Film Technology
Ⅰ. Vacuum Technology. Introduction Vacuum empty in Greek 643 Torricelli Vacuum 76 mm Hg Enclosure F ma 76mmHg 76Torr atm (76cm) (3.6g / cm 3 ) (98.665cm/sec ).33 6 dynes/ cm.33bar.33 5 ascal( N / m ).4696
Ch Kinetic Theory. 1.All matter is made of atoms and molecules that act like tiny particles.
Ch. 15.1 Kinetic Theory 1.All matter is made of atoms and molecules that act like tiny particles. Kinetic Theory 2.These tiny particles are always in motion. The higher the temperature, the faster the
REE 307 Fluid Mechanics II. Lecture 1. Sep 27, Dr./ Ahmed Mohamed Nagib Elmekawy. Zewail City for Science and Technology
REE 307 Fluid Mechanics II Lecture 1 Sep 27, 2017 Dr./ Ahmed Mohamed Nagib Elmekawy Zewail City for Science and Technology Course Materials drahmednagib.com 2 COURSE OUTLINE Fundamental of Flow in pipes
Chapter 4 DYNAMICS OF FLUID FLOW
Faculty Of Engineering at Shobra nd Year Civil - 016 Chapter 4 DYNAMICS OF FLUID FLOW 4-1 Types of Energy 4- Euler s Equation 4-3 Bernoulli s Equation 4-4 Total Energy Line (TEL) and Hydraulic Grade Line
Basic Fluid Mechanics
Basic Fluid Mechanics Chapter 6A: Internal Incompressible Viscous Flow 4/16/2018 C6A: Internal Incompressible Viscous Flow 1 6.1 Introduction For the present chapter we will limit our study to incompressible
Introduction to Fluid Machines and Compressible Flow Prof. S. K. Som Department of Mechanical Engineering Indian Institute of Technology, Kharagpur
Introduction to Fluid Machines and Compressible Flow Prof. S. K. Som Department of Mechanical Engineering Indian Institute of Technology, Kharagpur Lecture - 1 Introduction to Fluid Machines Well, good