Conservation & Acct Princ
Conservation & Acct Princ ES 201
Popular in Course
Popular in Engineering & Applied Science
This 10 page Class Notes was uploaded by Napoleon Turcotte II on Monday October 19, 2015. The Class Notes belongs to ES 201 at Rose-Hulman Institute of Technology taught by Staff in Fall. Since its upload, it has received 20 views. For similar materials see /class/225126/es-201-rose-hulman-institute-of-technology in Engineering & Applied Science at Rose-Hulman Institute of Technology.
Reviews for Conservation & Acct Princ
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 10/19/15
ES 201 Conservation amp Accountin Principles Fall 19992000 OBJECTIVES Chapter 1 Introduction Chapter 2 Basic Concepts Appendix A Solving Engineering Problems Appendix B Dimensions amp Units Define illustrate compare and contrast the following terms and concepts engineering analysis vs engineering design algorithm vs heuristic model as discussed in the notes system surroundings boundary control surface closed system control mass vs open system control volume interactions between a system and its surroundings isolated systern extensrve vs 1ntens1ve necessary and sufficient test for a property cycle steadystate system units amp dimensions primary vs secondary dimensions base units amp derived units unit conversion factor weight amp mass molar mass molecular weight mole mol krnol lbmol slugrnol etc local gravitational eld strength standard values g 980665 Nkg 100001bflbm 39 quot 39 391 to loca quot quot 39 39 quot standard values g 980665 ms2 32174 fts2 slug vs pound mass lbm or lbm vs pound force lbf or lbf continuum hypothesis macroscopic vs microscopic viewpoint accounting concept basic components accumulation within system transport across boundaries generation 11 39 quot vs finitetime vs rate forrn rate of accumulation rate of change relationship to an ordinary derivative with respect to time transport rate generation consumption rate conserved property vs nonconserved property 32174 lbfslug 439 I A 439 1 within systern obj70 1727a7b Page 1 of2 ES 201 Conservation amp Accountin Principles Fall 19992000 conservation laws vs accounting statements balances 2 Given a suf cient set of conversion factors convert the numerical value of a physical quantity given in one set of units to another speci ed set of units 3 Explain in words the difference between the mass of an object and its weight Demonstrate this understanding by applying Newton s second law F ma to solve problems involving weight mass and acceleration All answers must be given in standard units 4 List the seven components of the problem solving format methodology for engineering problem solving explain the signi cance of each part and use the format correctly in your problem solutions 5 Given a problem statement like HW Problems 21 and 2 1 apply the accounting concept to solve for the desired information Be sure to clearly indicate the system of interest the property or stuff to be counted and the time period of interest Problems should be worked showing suf cient steps so that the method used is clear 6 Give both a written and a symbolic description of the rateform of the accounting statement clearly indicating the accumulation transport and generation terms 7 Explain in words the difference between the quotrate of accumulation changequot and the quotrate of transport transport ratequot and quotrate of generation consumption consumption generation ratequot obj70 1727a7b Page 2 of 2 ES 201 Conservation amp Accountin Principles Fall 20002001 OBJECTIVES Conservation of Energy 1 De ne illustrate and compare and contrast the following terms and concepts WorkEnergy Principle relation to conservation of linear momentum Energy internal energy speci c intemal energy u mechanical energy gravitational potential energy speci c gravitational potential energy g2 kinetic energy speci c kinetic energy VZZ spring energy Work mechanism for transferring energy mechanical work vs thermodynamic work work Wvs power W path function reversible quasistatic work vs irreversible work types compressionexpansion pdV work elastic spring work electric workpower dc power ac power effective vs maximum values power factor shaft work Heat transfer mechanism for transferring energy heat transfer Q vs heat transfer rate adiabatic surface or boundary path function types of heat transfer conduction convection Newton s law of cooling convection heat transfer coef cient thermal radiation Application of Accounting Principle to Energy rate of accumulation of energy within the system amount of energyESyS IV 6 pdV ObjiEnergydoc v1 Page 1 ES 201 Conservation amp Accountin Principles N W 5 U 0quot gt1 9 0 Fall 20002001 where the speci c energy is de ned as e u V22 g2 transport rate of energy across non ow system boundaries transport rate of energy by heat transfer Heat transfer rate transport of energy by work at non ow boundaries W Power transport of energy by mass ow at ow boundaries transport rate of energy by work at ow boundaries 2 pvmm Z pvm0m ow power transport rate of energy mass ow 2 2 Zmu VYgzm Zmu V7gz0m Conservation of Energy rate form dE S V2 V2 61 QNztw WNetw 2 h Y gzmm Z 17 Y gzmgm where h u pv is a new property called enthalpy Given a mechanical system consisting of particles apply the WorkEnergy Principle where appropriate to solve problems where changes in mechanical energy kinetic potential and spring can be balanced with mechanical work done on the system Given a closed or open system and sufficient information about the properties of the system apply conservation of energy to determine changes in energy rates of change within the system and heat transfers heat transfer rates and work transfers of energy powers with the surroundings Given sufficient information determine the change in speci c internal energy Au and the change in Ah for a substance that can be modeled using one of the following substance models 0 Ideal gas with constant speci c heats o Incompressible substance with constant speci c heats Use this information in conjunction with objective 3 above Given a relation between pressure and volume for a compression expansion process where the system volume changes calculate the work done during the process Given a torque and a rotational speed calculate the shaft power transmitted by the shaft Given an electric current and the corresponding voltage difference across the terminals calculate the electric power supplied to or by the system You should be able to perform this calculation for both dc systems and for the effective rrns values of an ac system Given a numerical values for a typical energy or power quantity make the appropriate unit conversions to change the units to the requested values e g convert ftZs2 to Btulbm Given a device that operates in a closedperiodic or closedloop steadystate cycle 0 determine whether the device operates as a power cycle heat engine or a refrigerator or a heat pump and ObjiEnergydoc vl Page 2 ES 201 Conservation amp Accountin Principles Fall 20002001 o calculate the appropriate measure of performance for the speci c device ie a thermal efficiency for a power cycle and a coefficient of performance COP for a refrigerator or heat pump ObjiEnergydoc Vl Page 3 ES 201 Conservation amp A countin Principles Linear OBJECTIVES Conservation of Linear Momentum Define explain compare and contrast the following terms and concepts Particle vs Extended Body Rigid body Kinematic Relationships position velocity and acceleration Linear Momentum linear momentum of a particle 13 ml speci c linear momentum l inertial reference frame units of linear momentum Ns lbfs vector nature of linear momentum Application of Accounting Principle for Linear Momentum rate of accumulation of mass within the system amount of linear momentum within the system 13m l7 p dV transport rate of linear momentum across the system boundaries external forces body forces surface contact forces mass transport of linear momentum Z milI Z MZVZ In 0142 generationconsumption rate of linear momentum within the system Empirical result Linear momentum is conserved Conservation of Linear Momentum Equation dP t t t rate form 7 Z FEW Z rth Z MC in out Impulse Impulsive Force I4 J Rdt 2 Relationship of Conservation of Linear Momentum to Newton s Laws Center of mass Dry Friction A useful constitutive relation friction coel cient static vs kinetic sliding friction Obj705doc Page 1 of3 ES 201 Conservation amp A countin Principles Linear Stress normal vs shear stress Pressure Dimensions force area Units kPa Nm2 bar lbfin2 or psi lbfftz atrn Ways to report absolute vs gage vs vacuum Hydrostatic pressure Manometers Hydrostatic Forces on submerged surfaces Plane surfaces Magnitude of the resultant force pressure at centroid of surface area times area of surface Line of action of the force always normal to the surface Point of application always on the surface Moment of distributed hydrostatic force moment of resultant hydrostatic force Area moment of inertia Point of application Center of pressure 7t Centroid of surface area quotft Pressure Prism Approach Magnitude of the force volume of the pressure prism Line of action quotpasses through centroid of the pressure prismquot Plane surfaces line of action is perpendicular to surface Cuquot 1 urfa f and u in ti 1 and h ri ntal f r 1 Point of application Plane surface quotalways on surfacequot Cuquot 1 urfa f and u in ti 1 and h ri n Buoyancy Principle Way to compute hydrostatic force Net hydrostatic force on an object 2 Given a problem that can be solved using conservation of linear momentum you should be able to do the following 1 Select an appropriate system that can be used to find the important unknowns by using the information given in the problem Clearly identify the system and its boundaries on an appropriate drawing Carefully label all transports of linear momentum with the surroundings This is commonly called a freebody diagram 2 Indicate the time interval appropriate for the problem 3 Clearly identify and count the number of unknowns you are trying to find Define and use a unique symbol for each unknown 4 Develop a set of INDEPENDENT equations that are equal in number to the number of unknowns and are sufficient to solve for the unknowns These equations are developed using the conservation and accounting equations and the information given in the problem Carefully indicate how the Obj705doc Page 2 of3 ES 201 Conservation amp A countin Principles Linear information in the problem plus your assumptions are used to develop the problemspeci c equations from the general accounting and conservation principles 5 Solve for the unknown values 3 Starting with the conservation of linear momentum equation show what assumptions are necessary to develop the traditional result for a rigid body F ma 4 Given information about the acceleration of an object as a function of time use elementary calculus to develop an equation for the velocity and as a function of time 5 Given information about the velocity of an object as a function of time use elementary calculus to develop an equation for the position as a function of time 6 Use the concepts embodied in the conservation of momentum equation including transport and storage of linear momentum to explain the behavior of a device or system 7 Given a problem that involves friction use both sliding and static friction forces where appropriate to explain the motion andor forces in the system 8 Given a manometer with one or more uids determine the pressure differences absolute pressures and gage pressures indicated by the manometer 9 Given a pressure measurement reported as an absolute value convert it to either a gage or vacuum value and given a pressure measurement reported as either a gage or vacuum value convert it to an absolute value 10 Given a static body of uid determine the hydrostatic pressure at any point in the body 11 Given a plane surface submerged in a uid determine the line of action the magnitude and the point of application of the resultant hydrostatic force Obj705doc Page 3 of3 Learning Objectives Page 1 of2 Chapter 8 Chapter 8 Entropy Production and Accounting 1 Define illustrate and explain the following terms and concepts Second Law of Thermodynamics Reversible processes internally reversible vs internally irreversible Entropy units kJK Btu0R specific entropy 8 units kJK39kg Btu0R 39lbm Thermodynamic temperature Application of Accounting Principle for Entropy rate of accumulation of entropy Within the s stem amount of entropy Within the system SW S pdV transport rate of entropy across system boundaries transport rate of entropy by heat transfer 2 512 b J transport rate of entropy by mass flow 2 WLLSL 7 Z rhese in out productionconsumption of entropy EMPIRICAL EVIDENCE Entropy can only be produced and in the limit of an internally reversible process entropy is conserved Rate of entropy production gt0 Internally irreversible 0 Internally reversible Carnot Efficiency for a Power Cycle lsentropic Processs Apply the accounting equation for entropy in conjunction With the conservation of energy equation to calculate the entropy generation rate or entropy generation for a steadystate device or cycle Learning Objectives Page 2 of2 Chapter 8 530 tb 01 E7 1 Given sufficient information determine the specific entropy change As for a substance When one of the following models apply ldeal gas With roomtemperature specific heats l t With p atuie specific heats 1 Apply the entropy accounting equation in conjunction With the conservation of energy equation to calculate the entropy generation or the entropy generation rate for a system When all other necessary information is known Apply the accounting equation for entropy in conjunction With the conservation of energy equation to determine the theoretical best performance ie theoretical maximum thermal efficiency or coefficient of performance for a cycle Determine if a specific device or system is operating in a reversible fashion an irreversible fashion or is not physically possible Evalute the performance of a device or system When it is operating in an internally reversible fashion
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'