We will try to get familiar with a heat pump, and try to determine its performance coefficient under different circumstances.

Size: px
Start display at page:

Download "We will try to get familiar with a heat pump, and try to determine its performance coefficient under different circumstances."

Transcription

1 C4. Heat Pump I. OBJECTIVE OF THE EXPERIMENT We will try to get familiar with a heat pump, and try to determine its performance coefficient under different circumstances. II. INTRODUCTION II.1. Thermodynamic Background Thermodynamics study the connection between thermal and mechanical phenomena. In most thermodynamic problems, we are interested in systems, i.e. a set of bodies that undergo different transformations. These transformations are generally the result of work or heat transfer between systems, or between parts of a same system. As a result, we observe a temperature change, a variation in pressure or even a phase change. More generally, this results in a change in thermodynamic variables. First principle: ΔU = ΔW + ΔQ where ΔU represents the total energy variation between two states of the system (independently of the path used to get there) and ΔW and ΔQ correspond to the work and heat exchange between both states, while following a specific path. Even though this conservation law cannot be directly proven, numerous experiments and scientific conclusions based on it prove its validity. The first principle doesn t exclude that within a given system, a certain amount of heat can be entirely transformed into work (ΔU = O so ΔW=-ΔQ). This, however, is not verified experimentally. Second principle The second principle limits the conversion of heat into work. Most notably, it states the impossibility for a body to transfer heat to a body at higher temperature without external work being applied. In other words, and according to experience, a system will have a natural tendency to reach a thermal equilibrium by transferring heat from the hot source to the cold source (fig. 1). To achieve the opposite transfer, we need an external source of energy (fig.2). This is how a heat pump works.

2 EPFL-TRAVAUX PRATIQUES DE PHYSIQUE C4-2 Tc Tc Qc M W Tf T f Q f Fig. 1 : If both sources are put in contact, there is a natural heat transfer from the hot source to the cold source Tc > Tf. Fig. 2 : If we would like a heat transfer from the cold source to the hot source (Tc > Tf), then a machine is required, that supplies a work W II.2. Principle of the heat pump. The basic idea behind a heat pump is the following: a condensable cooling fluid goes through a closed system. It will perform several heat exchanges with the surrounding environment, and will also undergo successive liquid/gas phase transformations back and forth. When it evaporates, it absorbs calories, and it loses some when condensing. For those transformations to happen in both heat exchange modules, that we will call respectively condenser (hot source, Tc) and evaporator (cold source Tf), we need to compress the gas between the heat exchange modules in one direction, and release it in the other. Picking the fluid depends on the temperatures to reach, the characteristics of the compressor, the size of the heat exchange modules, the heat transfer coefficient of the cooling fluid, its latent heat, and finally its specific volume. The cold source (the evaporator, i.e. where we extract the heat) can be, for example, a water stream, the ground, or even air. III. DESCRIPTION OF THE SETUP The cooling fluid used in the heat pump is "Freon 12" whose boiling point is 243,37 K and latent heat 39,94 cal/g in one atmosphere of pressure. Let s now look into the different stages of the cycle, by referring ourselves to the heat pump diagram (Fig. 3): The freon gases are compressed in a compressor (1), which strongly increases its temperature. In the condenser, the freon liquefies, releasing its latent heat to the liquid in the dewar (2). The liquefied freon the goes through a purificator, to eliminate all vapor bubbles still contained in it (3). The liquid then goes through an expansion valve (4) that releases a certain amount of liquid in the evaporator (5). The freon evaporates, and extracts the necessary heat from the liquid of the dewar (5). The low pressure found in the evaporator is created by the suction of the compressor. The correct setting of the expansion valve is regulated by a thermocouple (6) that measures the temperature difference between the cooling fluid entering and exiting the evaporator. If this difference isn t large enough, the expansion valve reduces its throughput. The vaporized freon then re-enters the compressor, and the cycle starts over.

3 EPFL-TRAVAUX PRATIQUES DE PHYSIQUE C4-3 The amount of heat transferred from the evaporator to the condenser equates to approximately three times as much energy, than the electric energy consumed by the compressor. Despite this fact, this conclusion isn t contrary to energy conservation laws. The remaining two thirds of energy come from the evaporator. Fig. 3: Diagram of the heat pump To quantify the performance of a heat pump, we define a performance coefficient or efficiency coefficient ε equal to the ratio of transferred heat to the amount of work provided to the system. ε = Q c W ε > 1 W is the work supplied to the system, Qc the amount of heat transferred over one cycle and Tc and Tf are the temperatures of the hot and cold source respectively. The experimental performance coefficient ε is noticeably smaller than the theoretical value ε th due to some irreversible phenomena encountered in the real thermodynamic cycle. T c ε th = T c T f

4 EPFL-TRAVAUX PRATIQUES DE PHYSIQUE C4-4 IV. THERMODYNAMIC DIAGRAMS At low temperatures, gases must be treated like real fluids, whose behavior can be analyzed by a Clapeyron diagram (Fig..4). Fig. 4: Clapeyron diagram Mathematically, the real gas can be described by the Van der Waals equation: P + a V 2 V - b = R T for 1 mol of gas a where V 2 describes the attraction between molecules, and b represents the specific volume of individual molecules. We can also calculate Tc, i.e. the temperature of the isotherm that has a horizontal tangent at its inflexion point, where V = Vc. P V T = Tc = 0 - R T c V c - b a V c 3 = 0 et 2 P = 0 2 V T = Tc 2 R T c V c - b 3-6a V c 4 = 0 thus T c = 8 a 27 R b, V c = 3 b et P c = a 27 b 2 The gas liquefaction is only possible if T < Tc. From the diagram in figure 4, let s suppose two isotherms T1 et T2 below Tc, and let s make the Van der Waals gas follow the cyclic transformations ABCDA: A -> B adiabatic compression ; B -> B' isobaric cooling, followed by an isothermal liquefaction T1 (B' -> C') and isobaric cooling of the liquid (C' -> C); C -> D adiabatic relaxation; (D -> D') isothermal evaporation on T2, D' -> A followed by an isobaric heating. Over a cycle, the gas extracts heat during the evaporation on the isotherm T2, and releases that heat during the liquefaction on the isotherm T1. Work is supplied to the gas during the adiabatic compression (A -> B).

5 EPFL-TRAVAUX PRATIQUES DE PHYSIQUE C4-5 Mollier Diagram: lnp vs. h (Fig. 5). When working on a heat pump or cooling machine, the state changes of the gas are described using Mollier diagrams, on which we plot pressure P on a logarithmic y-axis, and enthalpy on the x-axis. Fig. 5: Mollier diagram (lnp vs. h) of freon R12 gas. Recall that the enthalpy H is defined by the internal energy U, the pressure P and the volume V, according to the equation: H = U + P V In this graph, curves of constant pressure are horizontal lines, and curves of constant enthalpy are vertical lines. In the liquid-gas region, i.e. under the saturation line, isothermal lines are, like isobaric lines, horizontal. Curves of constant gas to liquid ratio intersect isothermal curves according to a linear graduation. While the heat pump is running, we measure the condensation and evaporation pressures Pcond and Pevap, as well as the temperatures of the gas before compression, after compression, and before relaxation T1, T2 and T3. These five parameters allow us to plot the thermodynamic cycle (T 1 ->T2-> T3 ) on the Mollier diagram. (Fig. 5). Isotherms in the part of Mollier s diagram describing liquid are vertical lines! From this, we can deduce three value of the specific enthalpy. h1 before compression, h2 after compression, and finally h3 before evaporation. These three values allow us to determine the maximal performance coefficient that can be achieved using the given gas. The thermodynamic limit is:

6 EPFL-TRAVAUX PRATIQUES DE PHYSIQUE C4-6 Ex.: The cycle in figure 5 yields: ε M = ε M = h 2 h 3 h 2 h = 4.7 V. SUGGESTED EXPERIMENTS Measuring the performance coefficient under different circumstances 1) Let the heat pump run for 30 minutes, using a finite reservoir. Every minute, take note of the temperatures in both dewars, the temperatures of the gas (T 1,T 2,T 3 ), the condensation and evaporation pressures, as well as the electrical power supplied to the compressor (for a total of, 5 temperature, 2 pressures, 1 voltage and 1 current). a. Plot a graph of the temperature variations over time, and calculate the amount of heat transferred from the cold source to the hot source. Compare it with the work the compressor used. b. Make a Mollier diagram of the cycle in the steady state (copies of the diagram are available at the lab). Determine the gas maximal performance coefficient. c. Determine the heat pump s performance coefficient, and compare it to the best result we could expect (Carnot cycle). Discuss. d. If there is enough time, start over now that the compressor is hot (but do par 2) first). Did the heat pump perform better? 2) Do the same experiment, but this time with an infinite reservoir (after having changed the water in both containers) 3) Comment on the signification of the three different performance coefficients Using the setup (see fig. 6) Fill the dewars with 5 liters of water, by hitting the filling switch. Then, start the mixing. To do so, put both mix-empty switches onto mix (brassage), and activate the pumping in both fillers (using the pumping switches). Verify that the temperature has stabilized. Plug in the compressor in order to be able to read the amount of power that it uses. Launch the compressor and the stopwatch simultaneously. DO NOT let the water in cold source freeze. Stop the compressor before reaching 0 C. For the infinite reservoir, place the mix-empty switch of the cold source on mix, and let the water flow (filling switch) in order for the volume to remain constant.

7 EPFL-TRAVAUX PRATIQUES DE PHYSIQUE C4-7 Fig.6 : Image of the heat pump VI. BIBLIOGRAPHY 1.FEYNMAN : "Cours de Physique - mécanique 2" (p. 264 et suivantes) InterEditions, Paris 2.A. HOUBER ECHTS : "La thermodynamique technique", tomes 1 et 2. Vander Editeurs. 3.G. BRUHAT : "Cours de Physique Générale - Thermodynamique". Masson & Cie, Editeurs.

The Second Law of Thermodynamics

The Second Law of Thermodynamics The Second aw of Thermodynamics The second law of thermodynamics asserts that processes occur in a certain direction and that the energy has quality as well as quantity. The first law places no restriction

More information

UNIT 2 REFRIGERATION CYCLE

UNIT 2 REFRIGERATION CYCLE UNIT 2 REFRIGERATION CYCLE Refrigeration Cycle Structure 2. Introduction Objectives 2.2 Vapour Compression Cycle 2.2. Simple Vapour Compression Refrigeration Cycle 2.2.2 Theoretical Vapour Compression

More information

We will study the temperature-pressure diagram of nitrogen, in particular the triple point.

We will study the temperature-pressure diagram of nitrogen, in particular the triple point. K4. Triple Point of Nitrogen I. OBJECTIVE OF THE EXPERIMENT We will study the temperature-pressure diagram of nitrogen, in particular the triple point. II. BAKGROUND THOERY States of matter Matter is made

More information

The Second Law of Thermodynamics

The Second Law of Thermodynamics Objectives MAE 320 - Chapter 6 The Second Law of Thermodynamics The content and the pictures are from the text book: Çengel, Y. A. and Boles, M. A., Thermodynamics: An Engineering Approach, McGraw-Hill,

More information

The First Law of Thermodynamics

The First Law of Thermodynamics Thermodynamics The First Law of Thermodynamics Thermodynamic Processes (isobaric, isochoric, isothermal, adiabatic) Reversible and Irreversible Processes Heat Engines Refrigerators and Heat Pumps The Carnot

More information

REFRIGERATION (& HEAT PUMPS)

REFRIGERATION (& HEAT PUMPS) REFRIGERATION (& HEAT PUMPS) Refrigeration is the 'artificial' extraction of heat from a substance in order to lower its temperature to below that of its surroundings Primarily, heat is extracted from

More information

Thermodynamics - Example Problems Problems and Solutions

Thermodynamics - Example Problems Problems and Solutions Thermodynamics - Example Problems Problems and Solutions 1 Examining a Power Plant Consider a power plant. At point 1 the working gas has a temperature of T = 25 C. The pressure is 1bar and the mass flow

More information

FUNDAMENTALS OF ENGINEERING THERMODYNAMICS

FUNDAMENTALS OF ENGINEERING THERMODYNAMICS FUNDAMENTALS OF ENGINEERING THERMODYNAMICS System: Quantity of matter (constant mass) or region in space (constant volume) chosen for study. Closed system: Can exchange energy but not mass; mass is constant

More information

Chapter 8 Maxwell relations and measurable properties

Chapter 8 Maxwell relations and measurable properties Chapter 8 Maxwell relations and measurable properties 8.1 Maxwell relations Other thermodynamic potentials emerging from Legendre transforms allow us to switch independent variables and give rise to alternate

More information

Phys222 W11 Quiz 1: Chapters 19-21 Keys. Name:

Phys222 W11 Quiz 1: Chapters 19-21 Keys. Name: Name:. In order for two objects to have the same temperature, they must a. be in thermal equilibrium.

More information

Chapter 18 Temperature, Heat, and the First Law of Thermodynamics. Problems: 8, 11, 13, 17, 21, 27, 29, 37, 39, 41, 47, 51, 57

Chapter 18 Temperature, Heat, and the First Law of Thermodynamics. Problems: 8, 11, 13, 17, 21, 27, 29, 37, 39, 41, 47, 51, 57 Chapter 18 Temperature, Heat, and the First Law of Thermodynamics Problems: 8, 11, 13, 17, 21, 27, 29, 37, 39, 41, 47, 51, 57 Thermodynamics study and application of thermal energy temperature quantity

More information

The final numerical answer given is correct but the math shown does not give that answer.

The final numerical answer given is correct but the math shown does not give that answer. Note added to Homework set 7: The solution to Problem 16 has an error in it. The specific heat of water is listed as c 1 J/g K but should be c 4.186 J/g K The final numerical answer given is correct but

More information

Physics 5D - Nov 18, 2013

Physics 5D - Nov 18, 2013 Physics 5D - Nov 18, 2013 30 Midterm Scores B } Number of Scores 25 20 15 10 5 F D C } A- A A + 0 0-59.9 60-64.9 65-69.9 70-74.9 75-79.9 80-84.9 Percent Range (%) The two problems with the fewest correct

More information

Chapter 10 Temperature and Heat

Chapter 10 Temperature and Heat Chapter 10 Temperature and Heat What are temperature and heat? Are they the same? What causes heat? What Is Temperature? How do we measure temperature? What are we actually measuring? Temperature and Its

More information

Answer, Key Homework 6 David McIntyre 1

Answer, Key Homework 6 David McIntyre 1 Answer, Key Homework 6 David McIntyre 1 This print-out should have 0 questions, check that it is complete. Multiple-choice questions may continue on the next column or page: find all choices before making

More information

Supplementary Notes on Entropy and the Second Law of Thermodynamics

Supplementary Notes on Entropy and the Second Law of Thermodynamics ME 4- hermodynamics I Supplementary Notes on Entropy and the Second aw of hermodynamics Reversible Process A reversible process is one which, having taken place, can be reversed without leaving a change

More information

PG Student (Heat Power Engg.), Mechanical Engineering Department Jabalpur Engineering College, India. Jabalpur Engineering College, India.

PG Student (Heat Power Engg.), Mechanical Engineering Department Jabalpur Engineering College, India. Jabalpur Engineering College, India. International Journal of Emerging Trends in Engineering and Development Issue 3, Vol. (January 23) EFFECT OF SUB COOLING AND SUPERHEATING ON VAPOUR COMPRESSION REFRIGERATION SYSTEMS USING 22 ALTERNATIVE

More information

Exergy: the quality of energy N. Woudstra

Exergy: the quality of energy N. Woudstra Exergy: the quality of energy N. Woudstra Introduction Characteristic for our society is a massive consumption of goods and energy. Continuation of this way of life in the long term is only possible if

More information

Type: Single Date: Homework: READ 12.8, Do CONCEPT Q. # (14) Do PROBLEMS (40, 52, 81) Ch. 12

Type: Single Date: Homework: READ 12.8, Do CONCEPT Q. # (14) Do PROBLEMS (40, 52, 81) Ch. 12 Type: Single Date: Objective: Latent Heat Homework: READ 12.8, Do CONCEPT Q. # (14) Do PROBLEMS (40, 52, 81) Ch. 12 AP Physics B Date: Mr. Mirro Heat and Phase Change When bodies are heated or cooled their

More information

Introduction to the Ideal Gas Law

Introduction to the Ideal Gas Law Course PHYSICS260 Assignment 5 Consider ten grams of nitrogen gas at an initial pressure of 6.0 atm and at room temperature. It undergoes an isobaric expansion resulting in a quadrupling of its volume.

More information

ASSESSMENT OF THE SUBCOOLING CAPABILITIES OF A THERMOELECTRIC DEVICE IN A VAPOR COMPRESSION REFRIGERATION SYSTEM

ASSESSMENT OF THE SUBCOOLING CAPABILITIES OF A THERMOELECTRIC DEVICE IN A VAPOR COMPRESSION REFRIGERATION SYSTEM Universitatea de Ştiinţe Agricole şi Medicină Veterinară Iaşi ASSESSMENT OF E SUBCOOLING CAPABILITIES OF A ERMOELECTRIC DEVICE IN A VAPOR COMPRESSION REFRIGERATION SYSTEM R. ROŞCA 1, I. ŢENU 1, P. CÂRLESCU

More information

a) Use the following equation from the lecture notes: = ( 8.314 J K 1 mol 1) ( ) 10 L

a) Use the following equation from the lecture notes: = ( 8.314 J K 1 mol 1) ( ) 10 L hermodynamics: Examples for chapter 4. 1. One mole of nitrogen gas is allowed to expand from 0.5 to 10 L reversible and isothermal process at 300 K. Calculate the change in molar entropy using a the ideal

More information

Stirling heat engine Internal combustion engine (Otto cycle) Diesel engine Steam engine (Rankine cycle) Kitchen Refrigerator

Stirling heat engine Internal combustion engine (Otto cycle) Diesel engine Steam engine (Rankine cycle) Kitchen Refrigerator Lecture. Real eat Engines and refrigerators (Ch. ) Stirling heat engine Internal combustion engine (Otto cycle) Diesel engine Steam engine (Rankine cycle) Kitchen Refrigerator Carnot Cycle - is not very

More information

16. Heat Pipes in Electronics Cooling (2)

16. Heat Pipes in Electronics Cooling (2) 16. Heat Pipes in Electronics Cooling (2) 16.1 Pulsating Heat Pipes 16.1.1Introduction Conventional heat pipe technology has been successfully applied in the last thirty years for the thermal management

More information

THE KINETIC THEORY OF GASES

THE KINETIC THEORY OF GASES Chapter 19: THE KINETIC THEORY OF GASES 1. Evidence that a gas consists mostly of empty space is the fact that: A. the density of a gas becomes much greater when it is liquefied B. gases exert pressure

More information

Measurement And Application of Performance Characteristics Of A Free Piston Stirling Cooler

Measurement And Application of Performance Characteristics Of A Free Piston Stirling Cooler Purdue University Purdue e-pubs International Refrigeration and Air Conditioning Conference School of Mechanical Engineering 00 Measurement And Application of Performance Characteristics Of A Free Piston

More information

Chapter 17: Change of Phase

Chapter 17: Change of Phase Chapter 17: Change of Phase Conceptual Physics, 10e (Hewitt) 3) Evaporation is a cooling process and condensation is A) a warming process. B) a cooling process also. C) neither a warming nor cooling process.

More information

How does solar air conditioning work?

How does solar air conditioning work? How does solar air conditioning work? In a conventional air conditioning system; The working fluid arrives at the compressor as a cool, low-pressure gas. The compressor is powered by electricity to squeeze

More information

Refrigeration Basics 101. By: Eric Nelson

Refrigeration Basics 101. By: Eric Nelson Refrigeration Basics 101 By: Eric Nelson Basics Refrigeration is the removal of heat from a material or space, so that it s temperature is lower than that of it s surroundings. When refrigerant absorbs

More information

C H A P T E R T W O. Fundamentals of Steam Power

C H A P T E R T W O. Fundamentals of Steam Power 35 C H A P T E R T W O Fundamentals of Steam Power 2.1 Introduction Much of the electricity used in the United States is produced in steam power plants. Despite efforts to develop alternative energy converters,

More information

A car air-conditioning system based on an absorption refrigeration cycle using energy from exhaust gas of an internal combustion engine

A car air-conditioning system based on an absorption refrigeration cycle using energy from exhaust gas of an internal combustion engine A car air-conditioning system based on an absorption refrigeration cycle using energy from exhaust gas of an internal combustion engine G Vicatos J Gryzagoridis S Wang Department of Mechanical Engineering,

More information

Energy savings in commercial refrigeration. Low pressure control

Energy savings in commercial refrigeration. Low pressure control Energy savings in commercial refrigeration equipment : Low pressure control August 2011/White paper by Christophe Borlein AFF and l IIF-IIR member Make the most of your energy Summary Executive summary

More information

IDEAL AND NON-IDEAL GASES

IDEAL AND NON-IDEAL GASES 2/2016 ideal gas 1/8 IDEAL AND NON-IDEAL GASES PURPOSE: To measure how the pressure of a low-density gas varies with temperature, to determine the absolute zero of temperature by making a linear fit to

More information

Mohan Chandrasekharan #1

Mohan Chandrasekharan #1 International Journal of Students Research in Technology & Management Exergy Analysis of Vapor Compression Refrigeration System Using R12 and R134a as Refrigerants Mohan Chandrasekharan #1 # Department

More information

PERFORMANCE ANALYSIS OF VAPOUR COMPRESSION REFRIGERATION SYSTEM WITH R404A, R407C AND R410A

PERFORMANCE ANALYSIS OF VAPOUR COMPRESSION REFRIGERATION SYSTEM WITH R404A, R407C AND R410A Int. J. Mech. Eng. & Rob. Res. 213 Jyoti Soni and R C Gupta, 213 Research Paper ISSN 2278 149 www.ijmerr.com Vol. 2, No. 1, January 213 213 IJMERR. All Rights Reserved PERFORMANCE ANALYSIS OF VAPOUR COMPRESSION

More information

UNDERSTANDING REFRIGERANT TABLES

UNDERSTANDING REFRIGERANT TABLES Refrigeration Service Engineers Society 1666 Rand Road Des Plaines, Illinois 60016 UNDERSTANDING REFRIGERANT TABLES INTRODUCTION A Mollier diagram is a graphical representation of the properties of a refrigerant,

More information

Optimal operation of simple refrigeration cycles Part I: Degrees of freedom and optimality of sub-cooling

Optimal operation of simple refrigeration cycles Part I: Degrees of freedom and optimality of sub-cooling Computers and Chemical Engineering 31 (2007) 712 721 Optimal operation of simple refrigeration cycles Part I: Degrees of freedom and optimality of sub-cooling Jørgen Bauck Jensen, Sigurd Skogestad Department

More information

THERMODYNAMICS TUTORIAL 5 HEAT PUMPS AND REFRIGERATION. On completion of this tutorial you should be able to do the following.

THERMODYNAMICS TUTORIAL 5 HEAT PUMPS AND REFRIGERATION. On completion of this tutorial you should be able to do the following. THERMODYNAMICS TUTORIAL 5 HEAT PUMPS AND REFRIGERATION On completion of this tutorial you should be able to do the following. Discuss the merits of different refrigerants. Use thermodynamic tables for

More information

Air-sourced 90 Hot Water Supplying Heat Pump "HEM-90A"

Air-sourced 90 Hot Water Supplying Heat Pump HEM-90A Air-sourced 90 Hot Water Supplying Heat Pump "HEM-90A" Takahiro OUE *1, Kazuto OKADA *1 *1 Refrigeration System & Energy Dept., Compressor Div., Machinery Business Kobe Steel has developed an air-sourced

More information

Every mathematician knows it is impossible to understand an elementary course in thermodynamics. ~V.I. Arnold

Every mathematician knows it is impossible to understand an elementary course in thermodynamics. ~V.I. Arnold Every mathematician knows it is impossible to understand an elementary course in thermodynamics. ~V.I. Arnold Radiation Radiation: Heat energy transmitted by electromagnetic waves Q t = εσat 4 emissivity

More information

Condensers & Evaporator Chapter 5

Condensers & Evaporator Chapter 5 Condensers & Evaporator Chapter 5 This raises the condenser temperature and the corresponding pressure thereby reducing the COP. Page 134 of 263 Condensers & Evaporator Chapter 5 OBJECTIVE QUESTIONS (GATE,

More information

) and mass of each particle is m. We make an extremely small

) and mass of each particle is m. We make an extremely small Umeå Universitet, Fysik Vitaly Bychkov Prov i fysik, Thermodynamics, --6, kl 9.-5. Hjälpmedel: Students may use any book including the textbook Thermal physics. Present your solutions in details: it will

More information

Analysis of Ammonia Water (NH3-H2O) Vapor Absorption Refrigeration System based on First Law of Thermodynamics

Analysis of Ammonia Water (NH3-H2O) Vapor Absorption Refrigeration System based on First Law of Thermodynamics International Journal of Scientific & Engineering Research Volume 2, Issue 8, August-2011 1 Analysis of Ammonia Water (NH3-H2O) Vapor Absorption Refrigeration System based on First Law of Thermodynamics

More information

Lesson. 11 Vapour Compression Refrigeration Systems: Performance Aspects And Cycle Modifications. Version 1 ME, IIT Kharagpur 1

Lesson. 11 Vapour Compression Refrigeration Systems: Performance Aspects And Cycle Modifications. Version 1 ME, IIT Kharagpur 1 Lesson Vapour Compression Refrigeration Systems: Performance Aspects And Cycle Modifications Version ME, IIT Kharagpur The objectives of this lecture are to discuss. Performance aspects of SSS cycle and

More information

A Comparison of an R22 and an R410A Air Conditioner Operating at High Ambient Temperatures

A Comparison of an R22 and an R410A Air Conditioner Operating at High Ambient Temperatures R2-1 A Comparison of an R22 and an R410A Air Conditioner Operating at High Ambient Temperatures W. Vance Payne and Piotr A. Domanski National Institute of Standards and Technology Building Environment

More information

Thermodynamics AP Physics B. Multiple Choice Questions

Thermodynamics AP Physics B. Multiple Choice Questions Thermodynamics AP Physics B Name Multiple Choice Questions 1. What is the name of the following statement: When two systems are in thermal equilibrium with a third system, then they are in thermal equilibrium

More information

Physical Chemistry Laboratory I CHEM 445 Experiment 6 Vapor Pressure of a Pure Liquid (Revised, 01/09/06)

Physical Chemistry Laboratory I CHEM 445 Experiment 6 Vapor Pressure of a Pure Liquid (Revised, 01/09/06) 1 Physical Chemistry Laboratory I CHEM 445 Experiment 6 Vapor Pressure of a Pure Liquid (Revised, 01/09/06) The vapor pressure of a pure liquid is an intensive property of the compound. That is, the vapor

More information

APPLIED THERMODYNAMICS TUTORIAL 1 REVISION OF ISENTROPIC EFFICIENCY ADVANCED STEAM CYCLES

APPLIED THERMODYNAMICS TUTORIAL 1 REVISION OF ISENTROPIC EFFICIENCY ADVANCED STEAM CYCLES APPLIED THERMODYNAMICS TUTORIAL 1 REVISION OF ISENTROPIC EFFICIENCY ADVANCED STEAM CYCLES INTRODUCTION This tutorial is designed for students wishing to extend their knowledge of thermodynamics to a more

More information

Automobile Air Conditioning Primer

Automobile Air Conditioning Primer Automobile Air Conditioning Primer An air conditioner is basically a refrigerator without the insulated box. It uses the evaporation of a refrigerant, like Freon, to provide cooling. The mechanics of the

More information

جامعة البلقاء التطبيقية

جامعة البلقاء التطبيقية AlBalqa Applied University تا سست عام 997 The curriculum of associate degree in Air Conditioning, Refrigeration and Heating Systems consists of (7 credit hours) as follows: Serial No. Requirements First

More information

Using Excel (Microsoft Office 2007 Version) for Graphical Analysis of Data

Using Excel (Microsoft Office 2007 Version) for Graphical Analysis of Data Using Excel (Microsoft Office 2007 Version) for Graphical Analysis of Data Introduction In several upcoming labs, a primary goal will be to determine the mathematical relationship between two variable

More information

Physical Chemistry Practical Course, Oxford University. Determination of the Surface Area of Alumina by Nitrogen Adsorption at 77K (4 points)

Physical Chemistry Practical Course, Oxford University. Determination of the Surface Area of Alumina by Nitrogen Adsorption at 77K (4 points) Physical Chemistry Practical Course, Oxford University 1.06 Determination of the Surface Area of Alumina by Nitrogen Adsorption at 77K (4 points) What you will do In this experiment you will study the

More information

Open Cycle Refrigeration System

Open Cycle Refrigeration System Chapter 9 Open Cycle Refrigeration System Copy Right By: Thomas T.S. Wan 温 到 祥 著 Sept. 3, 2008 All rights reserved An open cycle refrigeration system is that the system is without a traditional evaporator.

More information

Fog and Cloud Development. Bows and Flows of Angel Hair

Fog and Cloud Development. Bows and Flows of Angel Hair Fog and Cloud Development Bows and Flows of Angel Hair 1 Ch. 5: Condensation Achieving Saturation Evaporation Cooling of Air Adiabatic and Diabatic Processes Lapse Rates Condensation Condensation Nuclei

More information

An analysis of a thermal power plant working on a Rankine cycle: A theoretical investigation

An analysis of a thermal power plant working on a Rankine cycle: A theoretical investigation An analysis of a thermal power plant working on a Rankine cycle: A theoretical investigation R K Kapooria Department of Mechanical Engineering, BRCM College of Engineering & Technology, Bahal (Haryana)

More information

ME 315 - Heat Transfer Laboratory. Experiment No. 7 ANALYSIS OF ENHANCED CONCENTRIC TUBE AND SHELL AND TUBE HEAT EXCHANGERS

ME 315 - Heat Transfer Laboratory. Experiment No. 7 ANALYSIS OF ENHANCED CONCENTRIC TUBE AND SHELL AND TUBE HEAT EXCHANGERS ME 315 - Heat Transfer Laboratory Nomenclature Experiment No. 7 ANALYSIS OF ENHANCED CONCENTRIC TUBE AND SHELL AND TUBE HEAT EXCHANGERS A heat exchange area, m 2 C max maximum specific heat rate, J/(s

More information

Specific Heat (slope and steepness)

Specific Heat (slope and steepness) 1 Specific Heat (slope and steepness) 10 pages. According to the Physical Science text book, the Specific Heat of a material is DEFINED as the following: Specific heat is the amount of heat energy required

More information

Experiment 12E LIQUID-VAPOR EQUILIBRIUM OF WATER 1

Experiment 12E LIQUID-VAPOR EQUILIBRIUM OF WATER 1 Experiment 12E LIQUID-VAPOR EQUILIBRIUM OF WATER 1 FV 6/26/13 MATERIALS: PURPOSE: 1000 ml tall-form beaker, 10 ml graduated cylinder, -10 to 110 o C thermometer, thermometer clamp, plastic pipet, long

More information

So T decreases. 1.- Does the temperature increase or decrease? For 1 mole of the vdw N2 gas:

So T decreases. 1.- Does the temperature increase or decrease? For 1 mole of the vdw N2 gas: 1.- One mole of Nitrogen (N2) has been compressed at T0=273 K to the volume V0=1liter. The gas goes through the free expansion process (Q = 0, W = 0), in which the pressure drops down to the atmospheric

More information

Liquefied Natural Gas (LNG)

Liquefied Natural Gas (LNG) Graduate Diploma in Petroleum Studies Major in Liquefied Natural Gas (LNG) INDUCTION Launching ceremony Week 39, 2012 Administration / Plant visit / Fundamentals of LNG and LNG main risks awareness Module

More information

Heat and Work. First Law of Thermodynamics 9.1. Heat is a form of energy. Calorimetry. Work. First Law of Thermodynamics.

Heat and Work. First Law of Thermodynamics 9.1. Heat is a form of energy. Calorimetry. Work. First Law of Thermodynamics. Heat and First Law of Thermodynamics 9. Heat Heat and Thermodynamic rocesses Thermodynamics is the science of heat and work Heat is a form of energy Calorimetry Mechanical equivalent of heat Mechanical

More information

Development of a model for the simulation of Organic Rankine Cycles based on group contribution techniques

Development of a model for the simulation of Organic Rankine Cycles based on group contribution techniques ASME Turbo Expo Vancouver, June 6 10 2011 Development of a model for the simulation of Organic Rankine ycles based on group contribution techniques Enrico Saverio Barbieri Engineering Department University

More information

FXA 2008. Candidates should be able to : Define and apply the concept of specific heat capacity. Select and apply the equation : E = mcδθ

FXA 2008. Candidates should be able to : Define and apply the concept of specific heat capacity. Select and apply the equation : E = mcδθ UNIT G484 Module 3 4.3.3 Thermal Properties of Materials 1 Candidates should be able to : Define and apply the concept of specific heat capacity. Select and apply the equation : E = mcδθ The MASS (m) of

More information

Define the notations you are using properly. Present your arguments in details. Good luck!

Define the notations you are using properly. Present your arguments in details. Good luck! Umeå Universitet, Fysik Vitaly Bychkov Prov i fysik, Thermodynamics, 0-0-4, kl 9.00-5.00 jälpmedel: Students may use any book(s) including the textbook Thermal physics. Minor notes in the books are also

More information

LAB 15: HEAT ENGINES AND

LAB 15: HEAT ENGINES AND 251 Name Date Partners LAB 15: HEAT ENGINES AND THE FIRST LAW OF THERMODYNAMICS... the quantity of heat produced by the friction of bodies, whether solid or liquid, is always proportional to the quantity

More information

Characteristics of Evaporators

Characteristics of Evaporators Characteristics of Evaporators Roger D. Holder, CM, MSME 10-28-2003 Heat or Energy In this paper, we will discuss the characteristics of an evaporator coil. The variance of the operational condenses of

More information

Total Heat Versus Sensible Heat Evaporator Selection Methods & Application

Total Heat Versus Sensible Heat Evaporator Selection Methods & Application Total Heat Versus Sensible Heat Evaporator Selection Methods & Application Scope The purpose of this paper is to provide specifying engineers, purchasers and users of evaporators in industrial refrigeration

More information

SAMPLE CHAPTERS UNESCO EOLSS

SAMPLE CHAPTERS UNESCO EOLSS STEAM TURBINE OPERATIONAL ASPECTS R.A. Chaplin Department of Chemical Engineering, University of New Brunswick, Canada Keywords: Steam Turbines, Operation, Supersaturation, Moisture, Back Pressure, Governing

More information

The first law: transformation of energy into heat and work. Chemical reactions can be used to provide heat and for doing work.

The first law: transformation of energy into heat and work. Chemical reactions can be used to provide heat and for doing work. The first law: transformation of energy into heat and work Chemical reactions can be used to provide heat and for doing work. Compare fuel value of different compounds. What drives these reactions to proceed

More information

Percent per Degree Rule of Thumb for Refrigeration Cycle Improvement

Percent per Degree Rule of Thumb for Refrigeration Cycle Improvement 7 Percent per Degree Rule of Thumb for Refrigeration Cycle Improvement Steve Doty, PE, CEM sdoty@csu.org ABSTRACT A value of 1-1.5% power reduction per degree Fahrenheit (F) has been used successfully

More information

QUESTIONS THERMODYNAMICS PRACTICE PROBLEMS FOR NON-TECHNICAL MAJORS. Thermodynamic Properties

QUESTIONS THERMODYNAMICS PRACTICE PROBLEMS FOR NON-TECHNICAL MAJORS. Thermodynamic Properties QUESTIONS THERMODYNAMICS PRACTICE PROBLEMS FOR NON-TECHNICAL MAJORS Thermodynamic Properties 1. If an object has a weight of 10 lbf on the moon, what would the same object weigh on Jupiter? ft ft -ft g

More information

Phase Diagram of tert-butyl Alcohol

Phase Diagram of tert-butyl Alcohol Phase Diagram of tert-butyl Alcohol Bill Ponder Department of Chemistry Collin College Phase diagrams are plots illustrating the relationship of temperature and pressure relative to the phase (or state

More information

SIMULATION OF THERMODYNAMIC ANALYSIS OF CASCADE REFRIGERATION SYSTEM WITH ALTERNATIVE REFRIGERANTS

SIMULATION OF THERMODYNAMIC ANALYSIS OF CASCADE REFRIGERATION SYSTEM WITH ALTERNATIVE REFRIGERANTS INTERNATIONAL JOURNAL OF MECHANICAL ENGINEERING AND TECHNOLOGY (IJMET) International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 6340(Print), ISSN 0976 6340 (Print) ISSN 0976 6359

More information

Calorimetry: Heat of Vaporization

Calorimetry: Heat of Vaporization Calorimetry: Heat of Vaporization OBJECTIVES INTRODUCTION - Learn what is meant by the heat of vaporization of a liquid or solid. - Discuss the connection between heat of vaporization and intermolecular

More information

Problem Set 4 Solutions

Problem Set 4 Solutions Chemistry 360 Dr Jean M Standard Problem Set 4 Solutions 1 Two moles of an ideal gas are compressed isothermally and reversibly at 98 K from 1 atm to 00 atm Calculate q, w, ΔU, and ΔH For an isothermal

More information

DRAFT. Appendix C.2 - Air Conditioning Thermodynamics 1

DRAFT. Appendix C.2 - Air Conditioning Thermodynamics 1 Appendix C.2 - Air Conditioning Thermodynamics 1 To aid in discussing the alternative technologies, it is helpful to have a basic description of how air conditioning systems work. Heat normally flows from

More information

Chapter 10: Refrigeration Cycles

Chapter 10: Refrigeration Cycles Capter 10: efrigeration Cycles Te vapor compression refrigeration cycle is a common metod for transferring eat from a low temperature to a ig temperature. Te above figure sows te objectives of refrigerators

More information

High Pressure Control

High Pressure Control Energy savings in commercial refrigeration equipment : High Pressure Control July 2011/White paper by Christophe Borlein AFF and IIF-IIR member Make the most of your energy Summary Executive summary I

More information

Heat. Investigating the function of the expansion valve of the heat pump. LD Physics Leaflets P2.6.3.2. Thermodynamic cycle Heat pump

Heat. Investigating the function of the expansion valve of the heat pump. LD Physics Leaflets P2.6.3.2. Thermodynamic cycle Heat pump Heat Thermodynamic cycle Heat pump LD Physics Leaflets P2.6.3.2 Investigating the function of the expansion valve of the heat pump Objects of the experiment g To study the operational components of the

More information

Problem Set 1 3.20 MIT Professor Gerbrand Ceder Fall 2003

Problem Set 1 3.20 MIT Professor Gerbrand Ceder Fall 2003 LEVEL 1 PROBLEMS Problem Set 1 3.0 MIT Professor Gerbrand Ceder Fall 003 Problem 1.1 The internal energy per kg for a certain gas is given by U = 0. 17 T + C where U is in kj/kg, T is in Kelvin, and C

More information

Vaporization of Liquid Nitrogen

Vaporization of Liquid Nitrogen Vaporization of Liquid Nitrogen Goals and Introduction As a system exchanges thermal energy with its surroundings, the temperature of the system will usually increase or decrease, depending on the direction

More information

Chapter 3.4: HVAC & Refrigeration System

Chapter 3.4: HVAC & Refrigeration System Chapter 3.4: HVAC & Refrigeration System Part I: Objective type questions and answers 1. One ton of refrigeration (TR) is equal to. a) Kcal/h b) 3.51 kw c) 120oo BTU/h d) all 2. The driving force for refrigeration

More information

ES-7A Thermodynamics HW 1: 2-30, 32, 52, 75, 121, 125; 3-18, 24, 29, 88 Spring 2003 Page 1 of 6

ES-7A Thermodynamics HW 1: 2-30, 32, 52, 75, 121, 125; 3-18, 24, 29, 88 Spring 2003 Page 1 of 6 Spring 2003 Page 1 of 6 2-30 Steam Tables Given: Property table for H 2 O Find: Complete the table. T ( C) P (kpa) h (kj/kg) x phase description a) 120.23 200 2046.03 0.7 saturated mixture b) 140 361.3

More information

Energy Analysis and Comparison of Advanced Vapour Compression Heat Pump Arrangements

Energy Analysis and Comparison of Advanced Vapour Compression Heat Pump Arrangements Energy Analysis and Comparison of Advanced Vapour Compression Heat Pump Arrangements Stuart Self 1, Marc Rosen 1, and Bale Reddy 1 1 University of Ontario Institute of Technology, Oshawa, Ontario Abstract

More information

The Fundamentals of Thermoelectrics

The Fundamentals of Thermoelectrics The Fundamentals of Thermoelectrics A bachelor s laboratory practical Contents 1 An introduction to thermoelectrics 1 2 The thermocouple 4 3 The Peltier device 5 3.1 n- and p-type Peltier elements..................

More information

Dynamic Process Modeling. Process Dynamics and Control

Dynamic Process Modeling. Process Dynamics and Control Dynamic Process Modeling Process Dynamics and Control 1 Description of process dynamics Classes of models What do we need for control? Modeling for control Mechanical Systems Modeling Electrical circuits

More information

Testing methods applicable to refrigeration components and systems

Testing methods applicable to refrigeration components and systems Testing methods applicable to refrigeration components and systems Sylvain Quoilin (1)*, Cristian Cuevas (2), Vladut Teodorese (1), Vincent Lemort (1), Jules Hannay (1) and Jean Lebrun (1) (1) University

More information

Chapter 6 The first law and reversibility

Chapter 6 The first law and reversibility Chapter 6 The first law and reversibility 6.1 The first law for processes in closed systems We have discussed the properties of equilibrium states and the relationship between the thermodynamic parameters

More information

Ambient Energy Fraction of a Heat Pump

Ambient Energy Fraction of a Heat Pump Ambient Energy Fraction of a Heat Pump u Aye, R. J. Fuller and.. S. Charters International Technologies Centre (IDTC) Department of Civil and Environmental Engineering The University of Melbourne Vic 3010

More information

Chapter 2 P-H Diagram Refrigeration Cycle Analysis & Refrigerant Flow Diagram

Chapter 2 P-H Diagram Refrigeration Cycle Analysis & Refrigerant Flow Diagram Chapter 2 P-H Diagram Refrigeration Cycle Analysis & Refrigerant Flow Diagram Copy Right By: Thomas T.S. Wan 温 到 祥 著 Sept. 3, 2008 All rights reserved Industrial refrigeration system design starts from

More information

Experiment 6 ~ Joule Heating of a Resistor

Experiment 6 ~ Joule Heating of a Resistor Experiment 6 ~ Joule Heating of a Resistor Introduction: The power P absorbed in an electrical resistor of resistance R, current I, and voltage V is given by P = I 2 R = V 2 /R = VI. Despite the fact that

More information

AIRAH Refrigeration (in HVAC) Back to Basics. For the First Time

AIRAH Refrigeration (in HVAC) Back to Basics. For the First Time AIRAH Refrigeration (in HVAC) Back to Basics For the First Time Terms of Reference What this session is NOT about Detailed Refrigeration Design Detailed analysis of various Refrigants properties Comparison

More information

Technical Thermodynamics

Technical Thermodynamics Technical Thermodynamics Chapter 2: Basic ideas and some definitions Prof. Dr.-Ing. habil. Egon Hassel University of Rostock, Germany Faculty of Mechanical Engineering and Ship Building Institute of Technical

More information

Warm medium, T H T T H T L. s Cold medium, T L

Warm medium, T H T T H T L. s Cold medium, T L Refrigeration Cycle Heat flows in direction of decreasing temperature, i.e., from ig-temperature to low temperature regions. Te transfer of eat from a low-temperature to ig-temperature requires a refrigerator

More information

ME 201 Thermodynamics

ME 201 Thermodynamics ME 0 Thermodynamics Second Law Practice Problems. Ideally, which fluid can do more work: air at 600 psia and 600 F or steam at 600 psia and 600 F The maximum work a substance can do is given by its availablity.

More information

OPTIMAL DESIGN AND OPERATION OF HELIUM REFRIGERATION SYSTEMS *

OPTIMAL DESIGN AND OPERATION OF HELIUM REFRIGERATION SYSTEMS * OPTIMAL DESIGN AND OPERATION OF HELIUM REFRIGERATION SYSTEMS * Abstract Helium refrigerators are of keen interest to present and future particle physics programs utilizing superconducting magnet or radio

More information

Kinetic Theory & Ideal Gas

Kinetic Theory & Ideal Gas 1 of 6 Thermodynamics Summer 2006 Kinetic Theory & Ideal Gas The study of thermodynamics usually starts with the concepts of temperature and heat, and most people feel that the temperature of an object

More information

Experiment #4, Ohmic Heat

Experiment #4, Ohmic Heat Experiment #4, Ohmic Heat 1 Purpose Physics 18 - Fall 013 - Experiment #4 1 1. To demonstrate the conversion of the electric energy into heat.. To demonstrate that the rate of heat generation in an electrical

More information

Swissmetro travels at high speeds through a tunnel at low pressure. It will therefore undergo friction that can be due to:

Swissmetro travels at high speeds through a tunnel at low pressure. It will therefore undergo friction that can be due to: I. OBJECTIVE OF THE EXPERIMENT. Swissmetro travels at high speeds through a tunnel at low pressure. It will therefore undergo friction that can be due to: 1) Viscosity of gas (cf. "Viscosity of gas" experiment)

More information

COMMERCIAL HVAC EQUIPMENT. Condensers and Cooling Towers

COMMERCIAL HVAC EQUIPMENT. Condensers and Cooling Towers COMMERCIAL HVAC EQUIPMENT Condensers and Cooling Towers Technical Development Programs (TDP) are modules of technical training on HVAC theory, system design, equipment selection and application topics.

More information