STEAM-ENGINE AND PROFESSOR OF MECHANISM AND APPLIED MECHANICS IN THE UNIVERSITY OF CAMBRIDGE. CAMBRIDGE: AT THE UNIVERSITY PRESS.

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THE STEAM-ENGINE AND OTHEE HEAT-ENGINES BY J. A. EWING, M.A., B.Sc, F.E.S., M.INST.C.E., PROFESSOR OF MECHANISM AND APPLIED MECHANICS IN THE UNIVERSITY OF CAMBRIDGE.

1 THE STEAM-ENGINE AND OTHEE HEAT-ENGINES BY J. A. EWING, M.A., B.Sc, F.E.S., M.INST.C.E., PROFESSOR OF MECHANISM AND APPLIED MECHANICS IN THE UNIVERSITY OF CAMBRIDGE. CAMBRIDGE: AT THE UNIVERSITY PRESS [All Bights reserved.]

CONTENTS. I. THE EARLY HISTORY OF THE STEAM-ENGINE. AKT. 1. Heat-Engines in general 1 2. Hero of Alexandria 2 3. Delia Porta and De Caus 3 4. Branca's Steam Turbine 4 5. Marquis of Worcester 4 6.

2 CONTENTS. I. THE EARLY HISTORY OF THE STEAM-ENGINE. AKT. 1. Heat-Engines in general 1 2. Hero of Alexandria 2 3. Delia Porta and De Caus 3 4. Branca's Steam Turbine 4 5. Marquis of Worcester 4 6. Savery 5 7. Gunpowder Engines 7 8. Papin 7 9. Newcomen's "Atmospheric" Engine James Watt Watt's pumping-engine of Watt's narrative of his invention Development of Watt's Engine: the rotative type Further improvements by Watt Non-condensing Steam-Engines Use of comparatively high-pressure steam Compound Engines. Hornblower and Woolf The Cornish Pumping Engine Revival of the Compound Engine Application to locomotives Application to steamboats Development of the Theory of Heat-Engines II. ELEMENTARY THEORY OF HEAT-ENGINES. 23. Laws of Thermodynamics. The First Law The Second Law of Thermodynamics The Working Substance in a Heat-Engine 35

viii CONTENTS. AKT. 26. Graphic Representation of Work done in the changes of volume of a fluid 36 27. Cycle of operations of the working substance.... 37 28.

3 viii CONTENTS. AKT. 26. Graphic Representation of Work done in the changes of volume of a fluid Cycle of operations of the working substance Engine using a perfect gas as working substance Laws of the permanent gases. Boyle's law Charles's law Absolute temperature Connection between Pressure, Volume, and Temperature in a gas The specific heat of a gas The Internal energy of a gas Relation between the two Specific Heats Values of the constants for Air Work done by an expanding fluid Adiabatic Expansion Change of temperature in the adiabatic expansion of a gas Isothermal Expansion Carnot's Cycle of operations Efficiency in Carnot's Cycle Carnot's cycle reversed Reversible engine Carnot's Principle Reversibility the criterion of perfection in a heat-engine Efficiency of a perfect heat-engine Summary of the argument Conditions of maximum efficiency Conditions of reversibility Perfect Engine using Regenerator Stirling's Regenerative Air-Engine 60 III. PROPERTIES OF STEAM AND ELEMENTARY THEORY OF THE STEAM-ENGINE. 53. Formation of steam under constant pressure Saturated and superheated steam Relation of pressure and temperature in saturated steam Relation of pressure and volume in saturated steam Supply of heat in the formation of steam under constant pressure Latent Heat of Steam Total heat of steam Internal energy of steam Formation of steam otherwise than under constant pressure Wet steam Superheated steam Isothermal Lines for Steam 71

CONTENTS. IX 65. Adiabatio Lines for Steam 72 66. Formula connecting pressure with volume in the adiabatic expansion of steam 74 67. Carnot's cycle with steam for working substance... 75 68.

4 CONTENTS. IX 65. Adiabatio Lines for Steam Formula connecting pressure with volume in the adiabatic expansion of steam Carnot's cycle with steam for working substance Efficiency of a perfect steam-engine. Limits of temperature Efficiency of an engine using steam non-expansively Engine with separate organs How nearly may the process in a steam-engine be reversible? 81 IV. FUETHER POINTS IN THE THEORY OF HEAT-ENGINES. 72. Rankine's statement of the Second Law Absolute Temperature: Lord Kelvin's scale Calculation of the Density of Saturated Steam Extension of the above result to other changes of physical state Drying of steam by throttling or wire-drawing Engine receiving heat at various temperatures Application to the case of a steam-engine working without compression, but with complete adiabatic expansion Extension to the case of steam not initially dry Derivation of the adiabatic equation from this result Entropy Entropy of Steam : Derivation of the Adiabatic Equation Entropy-Temperature Diagrams Entropy-Temperature Diagram for Steam : application to ideal steam-engine working without compression but with complete expansion Application of the entropy-temperature diagram to the case of superheated steam Values of the Entropy of Water and Steam Entropy-temperature diagram for Steam used non-expansively Incomplete expansion Entropy-temperature diagrams in engines using a Regenerator Joule's Air-Engine Reversal of the cycle in heat-engines : Refrigerating Machines or Heat-Pumps 1]8 92. Coefficient of Performance of Refrigerating Machines Reversed Joule Engine : the Bell-Coleman refrigerating machine The Reversed Heat-Engine as a Warming Machine Heat-Engines employing more than one working substance : Steam and Ether Engines Transmission of Power by Compressed Air

X CONTENTS. - V. ACTUAL BEHAVIOUE OP STEAM IN THE CYLINDER. AET. 97. Comparison of actual and ideal indicator diagrams... 131 98. Wire-drawing during Admission and Exhaust.... 132 99.

5 X CONTENTS. - V. ACTUAL BEHAVIOUE OP STEAM IN THE CYLINDER. AET. 97. Comparison of actual and ideal indicator diagrams Wire-drawing during Admission and Exhaust Clearance Compression Cushion Steam and Cylinder Feed Influence of the Cylinder Walls. Condensation and Re-evaporation in the Cylinder Ee-evaporation continued during the exhaust Wetness of the working steam Graphic Representation, on the Indicator Diagram, of the water present during expansion Use of the Entropy-Temperature diagram in exhibiting the behaviour of steam during expansion and the exchanges of heat between it and the cylinder walls Thermodynamic Loss due to Initial Condensation Action of a Steam-jacket Influence of Speed, Size, and Ratio of Expansion Results of Experiments with various ratios of Expansion Advantage of high speed Experiments on the value of the Steam-jacket Superheating Advantage of Compound Expansion Summary of Sources of Loss Methods of stating the performance of Steam-Engines Efficiency of boiler and furnace. "Duty" Results of Trials : Non-Condensing Engines Results of Trials : Condensing Engines Mechanical Efficiency of the Engine Curve of Expansion to be assumed in estimating the probable indicated horse-power of steam-engines VI. THE TESTING OF STEAM-ENGINES The Indicator Conditions of accurate working Directions for taking Indicator Diagrams Calculation of the Indicated Horse-Power Examples of Indicator Diagrams Thermodynamic Tests. Measurement of the Supply of Steam by means of the Feed 179

CONTENTS. xi ЛЕТ. РАНЕ 128. Measurement of the Supply of Steam by means of the Condenaed Water 181 129. Measurement of Jacket steam. 182 130. Comparison of Feed-water with Discharged Water...182 131.

6 CONTENTS. xi ЛЕТ. РАНЕ 128. Measurement of the Supply of Steam by means of the Condenaed Water Measurement of Jacket steam Comparison of Feed-water with Discharged Water Estimation of Heat supplied. Measurement of Dryness of the Steam by the "Barrel" Calorimeter Barrus Calorimeter Peabody Throttling Calorimeter Measurement of Heat rejected by an Engine Example of an Engine Trial Wetness of the steam during expansion Transfer of Heat between the Steam and the Metal. Hirn's Analysis Tests of mechanical efficiency. Measurement of Brake Horsepower Trials of an engine under various amounts of load VII. COMPOUND EXPANSION Woolf Engines Receiver engine Drop in the Receiver. Compound diagrams Adjustment of the division of work between the cylinders, and of the drop. Graphic method Algebraic Method Ratio of Cylinder Volumes Advantage of Compound Expansion in the economical use of High-Pressure Steam Mechanical advantage of Compound Expansion. Uniformity of Effort in a Compound Engine Examples of Indicator Diagrams from Compound Engines Combination of the Indicator Diagrams in Compound Expansion 209 VIII. VALVES AND VALVE-GEAKS The Slide-Valve Lap, Lead, and Angular Advance Graphic method of examining the distribution of steam given by a slide-valve 219

XU CONTENTS. ART. 153. Inequality of the distribution on the two sides of the piston. 222 154. Zeuner's Valve Diagram 225 155. Oval Diagram 228 156. Harmonic Diagram 229 157. Reversing Gear.

7 XU CONTENTS. ART Inequality of the distribution on the two sides of the piston Zeuner's Valve Diagram Oval Diagram Harmonic Diagram Reversing Gear. The Link-motion Graphic Solution of the Link-motion Equivalent eccentric Eadial Gears Separate expansion-valves Meyer's Expansion-valve Forms of slide-valves. Double-ported valve. Trick valve Belief Frames Piston Valves Rocking slide-valve Double-beat valve. The Cornish cataract 250 IX. GOVERNING Methods of regulating the work done in a Steam-engine Automatic regulation by centrifugal speed governors. Watt's Conical Pendulum Governor Loaded Governors Controlling Force Condition of Equilibrium Condition of Stability Equilibrium of the Conical Pendulum Governor. Height of the Governor Equilibrium of Loaded Governor Sensibility in a Governor. Isochronism Isochronism in the Gravity Governor. Parabolic Governor Approximate Isochronism in Pendulum Governors Governors with spring control. Adjustment of sensitiveness Determination of the Controlling Force Influence of Friction. Power of the Governor Curves of Controlling Force Hunting Governor with horizontal axis Throttle-valve and automatic expansion-gear Corliss and other Trip-gear Disengagement governors Eelay governors Differential or dynamometric governors Pump governors Governing marine engines 279

CONTENTS. ХШ X. AKT. THE WORK ON THE CRANK-SHAFT. 192. Fluctuations of Speed during any single revolution : function of the Fly-wheel 280 193. Diagram of crank-effort 280 194.

8 CONTENTS. ХШ X. AKT. THE WORK ON THE CRANK-SHAFT Fluctuations of Speed during any single revolution : function of the Fly-wheel Diagram of crank-effort Effect of Friction Effect of the inertia of the reciprocating pieces Inertia of the Connecting-rod Treatment of Inertia and Friction together Forms of Crank-Effort Diagrams Fluctuation of Speed in relation to the Energy of the Flywheel Reversal of thrust at the joints. Prevention of reversal of the thrust in single-acting engines Balancing 294 PÄQE XL THE PRODUCTION OP STEAM. BOILERS Heating Surface, in Boiler and Feed-water Heater Draught Sources of loss of Heat Chimney Draught Boilers for Stationary Engines. Cornish and Lancashire Types Boiler Mountings Multitubular Boilers Vertical Boilers Watertube Boilers Locomotive Boilers Marine Boilers Feeding boilers. The Injector Feed-water heaters Use of Zinc to prevent corrosion in boilers Methods of forcing draught Mechanical Stoking Liquid Fuel 322

XIV CONTENTS. ABT. XII. FORMS OF THE STEAM-ENGINE. 219. Terms used in classification 324 220. Beam-Engines 325 221. Direct-acting Horizontal and Vertical Engines.... 326 222.

9 XIV CONTENTS. ABT. XII. FORMS OF THE STEAM-ENGINE Terms used in classification Beam-Engines Direct-acting Horizontal and Vertical Engines Single-acting high speed Engines Pumping Engines The pulsometer Davey's safety motor Rotary Engines Steam Turbines Marine Engines Relation of power to weight in Marine Engines Locomotives Compound Locomotives Tramway and Road Locomotives 354 XIII. AIB, GAS AND OIL-ENGINES Air and Gas-engines with external or internal combustion Air-engine using Carnot's cycle External Combustion Air-engine with Regenerator: Stirling, Ericsson Modern Air-engines of the Stirling type Internal Combustion Air-engines Early Gas-engines The four-stroke cycle of Beau de Rochas and Otto The Otto Engine Other Gas-engines Action in the cylinder of the Otto Engine After-burning Performance of Gas-engines Ideal performance of an internal combustion engine Use of cheap gas Oil-engines 383 APPENDIX : ' TABLE OP PROPERTIES OP SATURATED STEAM INDEX 391

Noble Group of Institutions, Junagadh. Faculty of Engineering Department of Mechanical Engineering

Noble Group of Institutions, Junagadh. Faculty of Engineering Department of Mechanical Engineering Semester:1 st Subject: Elements of Mechanical Engineering (2110006) Faculty: Mr. Ishan Bhatt Year: 2017-18 Class: Comp. & IT Ele TUTORIAL 1 INTRODUCTION Q.1 Define: Force, Work, Pressure, Energy, Heat