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Engineering mechanics
82
BOOKREVmWS
transfer matrix of a disk for synchronous whirl is devel. oped in Chapter 6, including that for an overhung rotor. Chapters 7 and 8 deal with fluid film bearings and their effect on the dynamic behavior of rotors. The essential characteristics of steady state behavior are presented without formal solution to the governing differential equations. Stiffness and damping coefficients are presented for reference. Chapter 8 deals primarily with asymmetric and cross-coupled spring co¢fficients of a hydrodynamic bearing and the resultant effect on the out-of-balance response of a Jeffcot rotor. Bearing damping is next considered in detail. The chapter is concluded with the development of the general transfer matrix for the determination of the out-of-balance response. Instability phenomena associated with rotor bending and torsional vibrations are covered in Chapters 9, 10, and 11. In Chapter 9, a solution to Mathieu's equation is presented as of particular importance for stability analysis of a shaft having two principal axes. Disk unbalance and gravity effects are also considered. Instabilities due to oil film forces and internal shaft hysteresis are dealt with in Chapter 10. Simple design charts for threshold instability are presented for Jeffcot models. Chapter 11 is devoted to instability in torsional vibration due to variable stiffness and intertia. A reciprocating engine with heavy piston is included as a system with variable intertia for analysis. Chapters 12 and 13 are devoted to balancingand in-service condition monitoring by vibration measurements. The techniques of modal balancing and influence coefficients outlined in Chapter 12 are well-presented and illustrated by example. In Chapter 13, different vibration generating mechanisms arc discussed that help in identifying the source of trouble. International standards for quality judgement of condition monitoring are presented, and typical case studies involving failures arc discussed. The author has manned to compile in one text a subject area that from a practical standpoint is scattered throughout journals and government and industrial reports. This in itself makes the book an excellent addition to the tochnical literature. There are some minor distractions, such as poor printing quality of a time derivative, occasional omission of adjectives, unrefined figures, and loose binding. In spite of these, the book is very readable and well organized. There arc two perceived difficulties with the book: 1. Most solutions to examples are obtained utilizing computer programs of the author that are not included with the text, creating obvious difficulties for the student and the instructor. 2. With the exception of Chapter 13, the majority of references included at the end of each chapter are more than l0 years old, leading one to question the timeliness of the book. Perhaps future editions will address these problems and lend improvement to a well-written and useful text.
cipline, Engineering Mechanics is a treatise on the application of dynamics to the design of machinery and mechanisms, The first two chapters contain a detailed presentation of the basic vectorial nature of forces and displacements. Chapter 1 is devoted to planar kinematics and examples of basic linkage mechanisms are used to illustrate the theoretical developments. In contrast to this, Chapter 2 is dedicated to planar statics and it includes treatment of such standard topics as equilibrium of coplanar forces, friction and structures. Chapter 3 focusses on spatial kinematics and statics. The scalar and vector products are introduced, and the results applied to some physical systems in order to determine angular velocities and moments of forces. The principle of virtual work is briefly discussed in Chapter 4, which only comprises six pages. Chapter 5 represents the beginning of a four-chapter sequence in which the material is developed from differentiation of vector quantities through the dynamics of single particles and multiparticle systems, to rigid body dynamics. Having established the fundamentals in the previous chapters, these four chapters represent the main thrust of the text from a theoretical standpoint since the final chapter of the book demonstrates how these theories are employed in engineering practice. Chapter 5 begins with vector differentiation, which provides the basis for a study of single particle kinematics relative to cartesian, cylinderical polar and curvilinear coordinates. Moving reference frames arc also treated. The final pages of the chapter demonstrate how the theoretical developments presented earlier are applied to linkages and cam-follower systems. Having established the necessary kinematics, the subsequent chapter is devoted to single particle dynamics. Newton's laws are developed prior to introducing momentum and energy. The chapter concludes with a number of examples analyzing satellite motions and also several types of pendulum. Chapter 7 extends the theories of the previous chapter to multiparticle systems in a logical manner. Rigid body dynamics is presented in Chapter 8. This portion of the book begins with a section on rotor balancing and continues with kinetic energy, and the concepts of momentum and moment of momentum. Moving frames of reference are discussed before the chapter concludes with an exposition on inertia forces in planar mechanisms using d'Alembert's principle. Chapter 9 contains a very brief, five-page discussion on fluid particle streams. The final chapter is devoted to power transmission between parallel shafts. This is an attempt at bringing together all of the material developed in the preceding chapters and collectively applying it to specific engineering problems. Clutches, belt drives, gear trains and linkage mechanisms are considered. This book covers all of the basic engineeringmechanics needed by a student prior to him advancing to more speDR. ROBERTO. CASE cialized courses in vibration and control theory, kineFlorida Atlantic University matics and dynamics of machinery, and the theory of Dept. of Mechanical Engineering structures. Generally, there are clear comprehensible exBoca Raton, FL 33431 U.S.A. planations of the subject material with the author emphasizing the relationships between theoretical principles and practical applications. E n g i m m ' i ~ Meeimnies (first edition) by J. M. Prentis. Oxford University Press, Oxford, England, 1979, 258p. BRIANS. THOMPSON Associate Professor While the title of this book can be interpreted in a number Michigan State University of different ways, depending upon one's engineering dis- East Lansing, MI 48824 U.S.A.
BOOKREVmWS
transfer matrix of a disk for synchronous whirl is devel. oped in Chapter 6, including that for an overhung rotor. Chapters 7 and 8 deal with fluid film bearings and their effect on the dynamic behavior of rotors. The essential characteristics of steady state behavior are presented without formal solution to the governing differential equations. Stiffness and damping coefficients are presented for reference. Chapter 8 deals primarily with asymmetric and cross-coupled spring co¢fficients of a hydrodynamic bearing and the resultant effect on the out-of-balance response of a Jeffcot rotor. Bearing damping is next considered in detail. The chapter is concluded with the development of the general transfer matrix for the determination of the out-of-balance response. Instability phenomena associated with rotor bending and torsional vibrations are covered in Chapters 9, 10, and 11. In Chapter 9, a solution to Mathieu's equation is presented as of particular importance for stability analysis of a shaft having two principal axes. Disk unbalance and gravity effects are also considered. Instabilities due to oil film forces and internal shaft hysteresis are dealt with in Chapter 10. Simple design charts for threshold instability are presented for Jeffcot models. Chapter 11 is devoted to instability in torsional vibration due to variable stiffness and intertia. A reciprocating engine with heavy piston is included as a system with variable intertia for analysis. Chapters 12 and 13 are devoted to balancingand in-service condition monitoring by vibration measurements. The techniques of modal balancing and influence coefficients outlined in Chapter 12 are well-presented and illustrated by example. In Chapter 13, different vibration generating mechanisms arc discussed that help in identifying the source of trouble. International standards for quality judgement of condition monitoring are presented, and typical case studies involving failures arc discussed. The author has manned to compile in one text a subject area that from a practical standpoint is scattered throughout journals and government and industrial reports. This in itself makes the book an excellent addition to the tochnical literature. There are some minor distractions, such as poor printing quality of a time derivative, occasional omission of adjectives, unrefined figures, and loose binding. In spite of these, the book is very readable and well organized. There arc two perceived difficulties with the book: 1. Most solutions to examples are obtained utilizing computer programs of the author that are not included with the text, creating obvious difficulties for the student and the instructor. 2. With the exception of Chapter 13, the majority of references included at the end of each chapter are more than l0 years old, leading one to question the timeliness of the book. Perhaps future editions will address these problems and lend improvement to a well-written and useful text.
cipline, Engineering Mechanics is a treatise on the application of dynamics to the design of machinery and mechanisms, The first two chapters contain a detailed presentation of the basic vectorial nature of forces and displacements. Chapter 1 is devoted to planar kinematics and examples of basic linkage mechanisms are used to illustrate the theoretical developments. In contrast to this, Chapter 2 is dedicated to planar statics and it includes treatment of such standard topics as equilibrium of coplanar forces, friction and structures. Chapter 3 focusses on spatial kinematics and statics. The scalar and vector products are introduced, and the results applied to some physical systems in order to determine angular velocities and moments of forces. The principle of virtual work is briefly discussed in Chapter 4, which only comprises six pages. Chapter 5 represents the beginning of a four-chapter sequence in which the material is developed from differentiation of vector quantities through the dynamics of single particles and multiparticle systems, to rigid body dynamics. Having established the fundamentals in the previous chapters, these four chapters represent the main thrust of the text from a theoretical standpoint since the final chapter of the book demonstrates how these theories are employed in engineering practice. Chapter 5 begins with vector differentiation, which provides the basis for a study of single particle kinematics relative to cartesian, cylinderical polar and curvilinear coordinates. Moving reference frames arc also treated. The final pages of the chapter demonstrate how the theoretical developments presented earlier are applied to linkages and cam-follower systems. Having established the necessary kinematics, the subsequent chapter is devoted to single particle dynamics. Newton's laws are developed prior to introducing momentum and energy. The chapter concludes with a number of examples analyzing satellite motions and also several types of pendulum. Chapter 7 extends the theories of the previous chapter to multiparticle systems in a logical manner. Rigid body dynamics is presented in Chapter 8. This portion of the book begins with a section on rotor balancing and continues with kinetic energy, and the concepts of momentum and moment of momentum. Moving frames of reference are discussed before the chapter concludes with an exposition on inertia forces in planar mechanisms using d'Alembert's principle. Chapter 9 contains a very brief, five-page discussion on fluid particle streams. The final chapter is devoted to power transmission between parallel shafts. This is an attempt at bringing together all of the material developed in the preceding chapters and collectively applying it to specific engineering problems. Clutches, belt drives, gear trains and linkage mechanisms are considered. This book covers all of the basic engineeringmechanics needed by a student prior to him advancing to more speDR. ROBERTO. CASE cialized courses in vibration and control theory, kineFlorida Atlantic University matics and dynamics of machinery, and the theory of Dept. of Mechanical Engineering structures. Generally, there are clear comprehensible exBoca Raton, FL 33431 U.S.A. planations of the subject material with the author emphasizing the relationships between theoretical principles and practical applications. E n g i m m ' i ~ Meeimnies (first edition) by J. M. Prentis. Oxford University Press, Oxford, England, 1979, 258p. BRIANS. THOMPSON Associate Professor While the title of this book can be interpreted in a number Michigan State University of different ways, depending upon one's engineering dis- East Lansing, MI 48824 U.S.A.