This textbook on 'Prime Movers and Fluid Machines' is based on a course that is taught to Mechanical and Chemical engineering students in many niversities/institutes/colleges. This book deals with the study, design, and analysis of turbo-machinery. It covers a wide range of topics, viz. hydraulic turbines, pumps, compressors, steam nozzles, steam turbines, and gas turbines. There was a strong need to cover such a variety of topics in a single book, since different books by different authors use different notations. For users, it becomes difficult to follow different notations inrelated topics. A sincere attempt has been made to streamline the notations and terminologies followed in various turbo machines. Contents 1. Dimensional Analysis & Model Testing, 2. Hydraulic Turbines, 3. Reciprocating Pumps, 4. Centrifugal Pumps, 5. Reciprocating Compressors, 6. Centrifugal Compressors, 7. Axial Flow Compressors, 8. Steam Nozzles, 9. Steam Turbines, 10. Gas Turbines About the Author Manoj Kumar Soni is an Associate professor in the Mechanical Engineering department and coordinator of the Centre for Renewable Energy and Environment Development at Birla Institute of Technology and Science (BITS), Pilani. He is a B.E. (Mechanical), M.E. (Thermal Power Engineering), and Ph.D. in Energy Efficiency. He was a faculty at VNIT Nagpur before joining BITS Pilani in 2002 with a total of 27+ years of teaching and research experience. He has been teaching Prime Movers and Fluid Machines course at BITS Pilani for the last fourteen years. He is a Fellow of the Institution of Engineers and recipient of the prestigious Dr. Shirin Gadhia Sustainability Award 2019 from Eco Center ICNEER, Vadodara. He also received Stifterverband Scholarship from Institut fOr Werkzeugmaschinen and Fertigungstechnik, Technische Universitat, Braunschweig, Germany, in 2019 for visiting TU Braunschweig for one week for his research work. His research interest includes thermal engineering, renewable energy, and energy efficiency. He has published two books and over 50 articles in international journals and conferences of repute and filed one Indian and one patent in the USA.