The book “Thermal Engineering-II”, authored by Mr. S. Perumal, Dr. R. Jayaprakash, and others, provides an in-depth exploration of the principles and applications of thermal engineering concepts vital for mechanical engineering professionals and students. It serves as a resource for understanding the design, operation, and maintenance of thermal systems used in industries such as power generation, refrigeration, and air conditioning. This text begins with the study of steam nozzles, discussing types, properties, and applications, highlighting their role in controlling fluid flow in systems like turbines and injectors. It explores the fundamentals of boilers, including classifications, requirements, and operational efficiencies, providing insights into fire tube and water tube boilers, low and high-pressure systems, and their comparative benefits and applications. The section on steam turbines delves into classifications, compounding methods, velocity diagrams, and energy losses, emphasizing their significance in energy conversion. The book also addresses the principles of cogeneration and waste heat recovery, offering strategies for energy optimization through systems like block diagrams and heat recovery devices. In the domain of refrigeration and air conditioning, the text explores historical advancements and working principles of various systems, including vapor compression and absorption systems. It incorporates psychrometrics, cooling load calculations, and modern refrigeration methods like thermoelectric cooling, stressing the importance of efficiency and environmental impact. With an emphasis on real-world applications, the book includes solved examples, illustrations, and detailed analyses of advanced systems like Benson and La Mont boilers, alongside practical guidelines for designing and improving efficiency. It highlights modern advancements such as supercritical boilers and the use of economizers, air preheaters, and superheaters for enhanced performance. Overall, “Thermal Engineering-II” serves as a comprehensive guide, combining theoretical knowledge with practical insights to prepare readers for the challenges and innovations in thermal engineering.