hello mohd,

• Maths : B S Grewal
• Theory of Machines : S S Rattan. For concepts : David Myszka (Machines and Mechanisms : Applied Kinematic Analysis)
• Machine Design : V B Bhandari, For concepts : R L Norton. For more solved problems : Schaum Series
• Thermal Engg / Thermodynamics: P K Nag , For concepts : Yunus A. Cengel (Fundamentals of Thermal and Fluid Sciences)
• Fluid Mechanics : Som & Biswas. For concepts : Yunus A. Cengel (Fundamentals of Thermal and Fluid Sciences). For more solved problems : TMH Sigma Series
• Operations Research : N D Vohra (Quantitative Techniques)
• Heat Transfer : R K Rajput. For concepts : Yunus A. Cengel (Heat Transfer : A Practical Approach)
• Refrigeration and AC : R K Rajput. For concepts : Yunus A. Cengel (Fundamentals of Thermal and Fluid Sciences)
• Industrial Engg. : O P Khanna
• Engg. Mechanics : R S Khurmi, Timoshenko and Young
• Strength of Material : Abdul Mubeen (Mechanics of Solids). For more concepts : Timoshenko and Gere (Mechanics of Materials). You may also refer to Beer and Johnson