Heat exchangers are critical components in thermal systems used in power plants, chemical processing units, refrigeration systems, and manufacturing industries. Among various types, shell-and-tube heat exchangers are widely preferred due to their robust construction and adaptability to high-pressure and high-temperature applications. However, their thermal performance is strongly influenced by internal flow arrangements, particularly baffle design. Conventional segmental baffles improve heat transfer but also introduce significant pressure drop, increasing pumping power requirements. This study investigates the thermal and hydraulic performance of a shell-and-tube heat exchanger using modified baffle configurations. Mathematical modeling and experimental evaluation were employed to analyze heat transfer coefficient, effectiveness, pressure drop, and overall thermal efficiency. The results demonstrate that modified baffle arrangements enhance heat transfer while reducing flow resistance, offering improved thermal performance and energy efficiency.