Shell and tube heat exchangers are a common type of heat exchanger used in various industries. Within this category, two primary designs stand out: floating head and U-tube. Each design has its own advantages and disadvantages, making it suitable for specific applications.

A natural draft air cooler typically consists of a tall, tower-like structure with a large number of finned tubes. The hot process fluid flows through the tubes, and the heat is transferred to the surrounding air. The heated air rises due to natural convection, drawing in cooler air from the surroundings.