A Packed Bed Reactor is a type of chemical reactor commonly used in industrial processes. It consists of a cylindrical vessel filled with solid catalyst particles, where reactants flow through the bed. The design allows for efficient contact between the gas or liquid reactants and the catalyst, facilitating chemical reactions. These reactors are widely used in applications such as catalytic converters in vehicles and petrochemical production. The packed bed configuration helps maintain a high surface area for reactions while ensuring good mass transfer. This makes them suitable for both exothermic and endothermic reactions in various industries.