Abstract: A fire pit comprising a body having a side wall structure. The body further comprises a base plate located adjacent a lower end portion of the side wall structure, and an opening defined by a perimeter of an upper end portion of the side wall structure. Together, the side wall structure and the base plate form a fire pit chamber. The lower end portion of the side walls and the base plate form a collection sump for collecting and retaining ash that is generated during use. The lower portion of two opposite side walls and and the base plate are tapered downwards towards the center of the base plate to facilitate collection of ash.

Abstract: An enhanced heat exchanger (10) consists of a tube (11) receiving heat from an external source. A fluid (F) to be heated flows through the free area created between the body (12, 12?), introduced inside the tube (11), and the tube itself. Both the tube (11) and the body (12, 12?) heat the fluid (F). The body transfers to the fluid the energy received by the tube (11) by all the lo three modes of heat transfer: conduction, convection and radiation.