Cooling air for a reciprocating engine can be obtained by means of

CLASSIFICATION OF MATERIALS:-PETREOS Natural stone, can take the form of blocks or tiles, or as granules. Ejmplo: marble, slate, sand. -ceramics and glass: they are made from baking clay, like tiles and bricks, or the function of minerals such as glass. -composite materials: they are products formed by mixing materials with different properties but easily distinguishable from each other. Ejmplos: asphalt which is a mixture of tar and gravel, and concrete is a mixture of cement, sand, gravel and water. "Metallic materials obtained from minerals, examples: aluminum, iron, or steel. -binding materials: they are powdered products which when mixed with water, undergo chemical transformations producing a hardening in air or under water, this process known as FRAGUADO.Ejemplos: cement and plaster. ELEMENTS OF CONSTRUCTION:-foundation: concrete, support the weight of the building. -structure: It consists of columns, beams and joists can be reinforced concrete or steel. -floors and ceilings: joists are placed on the ceramic vaults, which is capped with concrete and covered with ceramic tiles or wood, the roofs are covered with plaster or plaster.

- External walls: usually a double brick wall with uan camara interior can be filled with an insulating material such as fiberglass, polyurethane or expanded poliestilereno. -windows: glass used in windows, you must place a lintel to hold the bricks in the top of window opening. This is usually a reinforced concrete beam or an alignment of bricks vertically. -cover: a structural support steel or wood on which is superimposed a waterproof material fiber glass mixed with polyester and then covered with tile or slate. -Interior walls: brick can be made of prefabricated panels or plaster or wood. Echos are brick if you need to apply plaster to smooth the surface. PROPERTIES OF CONSTRUCTION MATERIALS:-density: means they are generally medium density, and are less heavy than some metals. -compressive strength: stone and ceramic materials are very resistant to compression in some cases more than steel such as pro glass.