Glossary of Compressed Air Terms :: E :: Glossary Index A B C D E F G H I J K L M N O P Q R S T U V W X Y Z Effective area The area (in sq inches) of the filter element that is exposed to the flow of air or fluid for effective filtering. Efficiency Ability of a filter to remove particle matter from an air stream. Measured by comparing concentrate of material upstream and downstream of the filter. Typical particulate sizes range from .3 micron to 50 micron. Efficiency compression Is the ratio of the theoretical work requirement to the actual work required to be performed on the gas for compression and delivery. Efficiency isothermal Is the ratio of the theoretical work calculated on an isothermal basis to the actual work transferred to the gas during compression. Efficiency mechanical Is the ratio of the thermodynamic work requirement in the cylinder to actual brake horsepower requirement. Efficiency polytropic Is the ratio of the polytropic compression energy transferred to the gas to the actual energy transferred to the gas. Efficiency volumetric Is the ratio of actual capacity to piston displacement, stated as a percentage. Ejector compressor A compressor belonging to the group of dynamic compressors. Element The medium or material that does the actual filtering or separating. May be paper, wire mesh, special cellulose, inorganic plastic, or a combination. Emulsibility The ability of a non-water-soluble fluid to form an emulsion with water. Emulsifier Additive that promotes the formation of a stable mixture, or emulsion, of oil and water. Common emulsifiers are: metallic soaps, certain animal and vegetable oils, and various polar compounds. Emulsion Intimate mixture of oil and water, generally of a milky or cloudy appearance. Emulsions may be of two types: oil-in water (where water is the continuous phase) and water-in-oil (where water is the discontinuous phase). End cap A ported or closed cover for the end of a filter element. Energy audit A survey that shows how much energy you use in your compressed air generation. It will help find ways to use energy more efficiently. Energy conservation Practices and measures that increase energy efficiency. Energy kinetic Is the energy a substance possesses by virtue of its motion or velocity. Used primarily in calculations for dynamic and ejector type compressors. Energy storage The ability to convert energy into other forms, such as heat or chemical reaction, so that it can be retrieved for later use. Also the development, design, construction and operation of devices for storing energy until needed. Technology includes devices such as compressed gas. Enthalpy Is the sum of the internal and external energies. Entrainment ratios Are used with ejectors to convert weight of gas and/or water vapor handled to or from equivalent air. Entropy Is a measure of the unavailability of energy in a substance. Environmental contaminant all material and energy present in and around an operating system, such as dust, air moisture, chemicals, and thermal energy. Evaporation The escape of water molecules from a liquid to the gas phase at the surface of a body of water. Evaporator The chamber located on suction side of cap tube, in which freon is evaporated to cause cooling in a refrigeration system. Exothermic A term used to describe a chemical process in which heat is released. For example, combustion is an exothermic process because heat is released. Expanders Turbines or engines in which gas expands, does work, and undergoes a drop in temperature. Glossary Index A B C D E F G H I J K L M N O P Q R S T U V W X Y Z