Convergent exhaust duct --  duct used on fixed-wing aircraft; formed by tapering toward the rear of the duct.   Convex --  suction side of an airfoil.   Crossover tube --  duct carrying flame to the individual cylindrical liners of the can-annular combustion chamber. 
 

 
 
飛機發動機術語英文解釋（D）
 

Diffuser --  aft structural member of an engine. It receives high velocity air from the centrifugal impeller and decreases velocity and increases air pressure. In the combustor, a diffuser forms a divergent flow path for the exhaust gases.   Diffusion --  process by which gases intermingle as the result of their spontaneous movement caused by thermal agitation.   Directional references --  specific definitions of terms referring to gas turbine engines to identify front and rear, right and left, bottom and top.   Divergent area --  place where air flows from a smaller into a larger area.   Divergent exhaust duct --  used on helicopter. Device to diffuse the exhaust gases rearward and to eliminate thrust.   Drag parasite --  drag caused by any member or structure which does not contribute to lift, such as engine cowlings.   Drag profile --  friction resistance produced by a member moving through the air; in simple terms, the "stickness" of air against the surface of an airfoil.   Dry-cleaning solvent -- 
 

cleaning compound that maybe used for all metal parts.   Dry-sump engine --  one in which the oil is stored separate from the engine.   Dual compressor --  see centrifugal-flow, axial-flow compressor.   Duplex nozzle --  dual-orifice channel through which highly atomized and accurately shaped sprays of fuel go into the combustion chamber.   Dynamic load --  load on an aircraft due to a dynamic force. 
 

 
 
飛機發動機術語英文解釋（E）
 

Effective angle of attack --  that part of a given angle of attack that lies between the chord of an airfoil and a line representing the resultant velocity of the disturber airflow.   End play --  longitudinal back-and-forth play of a shaft.   Engine airflow path --  route of the airflow through the engine.   Engine oil pressure indicating system --  device that gives continuous readings of engine oil pump pressure in psi.   Engine oil temperature indicating system --  device electrically connected to the 28 VDC system which transmits temperature readings to the indicator in degrees centigrade.   Engine speed notation --  the capital letter N, which represents the rotational speed of the engine. When a number is placed after the N (as in "N1"), it indicates a specific system on the engine.   Engine stations --  specific locations on the engine designating temperature or pressure-measuring locations. For example, T3 means the third temperature pickup on the engine.