数字计时器?    digital chronometer

数字式磁带记录器?    digital magnetic recorder

数字化?    digitalisation

稀释排气?    diluted exhaust

稀释?    dilution

算术平均值    dilution

稀释用空气?    dilution air

稀释系数?    dilution factor

稀释风道?    dilution ratio

取样探管?    dilution tunnel

机油量尺?    dipstick

直接喷射式柴油机?    direct injection engine

直接光线?    direct light ray

直接取样法?    direct sampling method

直接式气门驱动机构?    direct valve gear

直接冷却式活塞?    direct-cooled piston

主要力方向?    direction of principal force (PDOF)

旋转方向?    direction of rotation

排气量?    displacement

牵引叉销至车辆前端的距离?    distance between jaw and front end of towing vehicle

半挂车间隙半径    distance between jaw and front end of towing vehicle

牵引装置至车辆前端的距离?    distance between towing device and front end of towing vehicle

牵引叉销至车辆前端的距离    distance between towing device and front end of towing vehicle

牵引座前置距    distance of towing attachment

牵引装置牵距?    distance of towing attachment

失真指数?    distortion index

分配式燃油喷射泵?    distributor fuel injection pump

昼间换气损失?    diurnal breathing losses

分开式燃烧室?    divided combustion chamber

圆顶活塞?    dome head piston

门宽    door height

门高?    door height

门宽?    door width

车架有效长度    door width

多普勒效应法?    doppler effect method

剂量阀活塞?    dosage valve piston

双重或三重喉管?    double & triple venturi

双坡口油环?    double bevelled oil control ring

双挂式道路列车?    double road train

双层客车?    double-deck bus

下流式转化器?    down flow type converter

下行程?    down stroke