相对速率，相对速度...

The spray quality is improved when the relative speed and length of indent chamber increase.随著缩进长度增大,雾化质量明显变好.And the relative speed value is less than 2 % by the engine speed regulator.和相对速度值小于2%的发动机转速调节....

relative speed的音标：relative speed的英式发音音标为：['relətiv spi:d]relative speed的美式发音音标为：['rɛlətɪv spid]...