方向的下流(顺流) parallel downflow rinse: 并行下流冲洗downflow: 往下流; 下降流; 下降气流; 向下流动; 溢流管downflow evaporator: 降膜蒸发器downflow filter: 下流式过滤器downflow operation: 下流操作下载手机词典可随时随地查词查翻译