20、东风11机车逆流装置NL的作用？
["\u7b54\uff1a\u5728\u84c4\u7535\u6c60\u5145\u7535\u7535\u8def\u4e2d\u8bbe\u6709\u9006\u6d41\u88c5\u7f6eNL\uff0c\u5f53\u8f85\u52a9\u53d1\u7535\u673aQD\u7684\u7aef\u7535\u538b\u9ad8\u4e8e\u84c4\u7535\u6c60\u7535\u538b\u65f6\uff0cNL\u4e2d\u7684\u4e24\u4e2a\u5e76\u8054\u7684\u4e8c\u6781\u7ba1\u5747\u5904\u4e8e\u6b63\u5411\u5bfc\u901a\u72b6\u6001\uff0cQD\u7ecf2RD\u3001NL\u3001RC\u30011RD\u30013FL\u5411\u84c4\u7535\u6c60\u5145\u7535\u3002\u5982QD\u505c\u6b62\u53d1\u7535\u6216\u5176\u7aef\u7535\u538b\u4f4e\u4e8e\u84c4\u7535\u6c60\u7535\u538b\u65f6\uff0cNL\u4e2d\u7684\u4e8c\u6781\u7ba1\u5904\u4e8e\u53cd\u5411\u622a\u6b62\u72b6\u6001\uff0c\u8fd9\u79cd\u72b6\u6001\u53ef\u9632\u6b62\u84c4\u7535\u6c60\u7ecfNL\u653e\u7535\u3002\u5728QD\u505c\u6b62\u53d1\u7535\u7684\u77ac\u95f4\uff0c\u52a0\u5728\u4e8c\u6781\u7ba1\u4e0a\u7684\u53cd\u5411\u7535\u538b\u5f88\u9ad8\uff0c\u4e3a\u4e86\u9632\u6b62\u53cd\u5411\u51fb\u7a7fNL\u4e2d\u7684\u4e8c\u6781\u7ba1\uff0c\u5728\u9006\u6d41\u88c5\u7f6e\u4e2d\u91c7\u7528\u4e86\u963b\u5bb9\u4fdd\u62a4\u3002"]