浅析人为航向法消除磁罗经自差.doc

浅析“人为航向法”消除磁罗经自差

摘要  磁罗经是一种传统的航海指向仪器，目前仍是船舶必备的航海仪器之一。安装在钢铁船舶上的磁罗经除受地磁力作用外，还将受到船舶磁场的影响，致使罗经北偏离磁北方向一个夹角而产生自差。在钢铁船舶上，磁罗经自差一般可达到几十度之多，当自差较大时，在有些航向上由于磁北力被严重削弱，将影响罗经指向的稳定性；在船舶转向的过程中，由于罗经北相对地磁北极的夹角变化较大会出现转向时的迟钝现象；若磁罗经自差没有消除，将严重影响船舶的航行安全。鉴于船舶导航设备的日益完善以及磁罗经在船上所处的地位，能否在保证船舶航行安全的前提下，探讨简化校正磁罗经自差的方法，采用“人为航向法”消除磁罗经自差，对于中小型船舶来说是一种既简捷又实用的有效方法。这不仅可以提高船舶的经济效益，而且还可保证船舶航行安全。

关键词  船舶  磁罗经  自差 

The Artificial Direction Method of Eliminating The Magnetic Compass Deviation

[Abstract]  The magnetic compass is one traditional navigation direction instrument, at present was still one of ships necessary nautical instruments. Installs besides receives earth magnetism action of force on the steel and iron ships' magnetic compass, will also receive the ships magnetic field the influence, a cause compass north deviation magnetic north direction included angle produces the autodyne. On the steel and iron ships, the magnetic compass autodyne may achieve several dozens degree many generally, when the autodyne is big, in some directions, because the magnetic north strength is weakened seriously, will affect the compass direction the stability; Changes in the ships in process, when the compass north relative earth magnetism North Pole's included angle change compares the congress appears changes the slow phenomenon; If the magnetic compass autodyne has not eliminated, serious influence ships' navigation security. In view of the fact that the ship navigation equipment's day-by-day consummation as well as the magnetic compass the status which locates on the ship, whether under the guarantee ships navigation security's premise, the discussion simplification adjustment magnetic compass  method, the use “the artificial direction law” to eliminate the magnetic compass autodyne, regarding the middle and small scale ships is one kind both simple and direct and the practical efficacious device. Not only this may raise ships' economic efficiency, moreover may also assure the ships navigation security.

[Key words]  Vessel;   Magnetic  compass ;   deviation 

目  录

引 言 1
第1章 磁罗经自差及其校正 2
1.1 磁罗经自差的产生原因 2
1.1.1 磁罗经的指北原理 2
1.1.2 船体的磁性及其变化 2
1.1.3 船体磁性对磁罗经的影响 4
1.2　测校自差前的准备与检查 5
1.3 磁罗经自差的消除方法 6
1.3.1　船半圆自差硬铁力的准确消除 7
1.3.2 船软铁半圆自差力的准确消除 7
1.3.3　倾斜自差校正的不合理性 9
1.3.4　感应自差的变化 10
第2章 人为航向法 12
2.1 “人为航向法”的校正原理 12
2.2 “人为航向法”消除船用磁罗经自差的基本步骤 13
2.3 “人为航向法”消除船用磁罗经自差的几个具体问题 15
第3章 “人为航向法”实例分析及校差的探讨 18
3.1 实例分析 18
3.2 “人为航向法”校差的探讨 21
结束语 23
致谢语 24
参考文献 25