职业技能鉴定2022海船船员模拟考试练习题282

1. [单选题]在机舱航行值班时，如出现甲板火警警报，值班机工应()

A. 立即到甲板参加救火
B. 迅速做好弃船准备
C. 尽快协助值班轮机员向甲板提供消防水
D. 尽快撤离机舱

2. [单选题]If scavenge box should be hot, _______would occur.

A. seized piston
B. defective atomizer
C. scavenge fire
D. too much L.O

3. [单选题]SOLAS公约第Ⅱ章主要内容是关于______。

A. 无线电报^{(marconigram)}和无线电话
B. 救生设备和装置
C. 分舱和稳性
D. 航行安全

4. [单选题]If you install a new hydraulic hose in a hydraulic system, the hose must be long enough to allow for contraction to prevent

A. failure of the hydraulic hose
B. excessive flow through the line
C. friction in other areas of the hydraulic system
D. overheating of the hydraulic fluid

5. [单选题]An alternator is being paralleled with one on the line At the instant the circuit breaker is close, the frequency of the incoming alternator will normally

A. increase
B. not change
C. decrease
D. be exactly 60 hertz

6. [单选题]第一组： The Wartsila 50DF operates on the lean-bum principle: the mixture of air and gas in the cylinder has more air than is needed for complete combustion. Lean combustion reduces peak temperatures and therefore NOx emissions. Efficiency is increased and higher output is reached while avoiding knocking. Combustion of the lean air-fuel mixture is initiated by injecting a small amount of LFO (pilot fuel) into the cylinder. The pilot fuel is ignited in a conventional diesel process, providing a high-energy ignition source for the main engine. To obtain the best efficiency and lowest emissions, every cylinder is individually controlled to ensure operation at the correct air-fuel ratio and with the correct amount and timing of pilot fuel rejection. Wartsila has developed a special electronic control system to cope with the demanding task of controlling the combustion in each cylinder, and to ensure optimal performance in terms of efficiency and emissions under all conditions by keeping each cylinder within the operating window. Stable and well-controlled combustion also contributes to less mechanical and thermal load on the engine components. Current stringent emission regulations demand the reduction of NOx emissions. In an internal combustion engine this means controlling peak temperature and residence time, which are the main parameters governing NOx formations. In the Wartsila 50DF engine, the air-fuel ratio is very high (typically 2.2). Since the same specific heat quantity released by combustion is used to heat up a larger mass of air, the maximum temperature and consequently NOx formation are lower. The mixture is uniform. throughout the cylinder since the fuel and air are premixed before introduction into the cylinders, which helps to avoid local NOx formation points within the cylinder. Benefiting from this unique feature, NOx emissions from the Wartsila 50DF are extremely and comply with the most stringent existing legislation.What is the combustion feature of the Wartsila 50DF?

A. Lean air in the cylinder
B. Excessive fuel in the cylinder
C. Excessive air in the cylinder
D. Spark ignition

7. [单选题]在用水灭火时，应在消防栓的阀门怎样时，把水带、水枪铺设好？

A. 打开之前
B. 打开之后
C. B均可
D. 在打开过程中

8. [单选题]贴近水面飞行的地效船和非排水状态的气垫船^(hovercraft)在互见中相遇（不在狭水道或IMO采纳的分道通航制水域），则下列说法不正确的是：I、地效船不应妨碍气垫船^(hovercraft)；II、地效船应给气垫船^(hovercraft)让路；III、气垫船^(hovercraft)应给地效船让路

A. III
B. II、III
C. I、II、III
D. I、II

9. [单选题]某轮由已知到达点纬度为26°24＇.6N，两地间纬差为08°06＇.2N，则起航点纬度为：()

A. 18°18＇.4N
B. 15°47＇.8N
C. 34°30＇.8N
D. 15°12＇.2N

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