悉尼大学(The University of Sydney):燃气轮机和燃

发布时间:2019-10-19 18:18

Even the diesel engine is now under development for running combined-cycle where the exhaust heat produces steam for a turbine (HOT Combustion). Plant efficiency between 55 and 60% is expected.
即使是柴油发动机,是目前正在开发运行联合循环排热产生用于涡轮机的蒸汽(HOT的燃烧)。预期工厂的效率在55%和60%之间。


These combined plants will be more attractive the bigger they are. It is difficult to set an exact
MW limit, but looking at the new COGES cruise vessels, the plant is typically above 50MW.
Thermal efficiency is here expected to be close to 45% [Diesel&Gas Tubine, 1999].
这些组合的工厂将更具吸引力更大。这是很难设定一个确切兆瓦的限制,但在新COGES邮轮,厂房通常是50MW以上。这里预期的热效率接近45%


The progress made on generators, motors and power converters also urges for more extensive use of electrical power trains in ships. It also opens for combination of prime movers (diesels and turbines) and optimising of operation adapted the different operational modes.
所取得的进展发电机,电动机和电源转换器还敦促更广泛地使用在船舶电力列车。它也开辟组合(柴油发动机和涡轮机)的主要推动者和优化的操作适应不同的操作模式。


For the case ship categories herein the diesel engine as prime mover will be dominating also the next twenty years. The fixed propeller drive will probably see more competition from the alternatives (SSP, Azipod, Compass etc).
此处的情况下船舶类别的柴油发动机为原动机将主导未来二十年。固定螺旋桨驱动器可能会看到更多的替代品的竞争。


Gas turbines:
燃气轮机


An increased focus from the gas turbine manufacturer on the merchant marine marked is expected in the time to come. The “fight” between diesel and turbine suppliers will probably intensify and urge development for better energy efficiency.
增加了重点标记的商船从燃气轮机制造商,有望在今后的时间。柴油和涡轮机供应商之间的“打架”,可能会加剧,并敦促开发更好的能源效率。


Where power density (kW pr. ton or m3 installation) is important, the gas turbine is favourable compared to the diesel engine. NOx emissions can be as low as 0.5-1.0 g/kWh using the latest low NOx techniques. These techniques are also foreseen developed and implemented for transient operated marine turbines. However, shaft efficiency is still not competing with the diesels. But development is going on for making more efficient marine turbines. Shaft efficiency in the range of 40-42 % is reported (Rolls-Royce WR21 propulsion module, turbine with recuperation).
功率密度(千瓦公关吨或立方米安装)重要的是,燃气涡轮机是有利的相比,柴油发动机。氮氧化物排放量可以低至0.5-1.0克/千瓦时,采用了最新的低NOx技术。制定并实施瞬态供电海洋涡轮机,这些技术也预见。


A major drawback for the gas turbine is the requirement to fuel quality. In contrary to a diesel engine, the gas turbine cannot be run on HFO. But a future market switch from HFO to MDO driven by mechanism released by SOx emission limitations can contribute to outweigh some of the fuel quality drawback of the gas turbine.
功率密度(千瓦公关吨或立方米安装)重要的是,燃气涡轮机是有利的相比,柴油发动机。氮氧化物排放量可以低至0.5-1.0克/千瓦时,采用了最新的低NOx技术。制定并实施瞬态供电海洋涡轮机,这些技术也预见。


Fuel cells (EEC 1994, CARB 1998):
燃料电池


Fuel cells are here discussed under ”alternative prime movers”, although it is just as much “alternative fuelling” as hydrogen is the fuel. The fuel cells in question all utilise hydrogen as working media in the cell itself. However, different fuels can be used/stored onboard (i.e. methanol, nat. gas etc.), but then a reformer is needed to separate and supply pure hydrogen to the cell.
燃料电池是在这里所讨论的“另类原动力”,虽然它是一样多的“另类加油”氢是燃料。所有的燃料电池利用氢气作为工作介质中的细胞本身。


Fuel cell drive concepts with highly efficient electric drive systems can provide a fuel-efficient, zero emission propulsion concept for the future. Fuel cells are up to three times as efficient as the internal combustion engine with mechanical transmission systems and therefore seem to be one of the most promising option for clean and low-noise propulsion of the future. Achievable fuel efficiencies range in the order of 40 % - 50 % for internal combustion engines and of 45 %- 75 % for methanol or hydrogen fuel cell powered electric drives.
达到的燃料效率的范围在40%的顺序用于内燃机和45% - 50% - 75%的甲醇或氢燃料电池供电的电动驱动器。


Weight and volume are two significant limitations for the fuel cell technology, partly because of the low volume/energy ratio of hydrogen even in liquid phase. The limitation for applicability in larger scale is connected to more or less the same problems as for direct hydrogen use (storage, production and refuelling). In literature the fuel cell efficiency is normally reported as very high. These figures do not take into account the great energy losses (in the range of 40%) by making the hydrogen fuel. It is also so that fuel cells have their best efficiency in the load range around 30-50%, not as ideal for ship propulsion as for powering cars. Current fuel cells PEMFC for the transportation have a power density of 1200 W/m3 and 700 W/ton and a lifetime of 4-5 years.
The actual types of cells for use in ships are the PAFC (Phosphoric Acid fuel cell   http://www.ukassignment.org/azdxassignment/  ) and the PEMFC (Proton Exchange Membrane fuel cell) cell, both utilising hydrogen as fuel.
一般使用的细胞的实际类型的磷酸燃料电池(PAFC),质子交换膜燃料电池质子交换膜燃料电池细胞,无论是利用氢作为燃料。


The main challenges from now on for these alternatives are increase of power density (space and weight), fuel storage, complexity, investment cost, full load efficiency and lifetime. In parallel with fuel cell development and increased applicability, it is assumed that technology and availability for refuelling also will follow to meet market needs. A major question will also
be how to make the hydrogen fuel in the future in the most efficient way.
从现在开始,使用这些替代品的主要挑战是增加功率密度(空间和重量),燃料储存,复杂性,投资成本,满负荷效率和寿命。与燃料电池的开发和增加适用性的同时,它假定技术和可用性也会跟着加油,以满足市场的需求。


When discussing fuel cells and emissions it is important not to forget the overall CO2 account, included also from hydrogen production. If methanol is used as basis for hydrogen conversion, the fuel cell CO2 benefit is significantly reduced. Technology on fuel cells using hydrogen as fuel has moved forward. There is still put great resources in the fuel cell development programs, and it is expected great improvements in unit/system capacity and costs. The driving force is the automotive industry.
在燃料电池发展计划,仍投入了很大的资源,并预计很大的改进单元/系统容量和成本的驱动力是汽车行业。


In the near future it is foreseen pilot projects with fuel cells also in the marine sector, then probably in the auxiliary power systems. A prediction for the next two decades do not expect the fuel cell to play any major role as main power for ships.
在不久的将来,预计试点项目,还与燃料电池在海洋领域,那么很可能在辅助动力系统。未来二十年的预测并不指望发挥燃料电池为主要动力的船舶任何重大的作用。

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