Limitations of air-cooled diesel engine

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Working Of Air-Cooled Diesel Engine
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• The air-cooled cooling system uses air as the
  cooling medium. The high-speed moving air
  generated by the fan removes the heat of the
  high-temperature parts, permitting the air cooled
  diesel engines to operate at the optimum
  temperature.
• Makers arrange heat sinks on the outer wall of
  the cylinder and the cylinder head to increase
  the heat dissipation area. We also arrange an air
  hood and a baffle to properly distribute the
  cooling air and improve the air utilization rate.
  The cooling effect is more effective and uniform.

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Air-Cooled Diesel Engine

• The air-cooling system comprises a heat sink, a
  fan, an air hood, and a deflector. Compared with
  the water-cooling system, the air-cooling system
  has the advantages of few parts, simple
  structure, the lightweight of the whole machine,
  convenient use and maintenance, and good
  adaptability to regional environmental changes.
• However, the air cooled diesel engines also has
  large noise and a high heat load. The fan
  consumes a large amount of power and has a low
  aeration coefficient.

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Parts Of Cooled Diesel Engine

• The diesel engine cooling system works using a
  centrifugal fan. The centrifugal fan of a cooled
  air diesel engine is often cast together with a
  flywheel, placed at the rear end of the diesel
  engine, and drives through the crankshaft.
• Air is drawn axially from the air inlet and the
  airflow from the fan volute directly by the air
  hood to the cylinder and cylinder head for
  cooling. The arrangement is simple and compact,
  and there is no special fan driving mechanism
  the cooling airflow has less turning, and the
  flow resistance is small.
• The axial fan drives through the crankshaft
  through the V-belt at the front end of the diesel
  engine. The air flows axially, sucked by the fan,
  and pressed into the air chamber composed of the
  air hood, and each cylinder cools, and then the
  air flows out through the splitter plate.
• The difference between air-cooled generator set
  and water-cooled generator set Diesel generator
  sets generate a lot of heat during normal
  operation. Excessive heat will cause the unit
  temperature to rise, which will affect the
  working efficiency. Therefore, the cooling system
  needs equipping to reduce the temperature. Common
  cooling systems are water-cooled and air-cooled.

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• An air-cooled diesel engines uses large fans to
  force the exhaust air to dissipate heat from the
  generator body. Its advantages are simple
  structure, good maintenance, no freezing cracks
  or hot boiling danger.
• The generator set limit by thermal and mechanical
  load, the power is generally small, and the power
  conversion rate of the generator set is
  relatively low, which is not energy-saving. The
  air-cooled machine needs installation in an open
  cabin, which requires high environmental
  requirements and high noise. It needs treatment
  in the room for noise reduction. The air-cooling
  method is more applicable to small gasoline
  generators and low-power diesel generator sets.
• In a water-cooled generator set, the water
  circulates inside and outside the body, taking
  away the heat generated inside the body through
  the heat-dissipating water tank and the fan. Both
  functions dissipate heat in the air, and there is
  not much difference in the use.
• The advantage of the water-cooled is that the
  cooling effect is ideal, the cooling is rapid and
  stable, and the power conversion rate is high.

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• The installation site of the water-cooled system
  has small limitations, low environmental
  requirements, low noise, and a remote cooling
  system. Water cooling methods apply to small
  diesel generators and high-power diesel generator
  sets. The common diesel generator brands on the
  market are Cummins, Perkins, MTU (Mercedes-Benz),
  Volvo Shangchai, and Weichai.
• Air-cooled systems make use of air circulation to
  cool the system. Withair-cooled systems, the
  engine takes in cooler air from the atmosphere,
  blowing it internally across the generator set,
  keeping the generator from overheating.
• Typically, air-cooled engines are for portable
  generators and standby generators with a capacity
  of up to 22 kilowatts.

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With Air-Cooled Systems, You Have Two Options

• ? Open ventilated systems
• ? Completely enclosed
• Open ventilation systems use atmospheric air and
  release the exhaust is into the atmosphere. On
  the other hand, enclosed ventilation systems keep
  re-circulating the air to cool the internal
  generator parts.
• Limitations of air-cooled diesel engine
• Air-cooled engines have some limitations
• ?They can overheat if used for a long duration in
  excessive heat, so we recommend being aware of
  the ambient temperature and duration of use.
• ?When air-cooled engines fail, there is the
  potential for needing significant repairs. The
  preventative maintenance and repair tasks require
  a more attentive approach compared with
  liquid-cooled systems.
• Air-cooled engines are slightly less robust as
  oil breaks down quickly in hotter conditions,
  leading to damage occurring without any warning.

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Liquid Cooled Generator Systems

• Liquid-cooled systems use several types of
  oil/coolant to cool the internal generator parts.
  Liquid-cooled systems offer much better cooling
  thanair-cooling systems, which is why
  liquid-cooled KOHLER generators price higher
  than air-cooled units. Essentially, liquid-cooled
  engines are comparable to small car engines.
• Liquid-cooling systems include a radiator and
  water pump. The pump distributes the liquid
  coolant to the engine block through hosesthe
  heat transfers to the coolant, which directs
  through the radiator where the air cools.
• Generally, modern generators above 22 kW utilize
  liquid-cooling, with air-cooled engines
  dominating portable generators.
• Liquid-cooling systems are more expensive to
  produce than air-cooled diesel engines they
  require additional design consideration and
  parts, including a radiator.
• They are more durable and powerful than
  air-cooled diesel engine counterparts. Since
  these generator sets are more expensive, in use
  for commercial and industrial purposes where the
  cooling demand is larger than small residential
  and portable units.

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Which System Do You Need?

• Every system comes with pros and cons. Air-cooled
  systems are simpler and less expensive than
  liquid-cooled systems. Liquid-cooled systems are
  more robust and effective. The cooling system you
  choose should be sufficient for your needs.
  Air-cooled systems are capable of the range of
  their utilization. Unless the ambient temperature
  is exceedingly hot, most residential generators
  will have no problem cooling via air.

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Conclusion

• The article is all about the mechanism of an
  air-cooled diesel engines. We have established a
  comparison between liquid-cooled diesel and
  air-cooled diesel engines to understand better
  the context, which will help you make the best
  choice.

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