MDE Unit 4 Q1

A main engine turbocharger is a device used to increase the power output of a marine diesel engine. It does this by utilizing the energy from the engine’s exhaust gases to compress and force more air into the engine’s combustion chambers.  

1. Marine Turbocharger

2. Turbocharger – Wikipedia

How it works:

• Exhaust gases: The engine’s exhaust gases are channeled through a turbine, causing it to spin.   1. How a Turbocharger Works | Cummins www.cummins.com
• Turbine shaft: The turbine is connected to a compressor via a shaft.   1. How a Turbocharger Works | Cummins www.cummins.com
• Compressor: As the turbine spins, it drives the compressor, which forces more air into the engine’s intake manifold.
• Increased power: The additional air in the combustion chamber allows for more fuel to be burned, resulting in increased power and torque.

Benefits of a turbocharger:

Reduced emissions   1. How turbochargers can support the decarbonization journey – Accelleron accelleron-industries.com

Increased engine power and torque   1. The fundamentals of turbocharging – Accelleron accelleron-industries.com

Improved fuel efficiency   1. Turbocharger Fuel Efficiency: Driving Smart – Goldfarb & Associates Inc goldfarbinc.com

Faster engine response

Turbochargers generate a significant amount of heat due to the high-speed rotation of the turbine and compressor wheels. To prevent damage and ensure optimal performance, they require effective cooling. This is achieved through a combination of methods:  

1. The importance of cooling in turbochargers: avoids overheating – Turbo3

2. Boost Your Knowledge: The Ultimate Guide to Turbochargers – Turbosmart

1. Oil Cooling:

• Lubrication: The engine oil circulates through the turbocharger, providing lubrication for the moving parts.   1. How Are Most Turbochargers Lubricated? | [2023] – Goldfarb & Associates Inc goldfarbinc.com
• Heat dissipation: The oil also absorbs heat from the turbocharger components, helping to maintain operating temperatures.   1. Turbocharger Cooling System – Goldfarb & Associates Inc goldfarbinc.com

2. Water Cooling:

• Some turbochargers: Larger or higher-performance turbochargers may incorporate water cooling.   1. Water Cooling For Your Turbo – Main Benefits – Garrett Motion www.garrettmotion.com
• Heat reduction: Water is circulated through specific passages in the turbocharger to further reduce temperatures.
• Improved durability: Water cooling helps to extend the life of the turbocharger by preventing overheating.   1. Water Cooling For Your Turbo – Main Benefits – Garrett Motion www.garrettmotion.com

3. Intercooler:

• Air cooling: While not directly cooling the turbocharger itself, the intercooler cools the compressed air coming from the turbocharger.   1. Intercoolers: How do they work? – Garrett Motion www.garrettmotion.com
• Improved engine efficiency: Cooler air is denser, resulting in better combustion and increased power.   1. How Air Temperature Affects Your Air Intake System’s Performance – Gexhaust gexhaust.com

It’s important to note that the specific cooling methods used will vary depending on the turbocharger’s design and the engine application.

A turbocharger is lubricated by the engine’s oil supply. The same oil that lubricates the engine’s internal components also flows through the turbocharger to keep it running smoothly.  

1. Turbocharger lubrication – Ajusa Gaskets

2. How Are Most Turbochargers Lubricated? | [2023] – Goldfarb & Associates Inc

Lubrication process:

1. Oil supply: Engine oil is pumped through oil galleries to the turbocharger.   1. How Are Most Turbochargers Lubricated? | [2023] – Goldfarb & Associates Inc goldfarbinc.com
2. Bearing lubrication: The oil lubricates the bearings supporting the turbocharger’s shaft, reducing friction and wear.   1. How Are Most Turbochargers Lubricated? | [2023] – Goldfarb & Associates Inc goldfarbinc.com
3. Cooling: The oil also helps to cool the turbocharger’s components, preventing overheating.   1. The importance of cooling in turbochargers: avoids overheating – Turbo3 turbo3.com
4. Oil return: The used oil is returned to the engine’s oil sump for recirculation.   1. How Are Most Turbochargers Lubricated? | [2023] – Goldfarb & Associates Inc goldfarbinc.com

It’s crucial to use the correct type and viscosity of oil for the turbocharger. The oil needs to withstand the high temperatures and pressures generated within the turbocharger.  

1. Turbocharger maintenance: why do they need the correct type of oil?

2. Boost Your Knowledge: The Ultimate Guide to Turbochargers – Turbosmart