MDE Unit 4 Q5

Labyrinth glands are a type of seal used in turbochargers to prevent leakage between different sections of the turbocharger. They are particularly important in preventing the mixing of hot exhaust gases with lubricating oil.  

1. Turbocharger Sealing Rings: Critical for reducing carbon emissions – Cross Manufacturing

2. LABYRINTH SEAL|TURBOCHARGER| WHERE AND WHY FITTED|HOW IT WORK

Purpose of Labyrinth Glands:

• Prevent oil leakage: They help to contain the lubricating oil within the turbocharger, preventing it from entering the exhaust system or the intake air.
• Prevent gas leakage: Labyrinth glands also prevent exhaust gases or compressed air from entering the lubrication system, which could contaminate the oil and cause engine damage.   1. LABYRINTH SEAL|TURBOCHARGER| WHERE AND WHY FITTED|HOW IT WORK m.youtube.com

How they work:

• Multiple grooves: Labyrinth glands consist of a series of grooves or chambers that create a tortuous path for any fluid trying to leak.   1. Labyrinth seal – Wikipedia en.wikipedia.org
• Friction reduction: The complex path increases the fluid’s resistance, making it difficult to pass through the seal.

By creating a maze-like structure, labyrinth glands effectively prevent leakage while minimizing friction compared to other sealing methods.

Opens in a new windowwww.youtube.com

labyrinth gland

A diffuser is a critical component in the compressor section of a turbocharger. Its primary function is to convert the high-velocity air leaving the impeller into static pressure.  

1. Turbocharger Fundamentals – DieselNet

2. Air is sucked into the impeller eye and whirled outwards at high speed by the impeller disk. – Nptel

How it works:

• The impeller imparts high kinetic energy to the air.   1. Turbocharger Fundamentals – DieselNet dieselnet.com
• The diffuser, with its gradually increasing cross-sectional area, slows down the high-velocity air.   1. Diffuser: Meaning, Applications & Thermodynamics Equations – StudySmarter www.studysmarter.co.uk
• As the air slows down, its kinetic energy is converted into static pressure, increasing the air density.

Importance of the Diffuser:

• Improved compressor efficiency: By efficiently converting kinetic energy into static pressure, the diffuser enhances the compressor’s overall efficiency.   1. Turbocharger Fundamentals – DieselNet dieselnet.com
• Reduced turbulence: The diffuser helps to reduce turbulence in the airflow, which can improve compressor performance and reduce energy losses.
• Increased air density: The higher static pressure achieved by the diffuser results in denser air entering the combustion chamber, leading to improved engine power and efficiency.

Essentially, the diffuser plays a crucial role in optimizing the turbocharger’s performance by maximizing the pressure rise while minimizing energy losses.

The inducer is the first stage of the compressor in a turbocharger. It’s designed to efficiently increase the pressure of the incoming air as it enters the compressor section.

Purpose of the Inducer:

• Initial compression: The inducer is responsible for the initial compression of the intake air, which helps to reduce the load on the subsequent compressor stages.
• Improved efficiency: By efficiently compressing the air at the inlet, the inducer contributes to the overall efficiency of the turbocharger.
• Reduced shock losses: The inducer helps to reduce shock losses that can occur at the inlet of the compressor, improving airflow and performance.

By effectively compressing the air at the initial stage, the inducer plays a crucial role in optimizing the performance of the turbocharger.

A thrust bearing in a diesel engine turbocharger is essential for counteracting axial forces.

These forces arise due to:

• Pressure differentials: The pressure difference between the inlet and outlet sides of the compressor and turbine creates axial forces pushing the rotor in one direction.
• Rotor imbalance: Even slight imbalances in the rotor can result in axial forces during rotation.

The thrust bearing is designed to withstand and distribute these forces, preventing damage to the turbocharger shaft and ensuring its proper operation. By doing so, it maintains the alignment of the compressor and turbine wheels, optimizing their efficiency.

Essentially, the thrust bearing is crucial for the turbocharger’s longevity and performance.