- The shape and geometry of the combustion chamber is very important from the point of view of creating turbulence in the combustion space. As the air enters through the air inlet valve, exhaust gas is blown out through the opened exhaust valve. During this time, the incoming air will always follow the geometry of the combustion space.
- The geometry of the combustion space governs the movement of the incoming air and exhaust gas. This creates a large amount of turbulence, which will be useful in the proper combustion of the fuel, and thus increase the thermal efficiency of the engine.
- Also, turbulence is created because of the shape of the crown of the piston which is part of combustion chamber geometry.
- As the air enters the chamber, it will hit against the crown of the piston and create turbulence due to change in direction, leading to greater combustion of the fuel.
1. High cost: Manganese bronze is a costly alloy, making it less economical for large propellers. 2. Low strength-to-weight ratio: Compared to other propeller materials like nickel-aluminum bronze or stainless steel, manganese bronze has a lower strength-to-weight ratio. 3. Susceptible to corrosion: Manganese bronze can corrode in seawater, especially when exposed to high velocities and turbulence. 4. Poor cavitation resistance: Manganese bronze is more prone to cavitation damage than other materials. 5. Difficult to cast and machine: Manganese bronze is challenging to cast and machine, making it less desirable for complex propeller geometries. 6. Limited weldability: Manganese bronze has poor weldability, making repairs and modifications difficult. Nickel-aluminum bronze or stainless steel are commonly used for propellers due to their: - High strength and durability - Excellent corrosion resistance - Good cavitation resistance - Ease of casting and machining - Weldability
Comments
Post a Comment
If you have any doubts.Please let me know