screw propeller
Học thuậtThân thiện
Definition
Noun: A type of propulsion device consisting of a central hub with several angled blades (typically three or more) radiating from it. The entire assembly rotates on a shaft, and its helical (screw-like) motion pushes against a fluid—most commonly water or air—to generate thrust and propel a vehicle forward.
Usage
The term "screw propeller" specifically describes the mechanical device itself. It is a technical term commonly used in marine and aeronautical engineering contexts. - It is used to describe the primary propulsion system for most ships and boats. - It can also refer to similar devices used in aircraft (propellers) or certain types of fans.
Examples
- The ship's screw propeller was damaged after hitting a submerged log.
- Early aviation pioneers experimented with different designs for the screw propeller to achieve greater efficiency.
- The efficiency of a screw propeller depends on the pitch and shape of its blades.
Advanced Usage
- "Twin-screw propeller": A propulsion setup for a vessel using two independent propellers on separate shafts, typically for improved maneuverability.
- The large ferry was equipped with a twin-screw propeller system.
- The concept is fundamental to propeller theory, which analyzes the fluid dynamics of how a rotating screw generates thrust.
Variants and Related Words
- Propeller (n): A more common and general term for a device with rotating blades that creates thrust. "Screw propeller" is a specific type of propeller.
- Prop (n): An informal shortening of "propeller."
- Screw (n): In nautical contexts, "screw" is often used alone as a synonym for a ship's propeller (e.g., "the ship's screw").
- Rotor (n): While a rotor also has rotating blades, it typically refers to the lifting device of a helicopter or the rotating part of a turbine, not usually a direct synonym for propulsion.
Synonyms
- Propeller
- Marine propeller (when specifying use in water)
- Aircrew (archaic or very specific term for an aircraft propeller)
Related Phrases
- Feathering the propeller: An action on some aircraft to rotate the propeller blades to a minimal drag position, often when an engine fails.
- Variable-pitch propeller: A propeller where the angle (pitch) of the blades can be adjusted during operation for optimal performance at different speeds.
Noun
- a propeller with several angled blades that rotates to push against water or air