Dual Mode Propulsion System for Amphibious Aircraft
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current air vehicles with seafaring capabilities are limited in their utility on water, as their propulsion systems are optimized for flight and provide only limited functionality on the water's surface, restricting their ability to perform duties like search and rescue, surveillance, and law enforcement.
Innovation Solution
A dual mode propulsion system combining a high pressure gas generator and a hydrojet engine, allowing efficient operation both in flight and on water, with a single propulsion system that includes a high pressure gas generator and a dual mode ejector nozzle for both high speed atmospheric and waterborne operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a single propulsion system optimized for flight is used in amphibious vehicles, then the vehicle can take off and land on water, but the propulsion system provides only limited functionality on the water's surface
Solution Approach 1:
The propulsion system is designed to perform multiple functions by operating in two distinct modes: as a conventional jet engine during flight and as a hydrojet pump when in contact with water. The same exhaust nozzle serves dual purposes - ejecting hot gases during flight and pumping water during water operations, eliminating the need for separate propulsion systems for air and water environments
Solution Approach 2:
The system dynamically adapts its operation based on environmental conditions. During flight, the exhaust nozzle ejects hot gases for propulsion. When the vehicle contacts water, the same nozzle transitions to pumping water, with the water itself serving as the propellant. This dynamic switching enables the system to optimize performance for each environment without requiring separate propulsion systems
2Speed
If amphibious aircraft rely on propulsion systems best suited to flight, then the vehicle can operate as an aircraft, but the vehicle is limited to merely taxiing on the water's surface
Solution Approach 1:
The single propulsion system provides universal functionality across both air and water environments. During flight, it operates as a high-speed jet engine. During water operations, it transforms into a hydrojet pump capable of propelling the vehicle at significant speeds across the water surface, enabling activities beyond mere taxiing such as search and rescue, surveillance, and law enforcement operations
Solution Approach 2:
The system uses the water environment itself as the propellant source during water operations. By positioning the exhaust nozzle to contact the water surface, the vehicle pumps and ejects water for propulsion, eliminating the need for separate fuel systems or propellants for waterborne operations
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables vehicles to perform a range of tactical duties such as search and rescue, surveillance, and law enforcement by maintaining long loiter capabilities on the water and quick return to base, with efficient propulsion in both environments.
Implementation Method 1
a high pressure gas generator (such as but not limited to a gas turbine, pulsejet or pulse detonation engine (PDE)) enables high speed operation in both the air
Implementation Method 2
This inlet is in operation whenever the vehicle is operating under its own power in the air or at sea. A second inlet is used for water intake during waterborne operations or air intake during airborne operations of the vehicle.
Implementation Method 3
The high pressure gas generator exhaust/secondary fluid (e.g. water) mixture moves through a mixing region which may be convergent, divergent or substantially straight, is ejected out the back of the vehicle through the common nozzle, thus creating propulsive force.
Data Source
AI summary
A system or method of propelling a vehicle with a multimodal propulsion system is provided. This multimodal propulsion system includes a primary inlet, a high-pressure gas generator, a gas generator exhaust system, a secondary fluid inlet, and a propulsion exhaust system. The primary inlet receives an incoming fluid flow that is provided to the high-pressure gas generator. The high-pressure gas generator coupled to the primary inlet produces a high-pressure exhaust from the incoming fluid flow. The high-pressure gas generator exhaust and secondary inlet couple to the propulsive exhaust system which mixes the two flow streams. The secondary flow may be gaseous or liquid fluid flow such as air flow for airborne flight and water for waterborne operation. The mixed fluid flow is expelled by the propulsive exhaust system that can propel the vehicle.