Helicopter Auxiliary System Using Pyro-Hydraulic Storage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing auxiliary systems for helicopter propulsion systems face challenges in terms of size, weight, and cost, particularly when providing mechanical power on an ad-hoc basis, and existing solutions either require large amounts of propellant or pose integration issues due to size and transport regulations.
Innovation Solution
A compact, lightweight auxiliary system utilizing a pyro-hydraulic storer that combines the energy density of pyrotechnic solutions with the power density of hydraulic systems, featuring a controlled hydraulic motor and a pyro-hydraulic storer with a solid propellant cartridge, which generates pressurized liquid to drive a relay shaft connected to the rotor, allowing for efficient mechanical power delivery without permanent pressure elements or electrical dependencies.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a solid propellant gas generator is used to provide mechanical power to the rotor during autorotation, then propulsive power is provided to ensure reliable autorotation, but a significant amount of propellant must be carried in the engine compartment, increasing weight and volume
Solution Approach 1:
The patent replaces the traditional solid propellant gas generator system with a hydraulic system that uses a hydraulic motor to drive the rotor. This substitution eliminates the need for carrying large amounts of propellant while maintaining the ability to provide mechanical power during autorotation, directly resolving the contradiction between reliability and weight
Solution Approach 2:
The invention introduces a hydraulic circuit with a hydraulic motor to replace the pneumatic/chemical propellant system. The hydraulic motor converts hydraulic energy into mechanical rotation to drive the rotor, providing the necessary propulsive power without the weight penalty of carrying substantial propellant reserves
2Reliability
If a pyrotechnic system is used to provide mechanical power, then emergency power is available, but the system is not sealed and contributes to gas emissions, creating transport regulation difficulties
Solution Approach 1:
The patent replaces the open pyrotechnic system with a closed hydraulic system. The hydraulic system is sealed, preventing gas emissions, while still providing the necessary emergency mechanical power through the hydraulic motor. This resolves the contradiction between emergency power availability and harmful emissions
3Reliability
If a hydraulic emergency starting device is used to provide mechanical starting power for a turboshaft engine, then engine restart capability is provided, but the system's bulk poses integration problems for certain helicopters
Solution Approach 1:
The patent designs a hydraulic system that serves multiple functions: it can drive the rotor during autorotation and also provide starting power for the turboshaft engine. This multi-functionality reduces the overall system volume compared to having separate systems for each function, resolving the contradiction between reliability and volume
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
The system provides reliable mechanical power assistance to helicopter propulsion systems, facilitating autorotation maneuvers and engine reactivation while meeting size, weight, and cost optimization criteria, with reduced logistical challenges and improved integration and certification.
Implementation Method 1
a main compartment comprising at least one solid propellant cartridge
Data Source
Figure 1~3
AI summary
The invention relates to an auxiliary system for mechanically driving a relay shaft (8) of a helicopter propulsion system, comprising: a hydraulic motor (7), mechanically connected to said relay shaft (8); a hydraulic circuit (10) for supplying a pressurised liquid to said hydraulic motor (7); a controlled, fast-opening hydraulic valve (11) arranged on the hydraulic circuit (10); a pyro-hydraulic storage unit (9) driven by a control unit (12) and connected to said hydraulic valve (11), said pyro-hydraulic storage unit (9) comprising: an enclosure (20) including a piston (16) that defines a main compartment (17) having at least one solid propellant cartridge (19) and a compartment (18) for a liquid supply; an ignition charge (25) connected to said main compartment (17) and suitable for initiating the combustion of at least one solid propellant cartridge (19) upon receiving a command from said control unit (12)