Rotatable Turret Window Air Foil for Low-Torque Flow Control

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Electro-optical and infrared turrets experience electro-optical resolution losses due to airflow turbulence, and existing air foils generate excessive aerodynamic torque, limiting operational airspeed when looking aft.

Innovation Solution

A movable air foil with a truncated reduced width portion that can rotate around the turret window to minimize aerodynamic torque and maintain optical performance across various viewing angles, reducing peak aerodynamic torque by nearly 87% while maintaining approximately 75% of the optical improvement of a full-sized foil.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a complete air foil is used to control fluid flow over the window, then optical performance is improved, but aerodynamic torque increases excessively

Engineering Contradiction:

Improveoptical performanceVSAvoidaerodynamic torque

Core Design Contradiction:

ReliabilityVSForce

Solution Approach 1:

The air foil is divided into a fixed portion and a movable portion that can rotate independently. The movable portion includes a truncated reduced width portion that segments the aerodynamic surface, allowing the turret to reduce aerodynamic torque by rotating the movable portion away from the airflow when looking aft, while maintaining optical performance when needed.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The air foil transitions from a static complete structure to a dynamic system where the movable portion can rotate relative to the fixed portion. This dynamic adjustment allows the turret to optimize between two conflicting requirements: maintaining full aerodynamic protection for optical performance versus reducing aerodynamic torque for high-speed operation when looking aft.

Inventive Principle:

Principle #15Dynamics

2Measurement precision

If a complete air foil is used to maintain optical performance, then electro-optical resolution is improved, but operational airspeed is limited

Engineering Contradiction:

Improveelectro-optical resolutionVSAvoidoperational airspeed

Core Design Contradiction:

Measurement precisionVSSpeed

Solution Approach 1:

The rotatable movable portion enables dynamic configuration adjustment based on operational requirements. When high electro-optical resolution is needed, the movable portion is positioned to maintain complete flow control. When operational airspeed is prioritized during aft-looking operations, the movable portion rotates to reduce aerodynamic torque, enabling higher speeds without sacrificing the ability to restore optical performance when needed.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The system changes the aerodynamic parameter configuration by rotating the movable portion. This parameter change allows transition between two operational states: one optimized for electro-optical resolution with complete air foil coverage, and another optimized for operational airspeed with reduced aerodynamic torque through the truncated configuration.

Inventive Principle:

Principle #35Parameter changes

3Force

If the air foil width is reduced to minimize aerodynamic torque, then aerodynamic torque is reduced, but optical improvement is compromised

Engineering Contradiction:

Improveaerodynamic torqueVSAvoidoptical improvement

Core Design Contradiction:

ForceVSReliability

Solution Approach 1:

The air foil is segmented into fixed and movable portions, with the movable portion containing the truncated reduced width section. This segmentation allows the system to present a reduced width profile to minimize aerodynamic torque when needed, while the fixed portion maintains sufficient width to preserve optical improvement capabilities when the movable portion is rotated into position.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The truncated reduced width portion applies partial aerodynamic action rather than complete coverage. This partial action is sufficient to significantly reduce aerodynamic torque (by nearly 87% according to the patent) while maintaining approximately 75% of the optical improvement of a full-sized foil, representing an optimized balance between the two competing requirements.

Inventive Principle:

Principle #16Partial or excessive action

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 greater operational airspeeds by minimizing aerodynamic torque and maintaining optical performance, allowing for improved imaging capabilities across a wider field of regard.

Implementation Method 1

an air foil that is attached to a window of a turret housing to minimize undesirable density gradients and effectively reduces optical wave front error

Methodology Applied

Scientific EffectFluid flow control:

Implementation Method 2

these air foils generate excessive aerodynamic torque when the turret is looking aft

Methodology Applied

Scientific EffectAerodynamic torque:

Data Source

PatentEP3554942B1Device and method for controlling fluid flow over an optical instrument

Publication Date: 2022.02.16 RAYTHEON CO

Figure 1~2
Figure 3~4
Figure 5~6

AI summary

A device is provided for controlling fluid flow over a window of a movable optical instrument housing. The device includes a generally annular body having an inner peripheral edge configured to correspond to a peripheral edge of the window of the housing and an outer peripheral edge, an arcuate outer surface disposed between the inner peripheral edge and the outer peripheral edge, and a reduced width portion between the inner peripheral edge and the outer peripheral edge. The reduced width portion is configured to lower elevation torque. Other embodiments of the device and methods for controlling fluid flow are further disclosed.