Wind Tunnel Seeder Hood with Collision Surface for Particle Separation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional seeding devices for wind tunnel tests produce tracer particles with varying diameters, leading to increased cleaning time and cost due to adherence of particles with diameters 4 μm or larger to the tunnel surfaces, and oil droplets from adhering particles can scatter into the wind tunnel, causing stains.
Innovation Solution
A seeding device with a hood that deflects airflow and tracer particles, featuring a collision surface inclined at 45° to trap larger particles and a flange at the opening to prevent oil droplet scattering, ensuring only smaller particles enter the wind tunnel, while a drain hole collects and recycles oil droplets.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If tracer particles with diameter of 4 μm or larger are used, then the tracer particles are likely to adhere to wall surface and floor surface of wind tunnel, but this increases cleaning time and cost
Solution Approach 1:
The patent extracts and removes large-diameter tracer particles (4 μm or larger) from the particle stream before they enter the wind tunnel. This is achieved by positioning a collision surface in the particle flow path, where larger particles collide and adhere to the surface, while smaller particles continue through to the tunnel. This extraction mechanism directly addresses the contradiction by preventing problematic particles from entering the system, thereby reducing cleaning time while maintaining reliable particle tracking with the remaining smaller particles.
2Manufacturing precision
If a hood is provided to guide air and tracer particles, then large-diameter particles are trapped on inner surface, but oil droplets from adhering particles are pushed by air flow and scatter into wind tunnel causing stain
Solution Approach 1:
The patent extracts and removes the harmful oil droplets generated from adhering particles by providing a dedicated collection mechanism. The hood structure includes features that capture and collect these oil droplets before they can scatter into the wind tunnel, thereby eliminating the staining problem while maintaining the particle separation function.
Solution Approach 2:
The patent introduces an intermediary collection mechanism within the hood that acts as a barrier between the adhering particles and the wind tunnel. This intermediary structure captures oil droplets and prevents their scattering, thereby mediating between the particle separation function and the prevention of staining.
3Device complexity
If tracer particles with various diameters are produced by conventional seeding devices, then the seeding device is simple, but it is difficult to prevent generation of particles with diameter of 4 μm or larger
Solution Approach 1:
The patent segments the particle flow path into distinct zones: a first region where particles are generated, a second region containing the collision surface for particle separation, and a third region leading to the wind tunnel. This segmentation allows the simple seeding device to work in conjunction with the collision surface to achieve particle diameter control, separating the generation function from the selection function while maintaining overall system simplicity.
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
Significantly reduces the supply of large-diameter particles into the wind tunnel, minimizing adherence and staining, and efficiently collects and recycles oil droplets, simplifying cleaning and reducing operational costs.
Implementation Method 1
tracer particles having a large diameter fly straightly without being drifted by the deflected air and collide with the collision surface and are trapped thereon. Thus, the tracer particles having a large diameter are prevented from being supplied into the wind tunnel.
Implementation Method 2
a hood which covers the nozzle and the collision surface on an upstream side in an airflow direction in the wind tunnel, and which has an opening formed therein on a downstream side in the airflow direction
Data Source
AI summary
Tracer particles together with air are jetted from a nozzle of a seeder into a hood, the air is guided by a collision surface of the hood, deflected to a downstream side in an airflow direction in a wind tunnel, and flows out into the wind tunnel through an opening of the hood. Tracer particles having a large diameter fly straightly without being drifted by the deflected air and collide with the collision surface and are trapped thereon and are prevented from being supplied into the wind tunnel. Tracer particles having a small diameter are drifted by the deflected air, thereby deflected, and supplied into the wind tunnel without collision with and adhesion to the collision surface.