Corkscrew Filter Extracts Liquid From Air Charge
Environment
Corkscrew Filter Extracts Liquid From Air Charge (MSC-TOPS-118)
Removes liquids and particulates from a saturated air charge without impinging upon flow
Overview
Innovators at NASA Johnson Space Center in collaboration with IRPI, LLC, have developed a compact inline filter that utilizes a unique multi-phase flow method to separate liquid from an incoming air charge. The filter also traps particulate matter and does so without significantly impinging upon flow velocity.
Unique to the filter is a multitude of helical (corkscrew-shaped) open flow channels that are impregnated into the filter element. Due to the constant curvature of the channels, the liquid and particulates from the incoming air charge are inertially dispersed onto the channel walls using centrifugal force. Wicking material holds the liquid in place, while stepped contours within the channels also help trap particulates.
Development of the filter was performed to provide the Orion Spacecraft with a method to absorb liquid water and particulates from the cabin atmosphere after a fire event and discharge of a water-based fire extinguisher. However, applications here on Earth have commercial viability for this high-flow phase separation technology. These applications may include vehicle or laboratory fire safety systems, petrochemical refining, water filtration, municipal solid waste derivatives, and wet/dry vacuum systems.
The Technology
In the event of a fire aboard the Orion Spacecraft, the Portable Fire Extinguisher (PFE) can introduce up to three pounds of water into the cabin to extinguish a fire. A filter was needed to work in conjunction with the Orion Fire Safety System (OFSS) to filter water out of the cabin atmosphere after dispersal from the PFE. Airflow introduced to the smoke filter of the OFSS must be dry and free of large particulates for the sorbent material to effectively extract smoke generated by a fire.
These moisture and particulate concerns prompted a re-design of the original filter, especially a filter that could be tested in Earth’s gravity and yielding results that would transfer to a microgravity environment. The newly designed filter uses a multi-phase flow separation method that allows the airflow to develop fully in a helical flow path. This flow path resides within a wicking material used to separate the liquid from the gas (air) while also trapping particulate matter.
Helical flow paths implemented in the filter impart a centrifugal force upon the incoming gas/liquid mixture that develops an asymmetric liquid film on the inner contour of the helix. Upon active airflow, the larger water droplets are inertially forced into the inner contour flow path wall. The flow path walls are made from a wicking material, and all liquid film and liquid droplets that are inertially deposited onto the walls are adsorbed into the filter material. The resulting output flow from the filter is 100% gas.
The Corkscrew Filter has a technology readiness level (TRL) of 5 (component and/or breadboard validation in relevant environment) and is now available for patent licensing. Please note that NASA does not manufacture products itself for commercial sale.
Benefits
- Compact size for a multi-phase filter
- Filters water and particulates from a gas charge
- Does not significantly impinge upon flow velocity
- Filtering element separates liquid
- Inexpensive to construct compared to other variants
- Can be constructed using commercial off-the-shelf materials
- Can function in gravity or microgravity environments
Applications
- Spaceflight systems
- Petrochemical refining
- Water filtration
- Solid waste processing
- Wet/dry vacuums
- Building and site construction
- Fire safety systems
- Clean rooms
|
Tags:
|
Similar Results
Multi-Stage Filtration System
While HEPA filter elements can last for years without intervention, pre-filtering systems that remove larger particles before they reach the HEPA filter need to be treated (most often by cleaning or replacement) as often as once a week. These treatments can be resource-intensive and expensive, especially in extreme environments. Glenn's innovative system combines a pre-filtration impactor and a scroll filter that reduces the need to replace the more sensitive or expensive filters, extending the system's working life. The system uses an endless belt system to provide the impaction surface. A thin layer of low-toxicity grease is applied to the impaction surface to increase particle adhesion. A high flow turning angle near the impaction surface causes relatively large particles to impact and stick to the surface while smaller particles stay within the air flow. When the surface is covered with particles - or if a layer of particles has grown to a thickness that impairs adhesion - the surface is regenerated. The band is rotated so that the loaded surface passes by a scrapper, removing the layer of particles and a clean segment of the band revolves to become the new impaction surface.
A further innovation is the scroll filter which allows the filtration media to be rotated out of the airflow when fully loaded, providing multiple changes of the filter through a motorized scrolling or indexing mechanism. When nearly fully loaded with dust particles, the exposed media is mechanically rolled up on one side of the filter to both contain and compactly store the dust. The spools that hold the clean and spent filter media are mounted on roller bearings to facilitate the scrolling operation and reduce motor power requirements. Nearly any grade of filter media can be used to meet the desired filtration specification. Additional media rolls can be added after the original roll is spent to further increase filter life.
Low Separation Force Quick Disconnect Device
The Low Separation Force Quick Disconnect device uses an innovative seal arrangement and flow path to eliminate separation force from line pressure. A radial design ensures a low separation force regardless of line pressure. Ten holes around the internal seal cancel loads due to balanced pressure; thus, the central force exerted on the device is due to the springs fixed internally. The device also provides for additional optional characteristics including a self-aligning feature from a compliant mount and a self-sealing mechanism that keeps dust out of the device.
The Low Separation Force Quick Disconnect device is designed to transport pneumatics and cryogenic fluid. Due to the low separation force and overall design, the system requires less heavy and high-strength support structures than conventional designs; the design permits lighter retention systems and reduces deflection variations.
Aerospace specific uses of the invention include flight-to-ground, flight-to-flight and surface-system applications. Other uses of the invention include any mechanism in which fluid is being transferred from ground to a vehicle or another system, especially where a high line pressure is used.
Filtering Molecules with Nanotube Technology
This water filtration innovation is an acoustically driven molecular sieve embedded with small-diameter carbon nanotubes. First, water enters the device and contacts the filter matrix, which can be made of polymer, ceramic, or metallic compounds. Carbon nanotubes within the matrix allow only water molecules to pass through, leaving behind any larger molecules and contaminants. The unique aspect of the technology is its use of acoustics to help drive water through the filter.
An oscillator circuit attached to the filter matrix propagates acoustic vibration, further causing water molecules to de-bond and move through the filter. This use of acoustics also eliminates dependence on gravity (and thus filter orientation) to move water through the device. When water exiting the system diminishes to a pre-determined set point, a cleaning cycle is triggered to clear the sediment from the inlet of the filter, reestablishing the standard system flow rate. Unlike other filtration systems, flushing of the filter system is not required. The combination of acoustics and small-diameter carbon nanotubes in this innovation make it an effective and efficient means of producing contaminant-free, clean water.
Liquid Sorbent Carbon Dioxide Removal System
NASA's Liquid Sorbent Carbon Dioxide Removal System was designed as an alternative to the current CO2 removal technology used on the International Space Station (ISS), which uses solid zeolite media that is prone to dusting, has a low absorption capacity, and requires high regeneration temperatures and frequent maintenance. Motivated by CO2 removal systems on submarines, NASA innovators began investigating the use of liquid sorbents. Liquid sorbents have a capacity four times greater than solid zeolites, require low regeneration temperature, and need fewer unreliable moving mechanical parts than solid based systems. While submarine CO2 scrubbers spray an adsorbing chemical directly into the air stream and allow the liquid to settle, NASA's new system uses a capillary driven 3D printed microchannel direct air/liquid contactor in a closed loop system. The Liquid Sorbent Carbon Dioxide Removal System is robust and reliable, while being low in weight, volume, and power requirements. The system is capable of reaching equilibrium when the liquid sorbent surface is being regenerated at a rate equal to the rate of absorption into the liquid.
Dust Tolerant Quick Disconnect With Self-Sealing Barrier
Dusty, dirty environments can be very tough on connectors. The abrasive nature of dust and dirt particles can rub and wear down connector surfaces through friction, and have a negative effect on coatings used on gaskets to seal equipment. Dust on umbilical connections can also make mating and de-mating electrical and fluid connections difficult, hazardous, and unreliable. NASA's Quick Disconnect (QD) design consists of columnar arrays of parallel filaments. All the pins of the electrical connector easily penetrate the barriers when the umbilicals are brought together. They are wiped clean of dust when they penetrate the barrier and mate cleanly and reliably. Likewise, the male end of a fluid connector penetrates the filament arrays of both connector ends. Since the filament arrays are oriented perpendicular to each other, the entire circumference of the connector is contacted by the filaments that stretch around, conform to, and sweep off dust from the mating surface ensuring a clean and secure connection.
