User:TannerJamesHill/Open microfluidics

Zero Gravity (Microgravity) Fluidics
In extraterrestrial conditions, such as zero gravity (also called microgravity), fluid dynamics are controlled via the geometry and wetting properties within the system. In microgravity, surface tension is the dominant force because buoyancy effects become negligible. In microfluidic conditions surface tension forces are also dominating. Both microgravity and microfluidics are also controlled through adhesion between the liquid and the cavity wall. Therefore, microfluidics are highly applicable for fluidic transport, handling, or other processes in microgravity. Beverage cups, carbon dioxide removal, life support systems, water recycling, and more can utilize capillary flow for operation in space. Capillary forces also allow for effortless and complete drainage of storage tanks and fuel tanks. This is more efficient in both weight reduction and complete usage of resources. Astronauts are exposed to several conditions that inevitably make them more likely to become sick. Research is being done on performing molecular diagnostic tests in space.

Fuel cells
"Further information: Electroosmotic pump"Microfluidic fuel cells (MFCs) use laminar flow to separate the fuel and its oxidant to control the interactions without the physical barrier that conventional fuel cells require. Using a liquid membrane can lead to clogging of the device. With laminar flow, build up is washed away. NASA has used alkaline fuel cells since the mid-1960s. These rely on a porous matrix saturated with an aqueous alkaline solution which benefits from having a laminar flow. The ability to closely tailor the flow of two or more liquids and the diffusion limited reaction rate of laminar flow allow microfluidic biofuel cells, which use enzymes or microorganisms to convert chemical to electrical energy, to operate more efficiently as well. Tailoring the anolyte and catholyte compositions also enables the optimization of enzymatic activity and stability.

Other fuels used in microfluidic fuel cells include vanadium species, hydrogen, hydrocarbons, hydrogen peroxide, borohydride, glucose, methanol, formic acid, and nitrogenous materials. In some devices, a single pass, 100% of these fuels can be utilized. Vanadium MFCs can be fabricated by rapid prototyping costing only $2 each. The major downside is their toxicity making them dangerous in commercial and portable electronics. Stacking the cells can increase the working voltage. Each one provides ~1.2 V. Borohydride and hydrazine MFCs however provide ~1.6 V. There is still considerable research to be done towards optimization, miniaturization, cost efficiency and determining the conditions in which the cells can operate and in which they operate most effectively.