In an embodiment, an article comprises a plurality of structural units, wherein each structural unit comprises a first portion; a second portion; wherein the second portion contacts the first portion; and a third portion; wherein the third portion is in communication with the first portion and the second portion and is more compressible than the first portion and the second portion; where the first portion has a first value of a property and where the second portion has a second value of the same property, such that the first value acts as a restraining or enhancing force on the second value; wherein the first portion comprises a first metal and wherein the second portion comprises a second metal that is different from the first metal.

The invention provides a method for computational fluid dynamics and apparatuses making enable an efficient implementation and use of an enhanced jet-effect, either the Coanda-jet-effect, the hydrophobic jet-effect, or the waving-jet-effect, triggered by specifically shaped corpuses and tunnels. The method is based on the approaches of the kinetic theory of matter providing generalized equations of fluid motion and is generalized and translated into terms of electromagnetism. The method is applicable for slow-flowing as well as fast-flowing real compressible-extendable generalized fluids and enables optimal design of convergent-divergent nozzles, providing for the most efficient jet-thrust. The method can be applied to airfoil shape optimization for bodies flying separately and in a multi-stage cascaded sequence. The method enables apparatuses for electricity harvesting from the fluid heat-energy, providing a positive net-efficiency. The method enables generators for practical-expedient power harvesting using constructive interference of waves due to the waving jet-effect.

The invention provides a method for computational fluid dynamics and apparatuses making enable an efficient implementation and use of an enhanced jet-effect, either the Coanda-jet-effect, the hydrophobic jet-effect, or the waving-jet-effect, triggered by specifically shaped corpuses and tunnels. The method is based on the approaches of the kinetic theory of matter providing generalized equations of fluid motion and is generalized and translated into terms of electromagnetism. The method is applicable for slow-flowing as well as fast-flowing real compressible-extendable generalized fluids and enables optimal design of convergent-divergent nozzles, providing for the most efficient jet-thrust. The method can be applied to airfoil shape optimization for bodies flying separately and in a multi-stage cascaded sequence. The method enables apparatuses for electricity harvesting from the fluid heat-energy, providing a positive net-efficiency. The method enables generators for practical-expedient power harvesting using constructive interference of waves due to the waving jet-effect.

A system includes a surface, an actuator, and processing circuitry. The surface includes one or more non-actuating zones and one or more actuatable zones. The actuator is configured to a flow property of a fluid that flows over the one or more actuatable zones of the surface. The processing circuitry is configured to obtain a value of a parameter of the fluid that flows over the surface, and operate the actuator to adjust the flow property of the fluid that flows over the one or more actuatable zones based on the value of the parameter of the fluid.

Systems and methods are described herein to implement transverse momentum injection at low frequencies to directly modify large-scale eddies in a turbulent boundary layer on a surface of an object. A set of transverse momentum injection actuators may be positioned on the surface of the object to affect large-scale eddies in the turbulent boundary layer. The system may include a controller to selectively actuate the transverse momentum injection actuators with an actuation pattern to affect the large-scale eddies to modify the drag of the fluid flow on the surface. In various embodiments, the transverse momentum injection actuators may be operated at frequencies less than 10,000 Hertz.

Systems and methods are described herein to implement transverse momentum injection at low frequencies to directly modify large-scale eddies in a turbulent boundary layer on a surface of an object. A set of transverse momentum injection actuators may be positioned on the surface of the object to affect large-scale eddies in the turbulent boundary layer. The system may include a controller to selectively actuate the transverse momentum injection actuators with an actuation pattern to affect the large-scale eddies to modify the drag of the fluid flow on the surface. In various embodiments, the transverse momentum injection actuators may be operated at frequencies less than 10,000 Hertz.

Fluid systems and methods for addressing fluid separation are described. An example fluid system includes a main body and a fluid pressurizer. The main body has a first portion, a second portion, an injection opening, a suction opening, a channel that extends from the suction opening to the injection opening, and a side wall. The first portion has a first axis that extends along the side wall. The second portion has a second axis that extends along the side wall at an angle relative to the first axis such that when fluid flows over the main body flow separation is defined adjacent to the second portion. The injection opening is disposed at a first location relative to said flow separation. The suction opening is disposed at a second location relative to said flow separation. The channel extends from the suction opening to the injection opening.

Fluid systems and methods for addressing fluid separation are described. An example fluid system includes a main body and a fluid pressurizer. The main body has a first portion, a second portion, an injection opening, a suction opening, a channel that extends from the suction opening to the injection opening, and a side wall. The first portion has a first axis that extends along the side wall. The second portion has a second axis that extends along the side wall at an angle relative to the first axis such that when fluid flows over the main body flow separation is defined adjacent to the second portion. The injection opening is disposed at a first location relative to said flow separation. The suction opening is disposed at a second location relative to said flow separation. The channel extends from the suction opening to the injection opening.

The invention pertains to the use of an easy-to-clean soft fiber-coated material on the underwater surface of structures to mimic mammal pelage and as such reducing residual drag, wherein said material comprises or consists of fibers having an average fiber length between 0.3 and 4 mm, and an average fiber thickness between 5 and 80 μm. The underwater surface of structure is preferably the hull of a movable or moving vessel, or the underwater part of a static structure such as offshore wind monopiles and off-shore rigs. In some embodiments, the invention pertains to the reduction of fuel consumption of a nautical vessel passing through water.

The invention pertains to the use of an easy-to-clean soft fiber-coated material on the underwater surface of structures to mimic mammal pelage and as such reducing residual drag, wherein said material comprises or consists of fibers having an average fiber length between 0.3 and 4 mm, and an average fiber thickness between 5 and 80 μm. The underwater surface of structure is preferably the hull of a movable or moving vessel, or the underwater part of a static structure such as offshore wind monopiles and off-shore rigs. In some embodiments, the invention pertains to the reduction of fuel consumption of a nautical vessel passing through water.