The present disclosure relates generally to the field of transportation and, in particular, toward vehicles used in transportation with reduced drag capabilities.
In fluid dynamics, drag is a force acting opposite to the relative motion of an object moving with respect to the surrounding fluid or gas. Drag can exist between two fluid layers (e.g., liquid or gas) or between a fluid and a solid surface of an object. To the extent that drag forces can be reduced for a vehicle moving through a fluid, the amount of force required to propel the vehicle through the fluid can be reduced. The reduction of drag forces almost always results in improved fuel efficiency or speed of travel for a vehicle.
The present disclosure is described in conjunction with the appended figures, which are not necessarily drawn to scale.
The ensuing description provides embodiments only, and is not intended to limit the scope, applicability, or configuration of the claims. Rather, the ensuing description will provide those skilled in the art with an enabling description for implementing the described embodiments. Various changes may be made in the function and arrangement of elements without departing from the spirit and scope of the appended claims.
Embodiments of the present disclosure will be described in connection with illustrative vehicles, which may or may not be configured to carry passengers as cargo. As used herein, the term “vehicle” may include any solid object that travels through a fluid (e.g., gas or liquid). A vehicle may or may not require some amount of propulsion to travel through the fluid. A vehicle travelling through the fluid may displace the fluid. It should be appreciated that by displacing fluid during travel, the vehicle may experience one or more drag forces at points where the fluid contact a solid surface of the vehicle (or at points where the solid surface of the vehicle contacts the fluid). Embodiments of the present disclosure propose mechanisms for reducing drag-induced forces that are presented to the vehicle by outputting one or more fluids in a way that effectively breaks the fluid through which the vehicle is traveling. Said another way, and in accordance with embodiments described herein, the vehicle may be equipped with one or more mechanisms that cause fluid to be expelled in front of or across a solid surface of the vehicle (e.g., outward from a forward-travelling surface), thereby creating a fluidic barrier between the primary fluid in which the vehicle is traveling (which may also be referred to as the traveling medium) and the solid surface(s) of the vehicle. While drag forces may still exist between the traveling medium and the expelled fluid and also between the expelled fluid and the solid surface(s) of the vehicle, it should be appreciated that such drag forces are reduced as compared to the drag forces that would be experienced by the vehicle in the absence of an expelled fluid being provided in front of or across the solid surface(s) of the vehicle.
As will be described in further detail herein, a vehicle may include one or more of an aircraft, watercraft, and/or land-traveling vehicle. Examples of a land-traveling vehicle include, without limitation, a truck, semi-truck, train, road train, tractor, motorcycle, passenger car, Sports Utility Vehicle (SUV), or the like. Examples of a water-traveling vehicle include a boat, a submarine, a freighter, a cruise ship, etc. Examples of an air-traveling vehicle include a plane, a rocket, a drone, etc.
Embodiments of the present disclosure contemplate the use of expelled fluid to not only reduce drag, but to also create an environment in front of a traveling vehicle where the traveling medium is disrupted prior to the solid surface of the vehicle impacting the traveling medium. This environment may further benefit travel of the vehicle because one or more vortices are moved away from the solid surface of the vehicle and could be considered to help propel the vehicle forward (in addition to other propulsion forces being applied to the vehicle). In other words, the utilization of an expelled fluid at the front of a vehicle may create an environment that is both propelling the vehicle and also exhibiting a reduced drag on the vehicle as compared to the vehicle impacting a still traveling medium.
With reference now to
As shown in
The output port(s) 204 may be configured as an opening, which may or may not have a controllable door provided at the entrance thereto, through which expelled fluid 208 can be provided. In some embodiments, the expelled fluid 208 is pushed out of the output port(s) 204 under a compression force, which may be provided by an air compressor that is housed internally within the body 104 of the vehicle 100. The expelled fluid 208 may correspond to the same fluid as the traveling medium (e.g., air) or the expelled fluid 208 may correspond to a different type of fluid than the traveling medium. As a non-limiting example, the expelled fluid 208 may correspond to pure oxygen or compressed oxygen whereas the traveling medium corresponds to air. In some embodiments, the compressed oxygen may be provided by a compression tank that is maintained for purposes of providing compressed oxygen to the cabin in the body 104 of the vehicle 100. Such compression tanks are already provided for purposes of allowing passengers of the vehicle 100 to breathe while the vehicle 100 is traveling at relatively high altitudes, which means that the already-existing compression tank can be dual-purposed to provide the expelled fluid 208 out of the one or more output ports 204. Alternatively or additionally, some of the expelled fluid 208 may correspond to fluid that is recaptured toward a back of the vehicle. For instance, exhaust of the propulsion unit 120 may be recaptured and converted into expelled fluid 208 without departing from the scope of the present disclosure. Other discarded fluids or contained fluids could also be recaptured and used for expelled fluid 208 alone or in combination with other fluids.
As shown in
Providing the expelled fluid 208 in the direction of travel may seem counterintuitive because the ejection of the expelled fluid 208 may be seen as counteracting the forces produced by the propulsion unit 120. However, the forces imparted by the expelled fluid 208 may be minimal as compared to the reduction in drag forces enabled by the expelled fluid 208 traveling the fluid path 304. In other words, the reduction in frictional forces traveling may be larger than the amount of backward forces imparted on the vehicle 100 by the expelled fluid 208.
In some embodiments, the expelled fluid 208 is output at a rate which is one or multiple orders of magnitude less than a mass flow rate produced by the propulsion units 120. In some embodiments, the propulsion units 120 may be configured to operate at a mass flow rate of at least 1,300 kg/s where the output ports 204 may output the expelled fluid 208 at a mass flow rate of less than 1 kg/s or 10 kg/s. Thus, the mass flow rate produced at the output ports 204 will not be enough to substantially counteract or provide a backwards propulsion force as compared to the propulsion units 120. However, the output ports 204 may still output enough expelled fluid 208 to effectively break or interrupt the traveling medium before the solid surface of the vehicle 100 impacts the traveling medium, which may be assumed to be substantially motionless with respect to the traveling vehicle 100.
In some embodiments, it may be possible to utilize one or more output ports 204 in connection with modifying or adjusting the lift applied to the vehicle 100 as the vehicle 100 travels through the air. As a non-limiting example, expelled fluid 208 may change the air speed traveling across the top and/or bottom of a wing, thereby changing the lift profile of the wing. It may be possible to precisely control the volume of expelled fluid 208 and the output ports 204 from which the expelled fluid 208 is dispensed in an effort to change the lift applied to the wings 116. It may also be possible to utilize the expelled fluid 208 to steer or change a direction of travel of the vehicle 100. For instance, providing expelled fluid 208 on a left side of the vehicle 100 and not providing as much (or no) expelled fluid 208 on the right side of the vehicle 100 may cause the vehicle 100 to turn left (e.g., toward the side where more expelled fluid 208 is being dispensed). This can be used in addition to traditional rudders and other direction-control devices of a vehicle 100.
With reference now to
The vehicle 400 is also shown to include one or more output ports 416 through which an expelled fluid 420 can be output. The expelled fluid 420 may be provided as a gas or liquid without departing from the scope of the present disclosure. Moreover, the number and placement of the various output ports 416 along the hull of the vehicle 400 may depend upon the hydrodynamic properties of the hull and which portions of the hull are considered to experience the most drag during operation. In some embodiments, as shown in
As can be seen in
In some embodiments, the fluidic cavity 436 may have the fluid therein compressed to a pressure that is greater than the pressure existing at the outside of the outer portion 424. The fluid within the fluidic cavity 436 may be compressed with a compressor 444 (or pump/hydraulic pump) under control of a fluid output controller 440. Thus, as the vehicle 400 is traveling and the hull is submerged in the traveling medium, at least some traveling medium may enter the fluidic cavity 436. The fluidic cavity 436 may be substantially sealed from the inside of the hull such that the compressor 444 is able to impart an increased pressure into the fluidic cavity 436. The amount of pressure provided by the compressor 444 may be controlled by the fluid output controller 440 and may be based upon a desired flow rate of expelled fluid 420. Alternatively or additionally, one or more output ports 416 may be provided with a movable port door 448 that is capable of being actuated or controlled by the fluid output controller 440 in such a way that certain of the output ports 416 are used to release expelled fluid 420 from the fluidic cavity 436 at a certain point in time whereas others of the output ports 416 have their corresponding movable port door 448 closed, thereby not allowing expelled fluid 420 to exit via that output port 416. Thus, the fluid output controller 440 may be provided with logic and communication capabilities to control the operation of the movable port door(s) 448 in addition to or in lieu of controlling operation of the compressor 444. Alternatively or additionally, the controller 440 could be configured to control operation of one or more flow valves that sit between a fluid container and the output ports 416. In this way, the fluid output controller 440 may adjust the behavior of the output ports 416 and/or the rate at which expelled fluid 420 is discharged from the output ports 416. This control may be achieved mechanically, via control of fluid control valves, and/or via pressurization of the fluidic cavity 436.
In other embodiments, rather than relying upon an improved hull design, the vehicle 400 may be provided with a simple compressed fluid tank and one or more hoses and fluid couplings may be connected between the compressed fluid tank and the output ports 416. In such a configuration, the fluid output controller 440 may control the amount of fluid provided to any one individual output port 416 from the compressed fluid tank, thereby controlling the flow rate of the expelled fluid 420.
It should be appreciated that the placement and/or design of the output ports 416 may vary depending upon the shape of the vehicle 400 and the desired dynamic properties of the output ports 416. In some embodiments, the shape/size of the output ports 416 may be relatively simple (e.g., circular shaped holes with or without one or more adjustable covers that slide directly over the hole, but are otherwise substantially flush with the outer portion 424 of the hull) or more complex (e.g., non-circular shaped openings with a movable port door 448 that moves along a hinge rather than sliding over the opening). Alternative configurations of output ports 416 and port doors 448 may also be used without departing from the scope of the present disclosure.
As can be seen in
As shown in
It should be appreciated that the vehicles 400, 500 (or any other vehicle depicted and described herein) may utilize expelled fluid as a propulsion mechanism in lieu of or in addition to utilize the expelled fluid to create a barrier between the solid surface(s) of the vehicle and the traveling medium. For instance, with respect to a ship's hull, the expelled fluid could be leveraged to reduce drag as described herein in addition to or in lieu of providing a separate propulsion system. The expelled fluid may also be used to control steering of the vehicle without departing from the scope of the present disclosure.
With reference now to
The rate at which expelled fluid 620 is dispensed may be controlled by a controller 644 that is integrated into the body 604 of the vehicle 600. The controller 644, as with other controllers depicted and described herein, may be configured to control an amount and/or rate with which fluid is dispensed from a fluid container 640 via a control line 648. In some embodiments, the fluid container 640 may be filled with a fluid prior to departure of the vehicle and once the entirety of the fluid is dispensed as expelled fluid 620, then no more fluid may be dispensed (e.g., because the fluid container 640 is empty). In other embodiments, motion of the vehicle 600 may cause the fluid container 640 to be refilled with surrounding fluid (e.g., fluid recaptured from motion of the vehicle 600 through the traveling medium). In such a situation, the controller 644 may also control a compressor or pump that causes a pressure within the fluid container 640 to be increased and enables the expelled fluid 620 to release from the output port 616 at a controlled rate.
In some embodiments, the controller 644 may be provided with logic that is capable of determining an altitude, speed, acceleration, or other ballistic property of the vehicle 600 and, in response thereto, may adjust the amount or rate with which the expelled fluid 620 is dispensed from the output port 616. The controller 644 may also be configured to discontinue dispensing fluid from the fluid container 640 under predetermined conditions (e.g., during initial takeoff or after the vehicle 600 has reached a predetermined altitude or is out of the atmosphere).
As can be seen in
In some embodiments, the front end 608 of the vehicle 600 may be provided with just two output ports 516 (e.g., one facing in one direction that is orthogonal to the direction of travel and another facing opposite to the first output port). Alternatively, the vehicle 600 may be provided with two, three, four, or more pairs of output ports 516 facing in many different directions, where each pair of output ports 516 are configured to output the expelled fluid 520, but in a way that no substantial steering forces are imparted on the vehicle 600 (unless the fluid 520 is desired to provide some steering forces). If steering is desired by using the expelled fluid 520, then it may be possible to, in a controlled manner, provide more expelled fluid 520 from one of the output ports 516 than the other of the output ports 516 that is facing in the opposite direction. This may result in a lateral force being exerted on the vehicle 600, but the amount of force exerted may depend upon the amount of expelled fluid 520, its flow rate, etc.
It should be appreciated that by using the output ports 516 as shown in
It should be appreciated that while pairs of output ports have been described herein, that similar functional goals can be achieved by an odd number of output ports that are symmetrically distributed around an object (e.g., wing 116, nozzle 804, etc.). The set of output ports (e.g., where the number of output ports is not necessarily even) may be configured to collectively cancel out each other's lateral forces, thereby providing a drag reducing function without necessarily impacting the direction of travel or lateral forces imparted on the vehicle. Of course, the expelled fluid 208 from the various output ports in the set of output ports could be controlled to not cancel out, but rather impart steering forces on the vehicle.
In some embodiments, the nozzle 804 may comprise a shared volume from which expelled fluid 208 is provided to both of the output ports 204. In other words, each output port 204 in the set of output ports on the nozzle 804 may receive their fluid from a common source, thereby helping to manage or control the amount/volume/rate with which the expelled fluid 208 is dispensed from each of the output ports 204.
Specific details were given in the description to provide a thorough understanding of the embodiments. However, it will be understood by one of ordinary skill in the art that the embodiments may be practiced without these specific details. Additionally, the Figures do not depict well-known features that may be needed to create a working vehicle so as not to obscure the embodiments in unnecessary detail.
The present application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Application Nos. 62/849,238, filed on May 17, 2019, and 62/843,208, filed on May 3, 2019, the entire disclosures of each of which are hereby incorporated herein by reference.
Filing Document | Filing Date | Country | Kind |
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PCT/US2020/030497 | 4/29/2020 | WO | 00 |
Number | Date | Country | |
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62849238 | May 2019 | US | |
62843208 | May 2019 | US |