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32-503: Designed by Léon Levavasseur and Jules Gastambide, and baptized with the name "Monobloc", the aircraft featured a number of innovative aerodynamic refinements for its time. The design was characterized by an enclosed and streamlined body and wings. The design reduced air resistance by the absence of any external bracing wires, and by having its control cables totally enclosed within its quadrangular-section fuselage and large wooden cantilever wings. The wooden wings were 70 cm thick at

64-401: A commitment by the military to purchase 10 aircraft. The competition attracted the major French aircraft manufacturers of the time, including Blériot , Farman , Deperdussin and Nieuport . Despite the fitting of a more powerful V12 engine of 100 hp and a smaller 16 litre fuel tank, Antoinette's Monobloc entry was under-powered and, though it may have managed a short hop of several metres, it

96-404: A single image or with a video stream—may be used to provide insight in the flow and its history. If a line, curve or closed curve is used as start point for a continuous set of streamlines, the result is a stream surface . In the case of a closed curve in a steady flow, fluid that is inside a stream surface must remain forever within that same stream surface, because the streamlines are tangent to

128-466: Is a time of interest. In steady flow (when the velocity vector-field does not change with time), the streamlines, pathlines, and streaklines coincide. This is because when a particle on a streamline reaches a point, a 0 {\displaystyle a_{0}} , further on that streamline the equations governing the flow will send it in a certain direction x → {\displaystyle {\vec {x}}} . As

160-450: Is steady, so that they can use experimental methods of creating streaklines to identify the streamlines. Knowledge of the streamlines can be useful in fluid dynamics. The curvature of a streamline is related to the pressure gradient acting perpendicular to the streamline. The center of curvature of the streamline lies in the direction of decreasing radial pressure. The magnitude of the radial pressure gradient can be calculated directly from

192-451: Is the pressure gradient and ∂ c ∂ s {\displaystyle {\frac {\partial c}{\partial s}}} the velocity gradient along the streamline. For a steady flow, the time derivative of the velocity is zero: ∂ c ∂ t = 0 {\displaystyle {\frac {\partial c}{\partial t}}=0} . g {\displaystyle g} denotes

224-699: Is the velocity of a particle P {\displaystyle P} at location x → {\displaystyle {\vec {x}}} and time t {\displaystyle t} . The parameter τ P {\displaystyle \tau _{P}} , parametrizes the streakline x → s t r ( t , τ P ) {\displaystyle {\vec {x}}_{str}(t,\tau _{P})} and t 0 ≤ τ P ≤ t {\displaystyle t_{0}\leq \tau _{P}\leq t} , where t {\displaystyle t}

256-425: The vector cross product and x → S ( s ) {\displaystyle {\vec {x}}_{S}(s)} is the parametric representation of just one streamline at one moment in time. If the components of the velocity are written u → = ( u , v , w ) , {\displaystyle {\vec {u}}=(u,v,w),} and those of

288-488: The 1911 military contest at Reims in September-October 1911 a larger V12 engine of 100 hp was fitted. This was cooled by steam — heated water evaporated in the cylinder jackets and then condensed in copper tubing attached to the outside of the aircraft. The engine had two valves per cylinder, a mechanically operated exhaust valve and an automatic inlet valve. Instead of a carburetor, two fuel pumps delivered fuel to

320-565: The French Army, this competition required that the aircraft and engines be fully built in France, and be able to fly without stop on a closed circuit of 300 km with a 300 kg load (not including oil, water and fuel) at a speed of more than 60 km/h. Additionally, they were to be 3-seaters, and be able to take-off and land from unprepared surfaces. The first prize was 700,000 francs plus additional sums for increases in speed over 60 km/h, as well as

352-429: The base and 25 cm at the ends, with internal bracing and built around four square steel spars . The main spar was 70 cm high and fixed at the front third of the wing; the others (i fore, 2 aft) hinged in the middle of their axes, allowing the wings to ' warp ' to provide lateral control of the machine. These were controlled by the pilot by a distortable frame which could be pushed for-and-aft or side-to-side for controlling

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384-411: The curvature of the front surface can be much steeper than the back of the object. Most drag is caused by eddies in the fluid behind the moving object, and the objective should be to allow the fluid to slow down after passing around the object, and regain pressure, without forming eddies. The same terms have since become common vernacular to describe any process that smooths an operation. For instance, it

416-406: The curves are parallel to the velocity vector. Here s {\displaystyle s} is a variable which parametrizes the curve s ↦ x → S ( s ) . {\displaystyle s\mapsto {\vec {x}}_{S}(s).} Streamlines are calculated instantaneously, meaning that at one instance of time they are calculated throughout

448-414: The density of the fluid, the curvature of the streamline and the local velocity. Dye can be used in water, or smoke in air, in order to see streaklines, from which pathlines can be calculated. Streaklines are identical to streamlines for steady flow. Further, dye can be used to create timelines. The patterns guide design modifications, aiming to reduce the drag. This task is known as streamlining , and

480-532: The direction s {\displaystyle s} of the streamline is denoted by c {\displaystyle c} . r {\displaystyle r} is the radius of curvature of the streamline. The density of the fluid is denoted by ρ {\displaystyle \rho } and the kinematic viscosity by ν {\displaystyle \nu } . ∂ p ∂ s {\displaystyle {\frac {\partial p}{\partial s}}}

512-425: The equations that govern the flow remain the same when another particle reaches a 0 {\displaystyle a_{0}} it will also go in the direction x → {\displaystyle {\vec {x}}} . If the flow is not steady then when the next particle reaches position a 0 {\displaystyle a_{0}} the flow would have changed and

544-446: The flow changes with time, that is, when the flow is not steady . Considering a velocity vector field in three-dimensional space in the framework of continuum mechanics , we have that: By definition, different streamlines at the same instant in a flow do not intersect, because a fluid particle cannot have two different velocities at the same point. However, pathlines are allowed to intersect themselves or other pathlines (except

576-780: The flow velocity. A scalar function whose contour lines define the streamlines is known as the stream function . Dye line may refer either to a streakline: dye released gradually from a fixed location during time; or it may refer to a timeline: a line of dye applied instantaneously at a certain moment in time, and observed at a later instant. Streamlines are defined by d x → S d s × u → ( x → S ) = 0 → , {\displaystyle {d{\vec {x}}_{S} \over ds}\times {\vec {u}}({\vec {x}}_{S})={\vec {0}},} where " × {\displaystyle \times } " denotes

608-862: The fluid from the instantaneous flow velocity field . A streamtube consists of a bundle of streamlines, much like communication cable. The equation of motion of a fluid on a streamline for a flow in a vertical plane is: ∂ c ∂ t + c ∂ c ∂ s = ν ∂ 2 c ∂ r 2 − 1 ρ ∂ p ∂ s − g ∂ z ∂ s {\displaystyle {\frac {\partial c}{\partial t}}+c{\frac {\partial c}{\partial s}}=\nu {\frac {\partial ^{2}c}{\partial r^{2}}}-{\frac {1}{\rho }}{\frac {\partial p}{\partial s}}-g{\frac {\partial z}{\partial s}}} The flow velocity in

640-712: The gravitational acceleration. Pathlines are defined by { d x → P d t ( t ) = u → P ( x → P ( t ) , t ) x → P ( t 0 ) = x → P 0 {\displaystyle {\begin{cases}{\dfrac {d{\vec {x}}_{P}}{dt}}(t)={\vec {u}}_{P}({\vec {x}}_{P}(t),t)\\[1.2ex]{\vec {x}}_{P}(t_{0})={\vec {x}}_{P0}\end{cases}}} The subscript P {\displaystyle P} indicates that we are following

672-510: The inlet valve chambers. A larger engine of V16 configuration and 120 hp was planned, but this may not have been possible due to limited space between the engine and the crew's entry hatch located underneath the fuselage. The aircraft was exhibited at Le Grand Concours d'Aviation Militaire at Reims in September 1911 in the hope of attracting orders from the French military. Organized by

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704-1299: The motion of a fluid particle. Note that at point x → P {\displaystyle {\vec {x}}_{P}} the curve is parallel to the flow velocity vector u → {\displaystyle {\vec {u}}} , where the velocity vector is evaluated at the position of the particle x → P {\displaystyle {\vec {x}}_{P}} at that time t {\displaystyle t} . Streaklines can be expressed as, { d x → s t r d t = u → P ( x → s t r , t ) x → s t r ( t = τ P ) = x → P 0 {\displaystyle {\begin{cases}\displaystyle {\frac {d{\vec {x}}_{str}}{dt}}={\vec {u}}_{P}({\vec {x}}_{str},t)\\[1.2ex]{\vec {x}}_{str}(t=\tau _{P})={\vec {x}}_{P0}\end{cases}}} where, u → P ( x → , t ) {\displaystyle {\vec {u}}_{P}({\vec {x}},t)}

736-423: The particle will go in a different direction. This is useful, because it is usually very difficult to look at streamlines in an experiment. However, if the flow is steady, one can use streaklines to describe the streamline pattern. Streamlines are frame-dependent. That is, the streamlines observed in one inertial reference frame are different from those observed in another inertial reference frame. For instance,

768-453: The resulting design is referred to as being streamlined . Streamlined objects and organisms, like airfoils , streamliners , cars and dolphins are often aesthetically pleasing to the eye. The Streamline Moderne style, a 1930s and 1940s offshoot of Art Deco , brought flowing lines to architecture and design of the era. The canonical example of a streamlined shape is a chicken egg with the blunt end facing forwards. This shows clearly that

800-413: The starting and end points of the different pathlines, which need to be distinct). Streaklines can also intersect themselves and other streaklines. Streamlines and timelines provide a snapshot of some flowfield characteristics, whereas streaklines and pathlines depend on the full time-history of the flow. However, often sequences of timelines (and streaklines) at different instants—being presented either in

832-472: The streamline as x → S = ( x S , y S , z S ) , {\displaystyle {\vec {x}}_{S}=(x_{S},y_{S},z_{S}),} we deduce d x S u = d y S v = d z S w , {\displaystyle {dx_{S} \over u}={dy_{S} \over v}={dz_{S} \over w},} which shows that

864-401: The streamlines in the air around an aircraft wing are defined differently for the passengers in the aircraft than for an observer on the ground. In the aircraft example, the observer on the ground will observe unsteady flow, and the observers in the aircraft will observe steady flow, with constant streamlines. When possible, fluid dynamicists try to find a reference frame in which the flow

896-403: The wing warping. The spars were supported by ribs spaced 40 cm apart; the wings, fully loaded, were designed to bear about 25 kg per m — when the current aircraft of the time only were designed to bear 15 kg/m. The chord of each wing was 4 metres at the junction with the fuselage, and decreased to 3 metres at the wing tip. The upper side of the wing's airfoil was cambered, while the under side

928-400: Was closed, so access was through a door under the fuselage. Seated at the front was the mechanic, who had easy direct access to the engine at the front. Behind him, the pilot had a good range of vision, with windows in the floor enabling him to see beneath him. An observer sat behind the pilot in the rear. The enclosure of the aircraft's fixed landing gear by streamlined fairings or "spats"

960-466: Was unable to successfully fly. It failed to attract any orders, and following this setback, the Antoinette company soon went into bankruptcy. Data from collated from various sources listed below General characteristics Related lists List of aircraft (pre-1914) streamlined Streamlines , streaklines and pathlines are field lines in a fluid flow . They differ only when

992-438: Was very flat, with the leading and trailing edges being quite sharp. The tailplane included a long, low fin and a large rectangular rudder that could be enlarged by an extension. The streamlined fuselage was decked over with wood frames and tight canvas, with only the cylinder-head of the engine exposed. The fuselage terminated at the front by a bow shaped like that of a boat. The crew compartment had three seats lined up and

Antoinette military monoplane - Misplaced Pages Continue

1024-583: Was viewed as a remarkable innovation in 1911. Each fairing consisted of a canvas-covered structure containing a large double main wheel on a flexibly sprung axle, and a smaller wheel placed forward to avoid nose-overs on landing. A similar arrangement was used by the Coandă 1911 twin-Gnôme engine monoplane. Acting as a radiator, a network of copper tubes running along the fuselage cooled the Antoinette 8V engine of 50 to 60 hp (according to different sources). For

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