INSTEAD OF SAIL — ROTOR

Apparently, in the technical work appeared in the phenomenon that can be called bottle-modeling. The fact that modelers in different fields are increasingly used… plastic bottles. From these light and sturdy vessels, they made a great hull models of yachts and catamarans, compressed-air cylinders to drive the action of the compressed air motors air and car. Thin clear plastic was the ideal material for the manufacture of lamps for aircraft models.

And here is another model design that uses plastic vessels. It is a catamaran with an original rotary wind propulsion.

First a few words about how the rotor appears driving aerodynamic force. It has been noticed that if you put a rotating cylinder into the air flow, the cylinder will apply a force perpendicular to the direction of flow. The fact that the rotation of the cylinder the direction of movement of one part of its surface coincides with the direction of air flow, and rotation to the opposite end — towards him.

In accordance with the Bernoulli law, establishing the conformity of the air flow speed and pressure with increasing flow rate the pressure in it decreases. When blowing the rotating cylinder in the zone with oncoming traffic the cylindrical surface and the flow pressure is less than in the area with associated movement of the cylindrical surface and air. The appearance of a pressure difference causes a force directed perpendicular to the motion of vozduho-d flow from areas of greater pressure to a zone of lower pressure.

From time to time attempts were made to use rotors to drive ships. One of the most successful should be called the propeller, mounted on the research vessel of Jacques-Yves Cousteau, the Calypso. The rotating cylinders are mounted in a diametrical plane of the vessel, allow for ocean passages to save a lot of fuel.

Model of a catamaran with rotary wind mover:

1 — cross the bridge (plywood s15. 2); 2— platform bridge (pine, rail 60×15); 3 — the rotor housing; 4—anterior part of body of model of catamaran; 5 — keel; 6 — posterior part of the body of the catamaran; 7 — steering gear; 8— washer; 9 — a bolt M5; 10 — distance washer (rubber); 11 —nut M5; 12,17,21,22 — wide washers (steel); 13 — nut valve (2 PCs.); 14 — valve with a valve (Bicycle inner tube); 15—screw-threaded tube; 16—sealing washer (rubber); 18 — spacer (aluminum); 19 — bearing (2 PCs); 20 — rotor shaft (steel); 23 — nut M6; 24 — bearing housing (aluminum)

It should be noted that the rotors on “Calypso” to spin a small auxiliary motor. However, the results show good device and driven in rotation by the air stream.

In the proposed model catamaran rotors also spin up the air flow. Each of the rotors is a plastic bottle, the surface of which there are many blades when blowing a bottle mounted vertically on the bearing receives axial rotation.

However, the manufacturer of catamaran makes sense to start with the buildings — for every need two and a half – or two-liter bottles. Plastic receptacles in a single enclosure bottoms are joined and are connected with a M5 bolt, nut and washers— two steel and one rubber. This docking result is very rigid and provides absolutely accurate alignment. The fact that the bottom protrusions of one container fall into the depression of another.

For such connections require special tools — a screwdriver with an elongated tip and a long Allen key. To introduce the hardware inside the bottles, bolt, nut and washer can stick to the tools of conventional clay.

Scheme of formation of the aerodynamic forces when rotating blower rotor

The rudder of a catamaran:

1 — pad (birch, rack 12×10, 2); 2 — plate (plywood s5)

The body of the rotor (base of the rotor— a plastic bottle 1.5 or 2 l)

In tubes of all four bottles are inserted valves from Cycling cameras — with their help the body are attached by nuts to the cross bridges. In addition, through the valves can be conventional velencoso to create inside the housing air pressure, which greatly increases their rigidity.

The thus prepared housings are mounted in a single catamaran with bridge, consisting of a platform (the pine plank section 60×15 mm) and two crossbars (plywood, 15 mm thick). The details of the bridge are connected to long screws, diameter 4 mm. In cross drilled holes under the valves. Ready the bridge barked, painted and covered with two or three coats of varnish parquet.

The keel of the catamaran cut from plywood 5 mm thick, in the upper part of the epoxy stick two birch block. The front part of the keel has the round rear soshlifovat on the wedge. The finished keel barked and covered with two layers of varnish parquet. Optionally, if the stability of the catamaran is insufficient, at the end of the keel to hang the bulb lead. The attachment of the keel to the platform of the bridge with the four screws with a diameter of 4 mm.

The steering device consists of a plywood catamaran steering pen and axis-tiller. Latest curved 4-mm steel wire and one end tapped M4. Steering the pen has a symmetric profile with rounded front and pointed rear edges. Decorating pen standard: grinding, painting and coating, parquet varnish.

Connecting the pen with the axis of the tiller, all-in-one — on epoxy glue. However, if it is necessary to periodically disassemble the catamaran, when gluing in the pen axis thread it should be coated with a thin layer of grease. After curing of the resin, the axis will easily come unscrewed from the pen. Mount the steering gear on the platform of the bridge — a couple of nuts and washers.

And now the main manufacturer of the rotary engine. As already mentioned, each of the rotors is a hinged platform and a half – or two-liter plastic bottle with a lot of bent blades on the surface. When blowing an air stream so the rotor starts to rotate. The blades came out of the same and as neat as a working tool for cutting the wall of the bottle, a rotor, it is desirable to use elektrovyzhigatel or homemade electrotermic.

Homemade electrochromatic:

1 — cutting part (nichrome, wire d0,5); 2 — porcelain pad (on lamp cartridge); 3 — knob (from a file); 4 — connecting a two-wire cord

Steering gear:

1 —axis-tiller (steel, wire, d4); 2— platform bridge; 3 — M4 nuts; 4 — steering pen (plywood s6); 5 — washer

The latter is easily gathered from the wooden handle of the file, the porcelain pad from the cartridge filament and nichrome wire with a diameter of 0.5 mm. is Fed to the tool from Later. The voltage must provide a heating nichrome wire to plastic only melted, but in no case did not burn.

Mark the outline of the blade on the surface of a preferably thin felt-tip-marker template — a tin plate with slotted window in it the size of the blade. Before clipping makes sense to be melted through the window a couple of holes, and then make slits along the contour of the blade. Note that to work tormaresca should be in a well ventilated area — it is best to have the window open. On the thus-prepared rotor blades folded back approximately 35°.

Hinge joints of the rotors have to ensure they are extremely smooth running, literally, from the slightest breeze. This can be done only with the help of ball bearings. For two-liter bottles are fine bearings with diameters of 18 (external) and 6 (inner) mm and a width of 6 mm.

For fixing bearings in the neck of the bottle need a case made of aluminum; in the neck it is fixed regular bottle with a stopper with a hole diameter of 8 mm. a Stepped roller, which rotate in the bearings and, accordingly, rotor — steel, on the platform of the bridge it is attached with a nut M6. To provide ease of rotation of the rotor, before installing bearings in case one should remove the grease (wash the bearings in kerosene) and apply engine oil intended for sewing machines.

The sea trials have correctly adjusted catamaran rotary engine spins easily and the little vessel, oriented sideways to the wind, quickly gaining speed, automatically maintaining a course relative to the wind direction. If the model is or uvarivaetsja it is necessary to shift the center of lateral resistance a permutation of the keel forward or backward.

It should be noted that the rotary catamaran can move not only the course galfvind when the wind is blowing exactly in the side but also a more complete or more severe courses. Although, of course, a classic catamaran with a sail capable of going several luff.

I. TEREKHOV