The method of making homemade water rockets is as follows:
Preparation materials: plastic bottle, double-sided tape, scissors, electrical tape , soft rubber stopper, knife.
The steps are as follows:
1. Make the wings. Use scissors to cut the X-ray film into 28 equal-sized rectangular trapezoids. The trapezoid measures 12 cm long and 6 cm high. The angle between the oblique waist and the long base is approximately 45 degrees. Cut 4 more trapezoids with the same specifications as above but 8cm high, with connected short bases and two overlapping sides, to use as the surface of the wings. Use double-sided tape to stick 7 small trapezoids firmly into a thick trapezoid, making it straight and flat, then wrap it tightly with a large double-sided trapezoid and stick it firmly.
To make the thick surface of the wing flat, you canuse scissors or a knife to straighten it, then seal the thick wing surface with insulating glue. Finally, bend the extensions on both sides of the wing outward 90 degrees. In this way, the remaining X-rays are transformed into three wings according to the above method.
2. Production of the body. Take a Jianlibao bottle with a natural curved head. It can be used as a rocket head to reduce air resistance. Cut it crosswise 11 cm from the lower end. Use insulating glue to glue the part with the neck of the bottle to the bottom of another bottle. . Use insulating glue to wrap a few more turns around the joint to secure it.
3. Production of air plugs. Take a No. 4 soft rubber plug, use a drilling tool to make a straight hole slightly smaller than the valve core sleeve in the middle of the bottom of the rubber plug,then use a knife to cut the thin end about 0.6cm; cut the valve core. The rings on the sleeve are sold at major hardware stores. Install the valve core from the thin end of the soft rubber plug upwards, put on a similar “ring” and tighten the screws, just a little. . Finally, use a sharpening stone to grind the air plug into a cylinder until it can fit completely into the mouth of the Coca-Cola bottle or is slightly tight. Install the valve core and it can be used.
4. Production of cannon heads. Take a #3 soft rubber stopper and use a knife to sharpen it and make it smooth.
5. Assemble the wings. Take a bottle of Jianlibao and cut out a cylinder with two connected sides slightly longer than the length of the wings. Then use transparent glue and insulating glue to glue the four wings together.four equal parts. Finally, place the cylinder with the wing stuck on it on the bottom of the water rocket so that it is level with the mouth of the bottle. This is not necessarily the best position. You can adjust it up and down during flight practice to find. and wrap it with insulating glue to tighten it.
Configuration problems with homemade electric motors and hydroelectric generators. Waiting online. Help me. High school student. . .
Yes. But what type of waterfall “filter” are you talking about? Let's briefly talk about the calculation of the yield (power), N=8.5QH, that is to say that its treatment is equal to the flow rate (cubic meter/second) multiplied by the water height (meters) then multiplied by 8 .5 to get her out. For example: the height difference between the upstream water surface and the downstream water surface of your hometown waterfall is 30 meters, the water flow rate is 0,005 cubic meter/second (5 liters), the coefficient is 0.85, calculation: 0.85*0.005*30=0.1275 (kilowatt), 15 can be used with current energy-saving lamps of 8 watts.
A 2.2M waterfall with a maximum water height of 2.2M. Take 2M for calculation, and the flow rate is 1L/S. Gravitational potential energy T=mgh, P=mgh/t=1000*10*2=20000J/s=20000/3.6=5.5KW
The efficiency of the original owner's homemade turbine will not exceed not 50% because that’s too small .
The motor efficiency will not exceed 85%
The power is therefore conservatively estimated at around 2 kW.
Since the water level is too low, the poster needs an axial flow vane turbine, and he can make one himself. Next, engage the gearbox at high speed. This can achieve higher efficiency.
As the power is too low, a 3 kW DC motor can be used with a relative structurement simple, then an inverter can be added.