2011年度香港理工大學(xué)交換學(xué)生課程設(shè)計(jì)性實(shí)驗(yàn)報(bào)告

1、風(fēng)力發(fā)電機(jī)製作及相關(guān)物理計(jì)算MAKING OF WIND TURBINEAND RELATED CALCULATION,香港理工大學(xué)應(yīng)用物理學(xué)系學(xué)生翟振亨HKPUApplied Physics StudentChka Chun Hang,目錄,引言理論發(fā)電機(jī)的設(shè)計(jì)製作過(guò)程相關(guān)計(jì)算演示,Where do winds come from?風(fēng)從哪裡來(lái)?,Because of the temperature dif

2、ferences(溫差) around the world,,Surface Wind,Convection updraft of rising warm Air,What is wind turbine(風(fēng)力發(fā)電機(jī))?,Wind’s kinetic energy(動(dòng)能) ->electrical energy(電能),,Theory理論,By Lenz’s Law (冷次定律) Induced current(

3、感生電流) opposes (對(duì)抗) the change of the magnetic force Heinrich Lenz 海因里希·冷次,,Theory理論,Theory理論,Induced emf-感生電壓,Where ,N is the number of turn of coil,B is the magnetic field strength(磁場(chǎng)

4、強(qiáng)度)A is the area(面積) of the coil,,,,,,,,,,,,Design-設(shè)計(jì),,Design-設(shè)計(jì) (3D View),,Design-設(shè)計(jì) (3D View),,Brace 支架,Design-設(shè)計(jì) (3D View),,Axle 軸,Design-設(shè)計(jì) (3D View),,Turbine 渦輪,Design-設(shè)計(jì) (3D View),,Rotor 轉(zhuǎn)片,Design-設(shè)計(jì) (3D View),,C

5、oil 電線圈,Design-設(shè)計(jì) (3D View),,Supporting Base支撐底部,Design-設(shè)計(jì) (3D View),,Magnet 磁鐵,Material-物料,Screw(螺絲) x 8Bearing(滾珠軸承)x 2Wooden borad(5”x10”) Wooden board(2”x10”)Copper wire(漆皮銅線) Chopstick(筷子) x 3Water bottle(水

6、樽)Magnet (磁石)x 4LED 燈x 1CD case x 1),Making Process-製作過(guò)程,1. Preparing the material,Making Process-製作過(guò)程,2.making the frame(骨架) and base,1,2,3,Making Process-製作過(guò)程,Finished product,Making Process-製作過(guò)程,3. Assembly(

7、集合) the CD case and the base,1,2,3,4,Making Process-製作過(guò)程,4. making the coil by the copper wire,Making Process-製作過(guò)程,5. assembly to the CD case,Making Process-製作過(guò)程,5. assembly to the CD case,Making Process-製作過(guò)程,6. making t

8、he rotor(轉(zhuǎn)片),Making Process-製作過(guò)程,6. making the rotor (轉(zhuǎn)片),1,3,2,Making Process-製作過(guò)程,7. making the turbine(渦輪),1,2,4,3,Making Process-製作過(guò)程,7. making the turbine (渦輪),5,6,7,Making Process-製作過(guò)程,8. assembly all the component

9、(部件),Final Product-製成品,Finish!!,,Calculation相關(guān)計(jì)算,Power(功率) of Wind turbine,kinetic energy of a mass in motions is:The power in the wind is given by the rate of change of energy:As mass flow rate is given by:,,,,,P

10、ower (功率) of Wind turbine,Also, the rate of change of distance is given by:we get:Hence, the power can be defined as:,,,,Power (功率) of Wind turbine,Power coefficient(功率系數(shù)),Cpmax = 0.59 Therefore, the extract

11、able power:,Picture captured from http://www.eoearth.org/article/Betz,_Albert,German physicist Albert Betz,No wind turbine can convert(轉(zhuǎn)換) more than 16/27 (59.3%) of the kinetic energy of the wind into mechanical energy

12、 turning a rotor.,,Power (功率) of Wind turbine,For this turbine,假設(shè) ,Power Coefficient(功率系數(shù)), Cp = 0.5Air density(密度), ρ = 1.23 kg/m3Area of blades(扇葉), A= 0.04*0.2 = 0.008 m2Wind speed(風(fēng)速), v = 20km/h = 5.56 m/se

13、c所以, P = ½*0.5*1.23*0.008*5.563 = 0.423 W,Induced voltage-感生電壓,Since, Thus,,,,,,,,,Induced voltage-感生電壓,Normally, an AA battery(電池) is having 1.5V,,,,,Applications(應(yīng)用),,Factor (影響因素),Factor(影響因素) of output