INTRODUCTION:

The paper deals with the generation of electricity using hybrid method through road speed breakers. When vehicle is in motion, it produces various forms of energy. For instance, friction between vehicle wheels and road produces heat energy. The working principle of this proposed idea is the conversion of potential energy to electrical energy. When a vehicle going upon a speed breaker the potential energy generated by a vehicle is converted into kinetic energy.

PRINCIPLE OF OPERATION:

When the vehicle moves over the inclined plates, it gains height resulting in increase in potential energy. This energy is wasted in the conventional rumble strip. In order to harness the energy a cylindrical rod is fixed at one end with inclined plates and the other end with the rectangular bar. When the inclined plate moves down due to weight of the vehicle, the cylindrical rod is pushed down. The crank shaft mechanism is used to convert this potential energy to mechanical energy. The output of this shaft is coupled with a dynamo to convert this kinetic energy into electrical energy.

Piezoelectric [1, 2] and hydraulic system is added to the above setup to build a Hybrid system in production of electrical energy.

LITERATURE SURVEY:

Shad Roundy (2005) describes about the significance of the vibration-based energy produced. There has been a significant increase in the research on vibration-basedenergy harvesting in recent years.

Henry A. Sodano et al., (2005) explained about the concept of capturing the normally lost energy surroundinga system and converting it into electrical energythat can be used to extend the lifetime of that system’s power supply or possibly provide an endlesssupply of energy to an electronic device hascaptivated many researchers and has brought forth a growingamount of attention to power harvesting.

H. A. Sodano et al., (2005) explains about the use of this piezoelectric material (PZT) to produce electrical energy. It can be used as mechanisms to transfer mechanical energy, usually ambient vibration, into electrical energy that can be stored and used to power other devices. With the recent advances in wireless and micro-electro-mechanical-systems (MEMS) technology, sensors can be placed in exotic and remote locations. As these devices are wireless it becomes necessary that they have their own power supply.

Emílio C. N. Silva(2009) tells about a recently published paper, in which Zheng et al. (Struct Multidisc Optim 38:17–23, 2009) presented a topology optimization formulation for the design of energy harvesting devices considering the maximization of a predefined energy conversion factor. Their motivation was based on the observed trend of using piezoelectric effects to build energy harvesting devices or to harvest electrical energy from ambient vibrations. This discussion addresses some unclear points in the mentioned work.

Bin Zheng et al.,(2008) describes the energy harvesting devices based on the piezoelectric effect that converts ambient energy to electric energy is a very attractive energy source for remote sensors and embedded devices.. In this paper, both elastic materials as well as piezoelectric materials are considered for the design of energy harvesting devices under the topology optimization formulation. The objective function for this study is to maximize the energy conversion factor. The sensitivities of both stored strain energy and electrical energy are derived by the adjoin method. Examples of energy harvesting devices are presented and discussed using the proposed method.

MECHANICAL SYSTEM:

A crank is an arm attached at right angles to rotating shaft by which reciprocating motion imparted to or received from the shaft. It is used to change circular into reciprocating motion, or reciprocating into circular motion. The arm may be a bent portion of the shaft, or a separate arm attached to it. Attached to the end of the crank by a pivot is a rod, usually called a connecting rod.

The end of the rod attached to the crank moves in a circular motion, while the other end is usually constrained to move in a linear sliding motion, in and out.

Fig.1 Slider crank mechanism

A slider crank mechanism has been constructed and operated for the purpose of investigating steady state rod bending vibration induced by a very high speed crank. Features include a combination flywheel and adjustable length crank, a thin aluminum connecting rod, and a piston sliding on steel rod slide axes. A strain gauge on the rod and magnetic pickup on the crank sensed rod strain and crank speed, respectively.

For this system configuration, experimental results are categorized as small, intermediate and large crank length response. Small and intermediate cranks response was amplified due to a large super harmonic component of twice the crank speed frequency and at crank speeds near 1/2 the first natural frequency of the rod.

Beyond that speed, period doubling occurred over a range of speeds for intermediate length cranks. The occurrence of period doubling was experimentally sudden and audibly noticeable, and characterized by the onset of frequency components of 1/2, 3/2, 5/2, and 7/2 times the crank speed. For large crank sizes of 0.5, 1, and 2 inches an amplified response also appeared in each at a certain speed, but at speeds lower than in the small and intermediate crank cases. Larger cranks required more frequency components to describe the response than smaller cranks.

EXPERIMENTAL SETUP:

The same can be carried out experimentally by the following methods: Two plates are fixed at an angle of 45˚ on the road. Then a top cylindrical rod which is made of mild steel is placed at bottom of the inclined plates, fixed at both an ends. A rectangular bar is placed at bottom of the top cylindrical rod, where the one end of the top cylindrical rod is fixed. In a rectangular bar, one end of the open coil helical spring is fixed to the rectangular bar and the other end of the spring is fixed to the piston head of the crank arrangement.

Then the output of the shaft is coupled with dynamo. At the both side of the rectangular bar piezoelectric material^[7] is placed. It is to convert the mechanical energy to electrical energy. The other possible way is to use hydraulic.

The hydraulic cylinders are placed at the both ends of the rectangular bar. Turbines are placed below the hydraulic cylinder. Then at the end, a reservoir is placed to collect the fluid and to circulate the fluid to the cylinders. Refer Fig.2. Layout diagram of the setup.

WORKING PRINCIPLE:

This is the simple energy conversion from Mechanical energy into Electrical energy. To generate electricity using the vehicle moment as input. When the vehicle moves over the speed breaker the potential energy will be converted into mechanical energy. The top cylindrical rod which is fixed at both the ends will be pushed down by the vehicle load, when the force exerted on the rod will push down the rectangular bar.

Then, there will be a simultaneous process takes place by the crank mechanism, piezoelectric and hydraulic process. The rectangular bar will push the spring which is connected to the piston and crank arrangement, and then the output of the shaft is coupled with dynamo. By the way, some mechanical stress is induced to the piezoelectric material to generate current.

Fig.2 Layout diagram

Fig.3 Top plate setup

Fig.4 Crank case setup

Piezoelectric material can with stand some certain force ^[9], if it is beyond the limited force it breaks. So we are using closed coil helical springs which can with stand the force to prevent the breakage of the material. Then we are using hydraulic system, when the force is applied the piston pushes the fluid (water 75% and glycol 25%) down. The fluid flow through the hose and it will allow rotating the turbine.

The output of the shaft is coupled with dynamo. After, the fluid passes through the turbine it will be collected in the reservoir. Thus the fluid will be circulated. After the vehicle passes over the speed breaker, everything will come back to its original position.

In future, Experimental responses can be correlated with computer simulations of a one mode nonlinear ordinary and differential equation model, and over a wide range of speeds and for a representative of a small, intermediate and large crank length.

DESIGN CALCULATION:

1 Design procedure of spring:

1.1 Solid length:

Ls = n’d

n’ = no. of coils

dsp = dia of wire (2.6 mm)

Ls = 16 * 2.6 mm

Ls = 41.6 mm

1.2 Free length:

Lf = Solid length + Maximum compression + Clearance b/w adjacent coils.

= n’d + δmax + 0.15 δmax

= 41.6 + 100 +0.15 * 100

Lf= 156.6 mm

1.3 Spring Index:

C = Dsp/dsp

Where,

Dsp = 30 mm

dsp = 2.6 mm

C = 30/2.6

C = 11.5 mm

1.4 Pitch:

P = free length/n’ -1

= 156.6/ (16 – 1)

P = 10.44 mm

2 Design procedure of Top – cylindrical rod:

Pc = 175 * Fos (6)

Pc = 1050 kg

Assume C45 steel:

бc = 63 – 71 kgf/ cm2

c = 1/7500 (constant)

Lcy = 30 cm (fix)

r = d/2

Pc = a. бc / 1 + c (Lcy/r) 2

= л/4 * d2 * бc / 1 + c (L2cy/(d/2)2)

1050 = [(л/4*d2*65)/1 + (1/7500)*302/ (d2/4)]

1050 (1 + 1.33*10-4*(302/d2/4)) = 51.05 d2

1050 + 502.74/d2 =51.05 d2

d cy= 4.56 cm

3 Design procedure of Flat plate (fixed at one end):

Assume Lfp = 30 cm

bfp = 30 cm

Assumed,

бb = 400 kgf / cm2

Section modulus, z = bfp*t2/6

Bending moment, M = wLfp = 1050*30

M = 31500 kgf*cm

бb = M/2

400 = 31500/(5*t2)

t = 3.968

t fp≈ 4 cm

4 Design procedure of Rectangular bar:

Assume Lrec =50 cm

бb = My/I

M = wL/4

= (1050*50)/40

Mrect = 13125 kgf*cm

y = t/2

I = bt3/12

Assume b =3t

Assume бb = 400 kgf/cm2

400 = [(13125*t/2)/3t*t3/12]

= [(13125*t/2)/3t4/12]

400 = 13125*6/3t3

1200t3 = 78750

Trect= 4.0335 cm

5 Design procedures of Impeller/ Turbine:

Dimp = 0.5 m

ν = лDN/60

1.51 = (л*0.5*N)/60

90.6 = л*0.5*N

N = 57.67 rpm

6 Design procedure of Hydraulic Cylinder:

Pc = 87.5*6 = 525 kg

Pc = [(a* бc)/1 + c (Lhy/r) 2]

= (л/4*d2* бc)/1 + c (Lhy/r) 2

525 = [(л/4*d2*65)/(1/7500)* (Lhy/d/4) 2]

525 (1 + 1.33*10-4*302/ (d2/4)) =51.05dhy 2

525 + 251.37/d2 = 51.05dhy 2

d hy= 3.27cm

7 Calculations for Pressure:

Pressure = load/area

Area = ½*л*(9*10-2)2

= 0.02544/2

= 0.0127kg/m2

Pressure = 0.0127kg/m2

8 Calculations for Power:

P = 2л*N*T/60

Where, N = Generator Rpm

T = torque produce by crank

P = Power

tss = 40 - 50

T = л/16*tss*d3

= л/16*40*33

T = 212.05Nm

P = (2л*1500*212.05)/60

= 33308.7w

P = 33 kW

9 Calculation of Displacement of the Fluid:

Diameter of the plate, d = 18cm

Radius = 9cm

Time = 2.5 sec

1cm = 9/2.5*10-2 sec

V = 0.036 m/s

Q = a*v

= л/4*d2*v

d- Diameter of the cylinder

= л/4*(54.5*10-2)2*0.036

Q = 8.398*10-3 m3/s

10 Calculation of Velocity of the fluid:

Q = Displacement of the fluid

Q = A*v

8.398*10-3 = л/4*d2*v

V = 8.398*10-3 / (л/4*20*10-2)2

V = 0.2673 m/s

11 Calculation of Nozzle pressure:

Nozzle pressure, pr = F/A

Where, F =50 kg

D =20 mm (nozzle diameter)

= 50/ л/4*d2

= 50/ л/4*202

P = 0.159 bar

12 Calculation of Torque produced in Turbine:

T = F*r

= 45*5/2*10-2

= (45*9.81)*5/2*10-2

T = 11 N-m

13 Calculation of Power produced through Turbine:

P = (F*distance)/time

Distance = 2л*r/2

= 2 л*5/2

= 15.70cm

Distance = 0.1570m

P = 45*0.1570/1

P = 7.065 watt

CONCLUSION:

An approach of Power Generation using hybrid method through speed breaker has been suggested theoretically, analytically and experimentally. In future, the same can be used for the commercial purpose in two way roads as well and voltage can be produced from the crank mechanism, impeller and piezoelectric material.

REFERENCES:

1 T. H. Ng, W. H. Liao(2005)- Sensitivity Analysis and Energy Harvesting for a Self-Powered Piezoelectric Sensor; Journal of Intelligent Material Systems and Structures, Vol. 16, No. 10, 785-797

2 Shad Roundy (2005); On the Effectiveness of Vibration-based Energy Harvesting; Journal of Intelligent Material Systems and Structures, Vol. 16, No. 10, 809-823

3 Henry A. Sodano, ,Daniel J. Inman And Gyuhae Park (2005) - Generation And Storage Of Electricity From Power Harvesting Devices; Journal Of Intelligent Material Systems And Structures, Vol. 16, No. 1, 67-75

4 H. A. Sodano, G. Park and D. J. Inman (2005) - Estimation of Electric Charge Output for Piezoelectric Energy Harvesting; Journal of Intelligent Material Systems and Structures, Vol. 16, No. 10, 799-807

5 Bin Zheng, Ching-Jui Chang and Hae Chang Gea (2009)-Topology optimization of energy harvesting devices using piezoelectric materials; Structural and Multidisciplinary Optimization; Volume 38, Number 1

6 Emílio C. N. Silva(2009) tells about a recently published paper, in which Zheng et al. (Struct Multidisc Optim 38:17–23, 2009)

7 H. H. Law, P. L. Rossiter, G. P. Simon And L. L. Koss (1996) - Characterization Of Mechanical Vibration Damping By Piezoelectric Materials ; Journal of Sound And Vibration; Volume 197, Issue 4, Pages 489-513.

8 Dongna Shen, Song-Yul Choe, Dong-Joo Kim (1999) -Comparison of Piezoelectric Materials for Vibration Energy Conversion Devices; Materials Research Society Symposium Proceedings; Publisher Warrendale, Pa.; VOL 966, pages 162-167

9 Mikio Umeda, Kentaro Nakamura and Sadayuki Ueha(1997) - Energy Storage Characteristics of a Piezo-Generator using Impact Induced Vibration; Jpn. J. Appl. Phys. 36 pp. 3146-3151

10 Emílio C. N. Silva(2009) - Comment on “Topology optimization of energy harvesting devices using piezoelectric materials- Discussion;” Escola Politécnica da Universidade de São Paulo Volume 39, Number 3 pgs 337-338.

Received on 27.07.2017 Accepted on 15.09.2017

Research J. Engineering and Tech. 2017; 8(4):351-355.

DOI: 10.5958/2321-581X.2017.00061.7