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Balloon Powered Sprint Car

AUTHORS' NAMES (Capital, 12pt Times New Roman, centered)

Department (12pt Times New Roman, centered)

University (12pt Times New Roman, centered)

Address (12pt Times New Roman, centered)COUNTRY (Capital, 12pt Times New Roman, centered)

youremailaccount@xxx.xxx.xx http://www.yourwebaddress.xx (12pt Times New Roman, centered)

Abstract: - The research is about designing a sprint car to race on a 4 m long track and the car must stop within1m of the finish line. The sprint car is also required to carry an open container filled with water and the water

must not be spilt during the race. The car will race in three rounds. The sprint car can use any sort ofmechanisms in order to move the car.

1 IntroductionEach group has been given different mechanism tomove the car. Any specific design for the sprint car

can be designed but the mechanism of moving thecar cannot be changed. Our group, Zenith is

required to design a balloon powered car. So,balloons are required in order to move the car. Theballoons will be filled with certain volume of the air

and will be tested on how volume of the air relateswith the distance the sprint car travels. The law

being used in this mechanism is Newtons third law

of motion which states To every action there is anequal and opposite reaction.

The air moves out of the balloon and flow in onedirection and the car moves in the oppositedirection. The air acts as a medium to accelerate thesprint car to reach the finish line. However, airmoves out of the balloon in one direction is only anassumption because it is actually erratic. When theballoon is released, it will have some rotation andforce exerted by the air on the balloon will keepchanging the direction.

The energy released by the balloon air flow will bedivided into two main compartments; the energywhich moves the car and the energy which movesthe air. The input energy given to the car wouldmainly waste in two ways (other than the kineticenergy of the air). Initially, a fraction of the energywill be lost during the inflation process due to theballoons plastic deformation. This phenomenon isentitled as the Moulins Effect. Note that a filledand emptied balloon will be larger than the initial

balloon. This means that a part of the energy givento a balloon while inflation will be used to deform

the rubber material, which is not given back when itdeflates. ( Parham & Reza & Hossein , 2011)

The second form of energy loss occurs when thefluid is in rapid motion during deflation.This energy loss is widely known as Head Loss,and has two main factors: Head Loss caused by theviscous friction forces with the inner membrane ofthe balloon, and the head loss resulted by theturbulent motion which arises from the highvelocity. Both of these factors are proportional to

the velocity square and the proportions are functionsofthe systems size and geometrical properties (inour case, the head loss coefficient alters during timeand cannot be considered as a constant.) ( Parham

& Reza & Hossein , 2011)

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2 Problem FormulationThere are some problems regarding the mechanismworks. The problems are needed to be solved inorder to make sure the balloon powered car functioneffectively.

2.1 Volume of airVolume of air is hard to measure accurately sincewe are lack of volume measuring instruments.

Volume of air plays important role in this research.The main element to move the car is by controllingthe volume of air. In our research, volume of air actsas manipulated variable while the distance the cartravels acts as responding variable.

2.1.1 Flow out of the air

Flow out of the air is also crucial in our research

since it also decides on the distance the car travels.When the flow of air is not constant, the movementof the car will be affected and thus make it difficultto make relationship between volume of air and

distance of the car travels.

2.1.2 Volume loss

Since the air molecule is so small, when the balloonis inflated, there will be a little bit volume loss due

to the way the balloon is being held. So, the volumeof air in the balloon will not be the same as

calculated since there is already volume loss before

the volume of air in the balloon is released.

2.2 Density of carDensity of car is also important regarding ourresearch. As we all know, moving an object usingair is quite difficult compared to other mechanisms.It is possible but the volume of air must be high andthe density of the car must be as lightweight as

possible. Increases of 1 kg of the mass of car mightresult in huge difference in the volume of air needed

to attain same distance of the car travels.

3 Problem SolutionIn order to control the volume of air, the balloon ismeasured by using a thread. The thread is later

being measured by a ruler. So, thread having thesame length as the balloons circumference. From

the circumference, the radius and the diameter of theballoon can be calculated by the formula;

Knowing the radius, the volume can be calculatedby equation of volume of sphere as balloon can beconsidered as sphere.

The volume now can be used to relate with thedistance travelled by the sprint car.

The flow out of the air is erratic since the air movesin different directions. To minimize the changes indirection and to make sure it moves in one direction,we made a polystyrene holder for the balloon. 2polystyrene holders are attached to the sprint car andthe flow out of the air will only focus in one

direction or at least minimize the changing of

directions.

Volume loss is quite difficult to control since airmolecule is so tiny. The best thing to overcome

volume loss is by the way of holding the balloon.The balloon must be held tightly and the experimentmust be done as quickly as possible to reduce theamount of volume loss.

Since the air is not a really suitable to act asmechanism to move the car, the density of the car is

highly considered to make sure the performance of

balloon car is at the best level. The car is needed tobe as lightweight as possible. The materials to build

the car play the part in this issue. So, the bestmaterials that we chose are plastic and polystyrene.

The wheels of the car are made of plastic. The baseof the car also made of plastic while the cup holder

and polystyrene holder for the balloon are made ofpolystyrene.

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4 ConclusionAs a conclusion, balloon powered car is possible tomove along the track by using air as the mechanismto provide the acceleration and momentum of thecar. So, it is not weird that some universities made

balloon powered car racing as one of course workactivities.

However, the velocity of balloon powered car ismuch less compared to some other electrical, elastic

band cars. It is mostly because of the operation ofthe car. The balloon powered car might be fast but itrequires many balloons. Since it is not suitable toplace many balloons in just small A4 sized car, thevelocity of our balloon powered car is quite average.

By measuring volume of air and the distance

travelled by the car, it can be concluded that volumeof air is important in deciding on how far the carwill travel. The higher the volume of air, the longerthe distance the car travels. The number of balloonsattached to the car also can help to increase thedistance the car travels. It is because the moreballoons used, the higher the total volume since thetotal volume is the additional of all balloonsattached to the car. There is no maximum for thetotal distance travelled by the car, unless amaximum possible volume for the balloon exists.

The movement of the car mostly influenced by thedirection of air released from the balloon.Sometimes, the direction of air released is inclinedto the left or right side and make the movement ofthe car is not stable. It also reduces the accelerationof the car. So, the balloon holder is the best way to

overcome this problem.

One of the things worked well in our research iswhen we decided to change the angle the balloonface to the surface. We made the polystyrene holder

inclined to the bottom in order to increase theacceleration and momentum of the car. The angle

changed the result dramatically, it was about 1mlonger the distance compared to normal angle.

If we can design a smaller car, we could increase thevelocity of the car. The lighter the car, the faster thecar will move if the volume of the balloon is keptconstant. Since the size of the car is a controlled

variable in our research, we cannot reduce the sizeof the car.

Besides, if we were given the chance to do theproject again, we will change the dynamics of the

body so the air would pass right through without

putting too much drag on the car. One more thingwe can change is the wheels, making wheels usingCDs will work better because they were thin andexperience less friction.

References:[1]

Nobaria, P. Z., Namin, R. M., & Azizinaghsh,

H. (2011). Efficiency evaluations of a balloon

powered car.