Instrumentation for Control System 2

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Control System 2

Instrumentation for Control System

Title:

The Radiator System for Vehicle

Member of Group:

MOHD ZHARIF BIN OTHMAN [2006874765]

HAIRI ANWAR BIN AMINUDDIN [2006874852]

AHMAD AZKA BIN HJ MOHD ZAIN [2006686484]

Group:

EEB6R1

Lecturers Name: EN. ADIZUL AHMAD


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Title: The Radiator System for Vehicle

1.0 Introduction

Inside the car's engine, fuel is constantly burning. A lot of the heat from this combustion

goes right out the exhaust system, but some of it soaks into the engine, heating it up. Theengine runs best when its coolant is about 200 degrees Fahrenheit (93 degrees Celsius). At

this temperature:

The combustion chamber is hot enough to completely vaporize the fuel, providing

better combustion and reducing emissions.

The oil used to lubricate the engine has a lower viscosity (it is thinner), so the engine

parts move more freely and the engine wastes less power moving its own components

around.

Metal parts wear less.

Although gasoline engines have improved a lot, they are still not very efficient at turningchemical energy into mechanical power. Most of the energy in the gasoline (perhaps 70%) is

converted into heat, and it is the job of the cooling system to take care of that heat. In fact, the

cooling system on a car driving down the freeway dissipates enough heat to heat two average-

sized houses! The primary job of the cooling system is to keep the engine from overheating

by transferring this heat to the air, but the cooling system also has several other important

jobs[1].

The car engine runs best at a fairly high temperature. When the engine is cold,

components wear out faster, and the engine is less efficient and emits more pollution. So

another important job of the cooling system is to allow the engine to heat up as quickly as

possible, and then to keep the engine at a constant temperature. The radiator system is one of

the main systems in the car.

Figure 1: The whole system of radiator for vehicle


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2.0 Schematic Diagram

3.0 Block Diagram

Input Element

Radiator

System

Initial

Temperature

Figure

Figure 3:

Control Element

Process Element

Thermostate

Block

Cooling

Head

Cooling

Water

Pump

2: The schematic of the cooling of the vehicl

he block diagram of the cooling of the vehi

Output Element

Constant

Temperature

e

le


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4.0 Principle of Operation

There are four elements involve in this radiator system. There are consists of control

elements, process elements, input and output elements.

4.1 Input Element

Once the car engine start, the initial temperature will be determined. The cooling

system on liquid-cooled cars circulates a fluid through pipes and passageways in the engine.

As this liquid passes through the hot engine it absorbs heat, cooling the engine. After the fluid

leaves the engine, it passes through a heat exchanger, or radiator, which transfers the heat

from the fluid to the air blowing through the exchanger.

4.2 Process Element

4.2.1 Plumbing

The cooling system in car has a lot of plumbing. The process to cool down the engine

start with the pump sends the fluid into the engine block, where it makes its way through

passages in the engine around the cylinders. Then it returns through the cylinder head of the

engine. The thermostat is located where the fluid leaves the engine. The plumbing around the

thermostat sends the fluid back to the pump directly if the thermostat is closed. If it is open,

the fluid goes through the radiator first and then back to the pump. There is also a separate

circuit for the heating system. This circuit takes fluid from the cylinder head and passes it

through a heater core and then back to the pump.

4.2.2 Fluid

Cars operate in a wide variety of temperatures, from well below freezing to well over

100 F (38 C). So whatever fluid is used to cool the engine has to have a very low freezing

point, a high boiling point, and it has to have the capacity to hold a lot of heat.

Water is one of the most effective fluids for holding heat, but water freezes at too high

a temperature to be used in car engines. The fluid that most cars use is a mixture of water and

ethylene glycol (C2H6O2), also known as antifreeze. By adding ethylene glycol to water, theboiling and freezing points are improved significantly.

Pure Water50/50

C2H6O2/Water

70/30

C2H6O2/Water

Freezing Point 0 C / 32 F -37 C / -35 F -55 C / -67 F

Boiling Point 100 C / 212 F 106 C / 223 F 113 C / 235 F

Table 1: The different temperature between pure water and antifreeze water


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The temperature of the coolant can sometimes reach 250 to 275 F (121 to 135 C).

Even with ethylene glycol added, these temperatures would boil the coolant, so something

additional must be done to raise its boiling point.

The cooling system uses pressure to further raise the boiling point of the coolant. Just

as the boiling temperature of water is higher in a pressure cooker, the boiling temperature ofcoolant is higher if you pressurize the system. Most cars have a pressure limit of 14 to 15

pounds per square inch (psi), which raises the boiling point another 45 F (25 C) so the coolant

can withstand the high temperatures. Antifreeze also contains additives to resist corrosion.

4.2.3 Water Pump

A water pump is a simple device that will keep the coolant moving as long as theengine is running. It is usually mounted on the front of the engine and turns whenever the

engine is running. The water pump is driven by the engine through one of the following. The

water pump moves the water from the engine to the thermostat assembly. If the thermostat is

open, the water passes through the radiator and back into the engine. Whether the thermostat

is open or closed, the pump also circulates water through the heater core and back into the

engine.

Figure 4: The Water Pump


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4.3 Control Element

4.3.1 Thermostat

The thermostat's main

the engine at a constant temp

through the radiator. At low t

all of the coolant is circulated

the flow of coolant throughou

the amount of coolant movin

from overheating. And seco

temperature is kept within a

within this narrow band of te

Once the temperaturethermostat starts to open, allo

reaches 200 to 218 F (93 - 103

The secret of the ther

device. This cylinder is fille

thermostats open at different

the valve presses into this waout of the cylinder and openi

for greenhouse vents and skyl

Fi

job is to allow the engine to heat up quickl

rature. It does this by regulating the amoun

emperatures, the outlet to the radiator is co

back through the engine. The thermostat in

t the system. This is important for two reaso

through the cooling system to help keep t

nd, it controls the flow in such a way

arrow margin. The vehicles engine operate

perature regulation [3].

of the coolant rises to between 180 and 195ing fluid to flow through the radiator. By t

C), the thermostat is open all the way.

ostat lies in the small cylinder located on th

d with a wax that begins to melt at arou

emperatures, but 180 F is a common one).

. When the wax melts, it expands significang the valve. This same technique is used i

ghts. In these devices, the wax melts at a lo

ure 5: The Thermostat

, and then to keep

of water that goes

pletely blocked --

a vehicle regulates

ns. First, it controls

e vehicles engine

that the operating

at peak efficiency

F (82 - 91 C), thehe time the coolant

engine-side of the

d 180 F (different

A rod connected to

ly, pushing the rodautomatic openers

er temperature.


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4.3.2 Radiator Fan

Mounted on th

two electric fans insid

air flow. These fans a

vehicle is going slowworking, every time y

On older systems, the

spin whenever the eng

electric motor. In the

stop and go driving, t

the fan faster which

malfunctioning electri

more heat in the radiat

The electric fans are

monitors engine temcomputer determines

additional air flow thr

If the car has air cond

normal radiator. This

needs to be cooled by

more about the air co

Conditioning. As lon

fan running, even if t

flow through the air co

the air entering the int

back of the radiator on the side closest to t

e a housing that is designed to protect finge

e there to keep the air flow going through th

or is stopped with the engine running. Ifou came to a stop, the engine temperature

fan was connected to the front of the wat

ne was running because it was driven by a f

e cases, if a driver would notice the engine

e driver might put the car in neutral and re

helped cool the engine. Racing the engin

fan would only make things worse becaus

or with no fan to cool it off.

controlled by the vehicle's computer. A

erature and sends this information to tif the fan should be turned on and actuat

ugh the radiator is necessary.

itioning, there is an additional radiator mou

"radiator" is called the air conditioner co

he air flow entering the engine compartmen

ditioning condenser by going to our article

as the air conditioning is turned on, the s

e engine is not running hot. This is becau

nditioning condenser, the air conditioner wil

rior

Figure 5: Radiator fan

he engine is one or

rs and to direct the

e radiator while the

these fans stoppedould begin rising.

r pump and would

n belt instead of an

begin to run hot in

the engine to turn

e on a car with a

you are producing

temperature sensor

e computer. Thees the fan relay if

nted in front of the

denser, which also

. You can find out

on Automotive Air

stem will keep the

e if there is no air

not be able to cool


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Figure 6: Radiator

4.3.3 Radiator

A radiator is a type of heat exchanger. The radiator's main function is to transfer the

heat generated in the engine to the surrounding atmosphere. It contains a large quantity of

small water passage tubes and interconnecting fins, and as hot water passes through the tubes,

some of the heat is radiated into the air passing between the tubes. A secondary purpose of the

radiator is to provide storage for the needed volume of water required to cool the engine in

question.

Most modern cars use aluminum radiators. These radiators are made by brazing thin

aluminum fins to flattened aluminum tubes. The coolant flows from the inlet to the outlet

through many tubes mounted in a parallel arrangement. The fins conduct the heat from the

tubes and transfer it to the air flowing through the radiator.

The tubes sometimes have a type of fin inserted into them called a turbulator, which

increases the turbulence of the fluid flowing through the tubes. If the fluid flowed verysmoothly through the tubes, only the fluid actually touching the tubes would be cooled

directly. The amount of heat transferred to the tubes from the fluid running through them

depends on the difference in temperature between the tube and the fluid touching it. So if the

fluid that is in contact with the tube cools down quickly, less heat will be transferred. By

creating turbulence inside the tube, all of the fluid mixes together, keeping the temperature of

the fluid touching the tubes up so that more heat can be extracted, and all of the fluid inside

the tube is used effectively.


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4.3.4 Heater Core

The hot coolant is also

This is a simple and straightsmall version of a radiator, co

hose brings hot coolant from

coolant to the top of the engi

block the flow of coolant into

A fan, called a blowe

heater ducts to the interior o

that mixes cool outside air,

through the heater core. Thi

coming into the interior. Oth

the floor, the defroster ductslocated in the instrument pane

used to provide heat to the interior of the ve

forward system that includes a heater core,nnected to the cooling system with a pair of

he water pump to the heater core and the ot

e. There is usually a heater control valve in

the heater core when maximum air condition

, draws air through the heater core and di

the car. Temperature of the heat is regulat

or sometimes air conditioned air with the

s blend door allows you to control the te

er doors allow you to direct the warm air t

at the base of the windshield, and the airl.

Figure 7: heater core

hicle when needed.

which looks like arubber hoses. One

er hose returns the

one of the hoses to

ing is called for.

ects it through the

ed by a blend door

heated air coming

perature of the air

rough the ducts on

conditioning ducts


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5.0 Objective of Control

Once the engine operates, the heat will be produced. Then, the temperature will

increase due to combustion in the engine block. The chemical energy will be

converted into mechanical energy. The thermostat is a component to control the

coolant that circulated around the block engine. The heat from the engine block will be

spread and transfer to the coolant [2]. The radiators function here is to remove the

heat in the water to the air. The temperature of the water will be maintained at the

constant temperature.

6.0 Conclusion

As a conclusion, we know that radiator is the closed system. The operation is

clearly explained in this report. The temperature is expected to be constant in order to

maintain the operation of the engine. The combustion will produce and spread more

heat. If the cooling system is not there, the engine will not functioning properly.

7.0 References

[1] http://auto.howstuffworks.com/cooling-system.htm

[2] http://www.car-stuff.com/radiator.htm

[3] http://www.streetdirectory.net.my/travel_guide/12348. html

Instrumentation for Control System 2

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