Temperature Sensing Instrument

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Mapua Institute Of Technology

School Of Mechanical & Manufacturing Engineering

Muralla St. Intramuros, Manila

REPORT NO. 2

Temperature Sensing Instrument

Name: TABUGADIR, Virgil Emilson A. Date of performance: 05/06/14

Student No.: 2010104641 Date of submission: 05/13/14

Course & Year: ME - 4

ENGR. IGMEDIO F. ISLA JR.

PROFESSOR


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TABLE OF CONTENTS

CONTENTS page number

OBJECTIVES

THEORIES/PRINCIPLES

DISCUSSION

FINAL DATA SHEET

SAMPLE PROBLEMS

REFERENCES

CONCLUSION

RECOMMENDATION

PRELIMINARY DATA SHEET


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DISCUSSION

Attempts of standardized temperature measurement have been reported

as early as 170 AD byClaudius Galenus.The modern scientific field has its

origins in the works by Florentine scientists in the 17th century. Early devices to

measure temperature were called thermoscopes.The first sealed thermometer

was constructed in 1641 by the Grand Duke of Toscani, Ferdinand II. The

development of today'sthermometers andtemperature scales began in the early

18th century, whenGabriel Fahrenheit adapted a thermometer using

mercury and a scale both developed by Ole Christensen Rmer. Fahrenheit's

scale is still in use, alongside theCelsius scale and theKelvin scale.

Temperature is a measure of the warmth or coldness of an object or

substance with reference to some standard value. The temperature of two

systems is the same when the systems are in thermal equilibrium

If we experiment further with more than two systems, we find that manysystems can be brought into thermal equilibrium with each other; thermalequilibrium does not depend on the kind of object used. Put more precisely,

The zeroth law of thermodynamics states that, if two systems are separately inthermal equilibrium with a third, then they must also be in thermal equilibriumwith each other,

It may be restated as follows:

If three or more systems are in thermal contact with each other and all inequilibrium together, then any two taken separately are in equilibrium with oneanother.

Now one of the three systems could be an instrument calibrated to measure the

temperature - i.e. a thermometer. When a calibrated thermometer is put in

thermal contact with a system and reaches thermal equilibrium, we then have a

quantitative measure of the temperature of the system.
http://en.wikipedia.org/wiki/Galenhttp://en.wikipedia.org/wiki/Thermoscopehttp://en.wikipedia.org/wiki/Thermometerhttp://en.wikipedia.org/wiki/Temperaturehttp://en.wikipedia.org/wiki/Gabriel_Fahrenheithttp://en.wikipedia.org/wiki/Mercury_(element)http://en.wikipedia.org/wiki/Ole_R%C3%B8merhttp://en.wikipedia.org/wiki/Celsiushttp://en.wikipedia.org/wiki/Kelvinhttp://en.wikipedia.org/wiki/Kelvinhttp://en.wikipedia.org/wiki/Celsiushttp://en.wikipedia.org/wiki/Ole_R%C3%B8merhttp://en.wikipedia.org/wiki/Mercury_(element)http://en.wikipedia.org/wiki/Gabriel_Fahrenheithttp://en.wikipedia.org/wiki/Temperaturehttp://en.wikipedia.org/wiki/Thermometerhttp://en.wikipedia.org/wiki/Thermoscopehttp://en.wikipedia.org/wiki/Galen


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THERMOMETER

A thermometer is an instrument that measures the temperature of a system in aquantitative way. The easiest way to do this is to find a substance having aproperty that changes in a regular way with its temperature. The most direct'regular' way is a linear one:

t(x) = ax + b,

where t is the temperature of the substance and changes as the property x ofthe substance changes. The constants a and b depend on the substance usedand may be evaluated by specifying two temperature points on the scale, suchas 32 for the freezing point of water and 212 for its boiling point.

For example, the element mercury is liquid in the temperature range of -38.9 Cto 356.7 C (we'll discuss the Celsius C scale later). As a liquid, mercuryexpands as it gets warmer, its expansion rate is linear and can be accuratelycalibrated.

Thermometers may be described as empirical or absolute. Absolute

thermometers are calibrated numerically by the thermodynamic absolute

temperature scale. Empirical thermometers are not in general necessarily in

exact agreement with absolute thermometers as to their numerical scalereadings, but to qualify as thermometers at all they must agree with absolute

thermometers and with each other in the following way: given any two bodies

isolated in their separate respective thermodynamic equilibrium states, all

thermometers agree as to which of the two has the higher temperature, or that

the two have equal temperatures. For any two empirical thermometers, this does

not require that the relation between their numerical scale readings be linear,

but it does require that relation to bestrictly monotonic.This is a fundamental

character of temperature and thermometers.

As it is customarily stated in textbooks, taken alone, the so-called "zeroth law ofthermodynamics"fails to deliver this information, but the statement of the zeroth

law of thermodynamics byJames Serrin in 1977, though rather mathematically

abstract, is more informative for thermometry: "Zeroth LawThere exists a

topological line which serves as a coordinate manifold of material behaviour.

The points of the manifold are called 'hotness levels', and is called the

'universal hotness manifold'."To this information there needs to be added a
http://en.wikipedia.org/wiki/Monotonic_functionhttp://en.wikipedia.org/wiki/Zeroth_law_of_thermodynamicshttp://en.wikipedia.org/wiki/Zeroth_law_of_thermodynamicshttp://en.wikipedia.org/wiki/James_Serrinhttp://en.wikipedia.org/wiki/James_Serrinhttp://en.wikipedia.org/wiki/Zeroth_law_of_thermodynamicshttp://en.wikipedia.org/wiki/Zeroth_law_of_thermodynamicshttp://en.wikipedia.org/wiki/Monotonic_function


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sense of greater hotness; this sense can be had, independently ofcalorimetry,

ofthermodynamics,and of properties of particular materials, fromWien's

displacement law ofthermal radiation:the temperature of a bath of thermal

radiation isproportional,by a universal constant, to the frequency of the

maximum of itsfrequency spectrum;this frequency is always positive, but canhave values thattend to zero.Another way of identifying hotter as opposed to

colder conditions is supplied by Planck's principle, that when a process of

isochoric adiabatic work is the sole means of change of internal energy of a

closed system, the final state of the system is never colder than the initial state;

except for phase changes with latent heat, it is hotter than the initial state.

There are several principles on which empirical thermometers are built, as listed

in the section of this article entitled "Primary and secondary thermometers".

Several such principles are essentially based on the constitutive relation between

the state of a suitably selected particular material and its temperature. Onlysome materials are suitable for this purpose, and they may be considered as

"thermometric materials". Radiometric thermometry, in contrast, can be only

very slightly dependent on the constitutive relations of materials. In a sense

then, radiometric thermometry might be thought of as "universal". This is

because it rests mainly on a universality character of thermodynamic equilibrium,

that it has the universal property of producingblackbody radiation.

Thermometers can be divided into two separate groups according to the level of

knowledge about the physical basis of the underlying thermodynamic laws and

quantities. For primary thermometers the measured property of matter is known

so well that temperature can be calculated without any unknown quantities.

Examples of these are thermometers based on the equation of state of a gas, on

thevelocity of sound in a gas, on the thermal noise,voltage orcurrent of an

electrical resistor, on blackbody radiation, and on the

angularanisotropy ofgamma ray emission of certainradioactivenuclei in

amagnetic field.Primary thermometers are relatively complex.

Secondary thermometers are most widely used because of their convenience.

Also, they are often much more sensitive than primary ones. For secondary

thermometers knowledge of the measured property is not sufficient to allow

direct calculation of temperature. They have to be calibrated against a primary

thermometer at least at one temperature or at a number of fixed temperatures.

Such fixed points, for example,triple points andsuperconducting transitions,

occur reproducibly at the same temperature.
http://en.wikipedia.org/wiki/Calorimetryhttp://en.wikipedia.org/wiki/Thermodynamicshttp://en.wikipedia.org/wiki/Wien%27s_displacement_law#Frequency-dependent_formulationhttp://en.wikipedia.org/wiki/Wien%27s_displacement_law#Frequency-dependent_formulationhttp://en.wikipedia.org/wiki/Thermal_radiationhttp://en.wikipedia.org/wiki/Proportionality_(mathematics)http://en.wikipedia.org/wiki/Frequency_spectrum#Lighthttp://en.wikipedia.org/wiki/Third_law_of_thermodynamicshttp://en.wikipedia.org/wiki/Blackbodyhttp://en.wikipedia.org/wiki/Velocityhttp://en.wikipedia.org/wiki/Voltagehttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Anisotropyhttp://en.wikipedia.org/wiki/Gamma_rayhttp://en.wikipedia.org/wiki/Radioactive_decayhttp://en.wikipedia.org/wiki/Atomic_nucleushttp://en.wikipedia.org/wiki/Magnetic_fieldhttp://en.wikipedia.org/wiki/Triple_pointhttp://en.wikipedia.org/wiki/Superconductivityhttp://en.wikipedia.org/wiki/Superconductivityhttp://en.wikipedia.org/wiki/Triple_pointhttp://en.wikipedia.org/wiki/Magnetic_fieldhttp://en.wikipedia.org/wiki/Atomic_nucleushttp://en.wikipedia.org/wiki/Radioactive_decayhttp://en.wikipedia.org/wiki/Gamma_rayhttp://en.wikipedia.org/wiki/Anisotropyhttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Voltagehttp://en.wikipedia.org/wiki/Velocityhttp://en.wikipedia.org/wiki/Blackbodyhttp://en.wikipedia.org/wiki/Third_law_of_thermodynamicshttp://en.wikipedia.org/wiki/Frequency_spectrum#Lighthttp://en.wikipedia.org/wiki/Proportionality_(mathematics)http://en.wikipedia.org/wiki/Thermal_radiationhttp://en.wikipedia.org/wiki/Wien%27s_displacement_law#Frequency-dependent_formulationhttp://en.wikipedia.org/wiki/Wien%27s_displacement_law#Frequency-dependent_formulationhttp://en.wikipedia.org/wiki/Thermodynamicshttp://en.wikipedia.org/wiki/Calorimetry


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INFRARED THERMOMETER

An infrared thermometer is athermometer which infers temperature from

a portion of thethermal radiation sometimes calledblackbody radiation emitted

by the object being measured. They are sometimes called laser thermometers if

alaser is used to help aim the thermometer, or non-contact

thermometers or temperature guns, to describe the device's ability to measure

temperature from a distance. By knowing the amount of infrared energy emitted

by the object and itsemissivity, the object's temperature can often be

determined. Infrared thermometers are a subset of devices known as "thermal

radiation thermometers".

Infrared thermometers can be used to serve a wide variety of temperaturemonitoring functions. A few examples provided to this article include:

Detecting clouds for remote telescope operation

Checking mechanical equipment or electrical circuit breaker boxes or outlets

for hot spots

Checking heater or oven temperature, for calibration and control purposes

Detecting hot spots / performing diagnostics in electrical circuit board

manufacturing

Checking for hot spots in firefighting situations Monitoring materials in process of heating and cooling, for research and

development or manufacturing quality control situations

There are many varieties of infrared temperature sensing devices available

today, including configurations designed for flexible and portable handheld use,

as well many designed for mounting in a fixed position to serve a dedicated

purpose for long periods.

The most common infrared thermometers are the:

Spot Infrared Thermometer or InfraredPyrometer, which measures thetemperature at a spot on a surface (actually a relatively small area

determined by the D:S ratio).
http://en.wikipedia.org/wiki/Thermometerhttp://en.wikipedia.org/wiki/Thermal_radiationhttp://en.wikipedia.org/wiki/Blackbody_radiationhttp://en.wikipedia.org/wiki/Laserhttp://en.wikipedia.org/wiki/Emissivityhttp://en.wikipedia.org/wiki/Pyrometerhttp://en.wikipedia.org/wiki/Pyrometerhttp://en.wikipedia.org/wiki/Emissivityhttp://en.wikipedia.org/wiki/Laserhttp://en.wikipedia.org/wiki/Blackbody_radiationhttp://en.wikipedia.org/wiki/Thermal_radiationhttp://en.wikipedia.org/wiki/Thermometer


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Related equipment, although not strictly thermometers, includes:

Infrared Scanning Systems scan a larger area, typically by using what is

essentially a spot thermometer pointed at a rotating mirror. These devices

are widely used in manufacturing involving conveyors or "web" processes,such as large sheets of glass or metal exiting an oven, fabric and paper, or

continuous piles of material along a conveyor belt.

Infrared Thermal Imaging Cameras orInfrared Cameras are essentially

infrared radiation thermometers that measure the temperature at many

points over a relatively large area to generate a two-dimensional image,

called athermogram, with each pixel representing a temperature. This

technology is more processor- and software-intensive than spot or scanning

thermometers, and is used for monitoring large areas. Typical applications

include perimeter monitoring used by military or security personnel,

inspection / process quality monitoring of manufacturing processes, and

equipment or enclosed space hot or cold spot monitoring for safety and

efficiency maintenance purposes.

THERMOCOUPLE

A thermocouple is a temperature-measuring device consisting of two

dissimilar conductors that contact each other at one or more spots. It produces

avoltage when the temperature of one of the spots differs from the reference

temperature at other parts of the circuit. Thermocouples are a widely used typeoftemperature sensor for measurement and control and can also convert a

temperature gradient into electricity. Commercial thermocouples are

inexpensive, interchangeable, are supplied with standard connectors, and can

measure a wide range of temperatures. In contrast to most other methods of

temperature measurement, thermocouples are self-powered and require no

external form of excitation. The main limitation with thermocouples is accuracy;

system errors of less than one degree Celsius (C) can be difficult to achieve.

Thermocouples are suitable for measuring over a large temperature range, up to

2300 C. Applications include temperature measurement forkilns,gasturbine exhaust, diesel engines, other industrial processes andfog machines.

They are less suitable for applications where smaller temperature differences

need to be measured with high accuracy, for example the range 0100 C with

0.1 C accuracy. For such applicationsthermistors,silicon band gap temperature

sensors andresistance thermometers are more suitable.
http://en.wikipedia.org/wiki/Thermographic_camerahttp://en.wikipedia.org/wiki/Thermographyhttp://en.wikipedia.org/wiki/Voltagehttp://en.wikipedia.org/wiki/List_of_temperature_sensorshttp://en.wikipedia.org/wiki/Gradienthttp://en.wikipedia.org/wiki/Celsiushttp://en.wikipedia.org/wiki/Kilnhttp://en.wikipedia.org/wiki/Gas_turbinehttp://en.wikipedia.org/wiki/Gas_turbinehttp://en.wikipedia.org/wiki/Fog_machinehttp://en.wikipedia.org/wiki/Thermistorhttp://en.wikipedia.org/wiki/Silicon_bandgap_temperature_sensorhttp://en.wikipedia.org/wiki/Silicon_bandgap_temperature_sensorhttp://en.wikipedia.org/wiki/Resistance_thermometerhttp://en.wikipedia.org/wiki/Resistance_thermometerhttp://en.wikipedia.org/wiki/Silicon_bandgap_temperature_sensorhttp://en.wikipedia.org/wiki/Silicon_bandgap_temperature_sensorhttp://en.wikipedia.org/wiki/Thermistorhttp://en.wikipedia.org/wiki/Fog_machinehttp://en.wikipedia.org/wiki/Gas_turbinehttp://en.wikipedia.org/wiki/Gas_turbinehttp://en.wikipedia.org/wiki/Kilnhttp://en.wikipedia.org/wiki/Celsiushttp://en.wikipedia.org/wiki/Gradienthttp://en.wikipedia.org/wiki/List_of_temperature_sensorshttp://en.wikipedia.org/wiki/Voltagehttp://en.wikipedia.org/wiki/Thermographyhttp://en.wikipedia.org/wiki/Thermographic_camera


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SAMPLE PROBLEMS

1.) If someone says that the temperature will be 303 K today, how can you

express that temperature in C and F?.

Solution:

To convert from Kelvin to Celsius:TC= TK- 273

TC= 303 - 273 TC= 30C

To convert from Celsius to Fahrenheit:

TF= 9/5(TC) + 32TF= 9/5(30) + 32

TF= 86F

2.) 1.150 g of sucrose goes through combustion in a bomb calorimeter. If the

temperature rose from 23.42C to 27.64C and the heat capacity of the

calorimeter is 4.90 kJ/C, then determine the heat of combustion of

sucrose in kJ.

Solution:

Qcalorimeter= CcalorimeterT = (4.9kJ/oC)(27.6423.42)oC = 4.90x4.22 kJ

Qcalorimeter= 20.7kJ

Qreaction= -Qcalorimter

Qreaction= -20.7kJ

m = 250 grams


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3.) If 150 g of lead at 100C were placed in a calorimeter with 50 g of water

at 28.8C and the resulting temperature of the mixture was 22C, what are

the values of Qlead, Qwaterand Qcalorimeter? (Knowing that the specific heat of

water is 4.184 J/g C and the specific heat of lead is 0.128 J/g C)

Solution:

Q = mCT

Qlead= (0.128J/g-oC) (150g)(28.8-100)oC = -1370 J

Qwater= (4.184J/g-oC)(50g)(28.822)oC = 1420 J

Qcalorimeter= -(Qlead+ Qwater) = -(1420J + -1370J)

Qcalorimeter= -50 J

REFERENCES:

http://en.wikipedia.org/wiki/Temperature_measurement (Date retrieved, May 11, 2014)

http://eo.ucar.edu/skymath/tmp2.html (Date retrieved, May 11, 2014)

http://dictionary.reference.com/browse/temperature (Date retrieved, May 11, 2014)

http://en.wikipedia.org/wiki/Thermometer (Date retrieved, May 11, 2014)

http://en.wikipedia.org/wiki/Infrared_thermometer (Date retrieved, May 11, 2014)

http://en.wikipedia.org/wiki/Thermocouple (Date retrieved, May 11, 2014)
http://en.wikipedia.org/wiki/Temperature_measurementhttp://eo.ucar.edu/skymath/tmp2.htmlhttp://dictionary.reference.com/browse/temperaturehttp://en.wikipedia.org/wiki/Thermometerhttp://en.wikipedia.org/wiki/Infrared_thermometerhttp://en.wikipedia.org/wiki/Thermocouplehttp://en.wikipedia.org/wiki/Thermocouplehttp://en.wikipedia.org/wiki/Infrared_thermometerhttp://en.wikipedia.org/wiki/Thermometerhttp://dictionary.reference.com/browse/temperaturehttp://eo.ucar.edu/skymath/tmp2.htmlhttp://en.wikipedia.org/wiki/Temperature_measurement


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FINAL DATA SHEET

TRIALThermometer

Infrared

ThermometerThermocouple

Boiling Freezing Boiling Freezing Boiling Freezing1 367 276 359 278.2 370.6 273.2

2 366 275 354.6 278.4 370.5 273.7

3 366 274.5 354.6 278.6 370.7 272.9

4 365 275 355.6 279.6 370.6 273.2

5 365 276 354.6 278.8 370.4 273.2

6 366 276 355.6 278.6 370.5 273

7 367 275 354 278.8 370.4 273.4

8 367 275 354.3 278.8 370.6 272.79 366 275 354.1 278.8 370.7 273.1

10 366 275 349 279 370.4 273.2

Ave. 366.1 275.15 353.89 278.66 370.54 273.06

Percent

accuracy1.85% 0.79% 5.13% 2.07% 0.66% 0.022%


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SET-UP OF APPARATUS

A. Set-up of measuring temperature using thermo couple

B. Set-up of measuring Temperature using Bulb Thermometer

Apparatus for

Boiling

Thermocouple

Bulb

Thermometer


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C. Set-up of measuring the temperature using infrared thermometer

Infrared

Thermometer

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Temperature Sensing Instrument