NAVAL SCIENCE345 INTRO TO

NAVALENGINEERING

WHAT IS NAVAL ENGINEERING?

“THE TRANSFORMATION OF AVAILABLE ENERGY FORMS INTO FORCES FOR PROPELLING AND OPERATING WARSHIPS AT SEA”

MAKING THE SHIP GO

WHAT’S THE POINT?

YOU are going to be a naval engineer “Technically and tactically proficient” Safety of ship and crew 2/C Cruises & Warfare schools BE THE HERO!

Administrative Matters

Textbooks– Introduction to Naval Engineering– Principles of Naval Engineering

Syllabus– Overview– Grading policy– Responsibilities

Individual Presentation

Independent research Expand on class topics

– Applications– Technological developments

Ability to deliver a 10 min. brief– PowerPoint recommended– Make it interesting– Preview with me

PRINCIPLESOF

MEASUREMENT

INTRODUCTION TONAVAL

ENGINEERING

What does it mean to measure?

IT’S A COMMON LANGUAGE

PROVIDE INDICATION OF PLANT PERFORMANCE

PROVIDE INPUT FOR ALARMS

HOURLY LOGS FOR RECONSTRUCTION(WHAT JUST HAPPENED AND WHY)

What do we measure? LENGTH (in, ft, yd, mi, nm) AREA (in2, ft2) VOLUME (ft3, gal) MASS (lbm) FORCE or WEIGHT (lbf, tons, lt) TIME (s, min, h) VELOCITY (ft/s, mph, kts) ACCELERATION (ft/s2) PRESSURE (psia, psig, in of Hg, in of H2O) TEMPERATURE (oF, R) ENERGY (BTU, ft-lbf) TORQUE (ft-lbf, in-lbf) POWER (ft-lbf/s, ft-lbf/min, BTU/h, hp, MW)

TEMPERATURE

A measure of a substance’s internal kinetic energy

[Simply stated] The degree of hotness or coldness of a substance, as measured on a thermometer

Temperature Conversions Fahrenheit

– oF = (9/5 oC) + 32 Celsius or Centigrade

– oC = 5/9 (oF - 32) Rankine

– R = oF + 459.67 Kelvin

– K = oC + 273.15

Temperature Measuring Devices

Expansion Thermometers– Liquid in glass– Bimetallic– Filled system / distant reading

Pyrometers– Thermocouple– Resistance– Radiation and optical pyrometers

Liquid in GlassThermometer

Bimetallic ExpansionThermometer

DistantReading

Thermometer

Thermocouple

Resistance Temperature Device

Radiation Pyrometer

PRESSURE Force exerted on a unit area Measured in psia, psiv or psig (other

units include atm, in Hg, mm Hg) Atmospheric pressure at sea level is

14.7 psia, 0 psig, 1 atm, 29.92 in Hg, 76.0 mm Hg

PRESSURE

WHICH EXERTS MORE PRESSURE, A 2000 POUND ELEPHANT WHICH HAS A .5 FT RADIUS FOOT, OR A 150 POUND WOMAN ROCKING ON HER HEELS WITH A .5 IN RADIUS?

ELEPHANT- 4.4 POUNDS PER SQUARE INCH

WOMAN- 95.5 POUNDS PER SQUARE INCH

Gage and Vacuum versus Absolute Pressure

Absolute Pressure = Atmospheric Press. + Gage Press.

Vacuum = Atmospheric Press. - Absolute Press.

Don’t have absolute pressure gages

Manometer

Pressure Measuring Devices

Bourdon Tube

Pressure Measuring Devices

Bourdon Tube

Pressure Measuring Devices

Bellows Gage

Pressure Measuring Devices

ACCURACY

KNOWING THE ACCURACY IS JUST AS IMPORTANT AS KNOWING THE APPARENT VALUE

CALIBRATION WITH A STANDARD CRUCIAL PERIODIC

MAINTENANCE…OUR GRIP ON REALITY

Example Problems

Convert the following to oF:– 100 oC– 100 K– 100 R

Convert the following to psia– 100 psig– 10 psiv