EML 4304L Thermal Fluids Lab Thermal ConductionExperiment # 3Mechanical Engineering Department FAMU/FSU College of Engineering

Mechanical Engineering Department FAMU/FSU College of EngineeringOutlinePurpose of the labTesting Equipment The types of equipment setupUnits 3 and 4Units 1 and 2 Additional componentsHeat sinksDrain tubes Calculations Needed for Experiment

PURPOSEConduct a series of thermal conduction experiments which examines the effects on heat transfer with varying cross-sectional area and distance. Using this thermal conduction information derive Fouriers law of thermal conduction.Analyze the temperature variance in a series of metal rods that are in physical contact. From this information determine thermal resistance and contact resistance.Mechanical Engineering Department FAMU/FSU College of Engineering

Testing EquipmentFor ExperimentsMechanical Engineering Department FAMU/FSU College of Engineering

Mechanical Engineering Department FAMU/FSU College of Engineering

Mechanical Engineering Department FAMU/FSU College of Engineering

Mechanical Engineering Department FAMU/FSU College of EngineeringTemperature adjustor forUnits 3-4

Mechanical Engineering Department FAMU/FSU College of Engineering

Equipment for Thermal Conduction Test Units #3 and #4

Mechanical Engineering Department FAMU/FSU College of Engineering

Mechanical Engineering Department FAMU/FSU College of EngineeringHeat flowfor units 3 and 4

Mechanical Engineering Department FAMU/FSU College of EngineeringHeat flowfor units 3 and 4Notes: Do NOT adjust the flow valves.

UNIT #3x2x1T1T2Q=KA*T/xK = coeff. of therm. conductivityNOTE: K is unknown and must be determinedMechanical Engineering Department FAMU/FSU College of Engineering

UNIT #4x2x1T1T10Q=KA*T/xK = coeff. of therm. conductivityNOTE: K is unknown and must be determinedMechanical Engineering Department FAMU/FSU College of Engineering

Equipment Thermal Resistance and Contact Resistance Test Units #1 and #2Mechanical Engineering Department FAMU/FSU College of Engineering

Mechanical Engineering Department FAMU/FSU College of EngineeringHeat flowfor units 1 and 2

Mechanical Engineering Department FAMU/FSU College of Engineeringelements are enclosed in the insulating jacket. Figure1 illustrates the schematics of the apparatus. The dimensions of the tapered rod are indicated in Fig. 2.

elements are enclosed in the insulating jacket. Figure1 illustrates the schematics of the apparatus. The dimensions of the tapered rod are indicated in Fig. 2.

elements are enclosed in the insulating jacket. Figure1 illustrates the schematics of the apparatus. The dimensions of the tapered rod are indicated in Fig. 2.

Heat flowfor units 1 and 2

Units #1 and #2 Cu (Al)Contact ResistanceT1T10x1x2Stainless SteelSteel (Mg)Mechanical Engineering Department FAMU/FSU College of Engineering

Heat SinksOne water cooled heat sink is located on each unitUnits #1 and #2 they are located at extreme end of the assembly away from the heat sourceUnits #3 and #4 are located on the top of each unitThe heat sinks will be used to determine heat lost by each unit.Q=mwCp(T)

Mechanical Engineering Department FAMU/FSU College of Engineering

Drain Tube Flow Rate CalculationsMechanical Engineering Department FAMU/FSU College of Engineering

Mechanical Engineering Department FAMU/FSU College of Engineering

Mechanical Engineering Department FAMU/FSU College of EngineeringAlso will needa stopwatchto time fluidflow

CalculationsMechanical Engineering Department FAMU/FSU College of Engineering

Mechanical Engineering Department FAMU/FSU College of EngineeringConservation of Energy(in a perfect world)

qin = q out CalculationsConservation of Energy(in our world)

qin = Cq out

Where C is a constant which represents any losses not accounted for.

Units #1 and #2Stainless Steel Cu (Al)Steel (Mg)Heat InHeat SinkQ=mwCp(T)Qout=QinRt,c= T/QMechanical Engineering Department FAMU/FSU College of Engineering

Mechanical Engineering Department FAMU/FSU College of EngineeringCalculationsThermal Contact ResistanceRt,c = Thermal contact resistanceT = Temperature change q = Heat flux

UNIT #3x2x1QoutQinQ=mwCp(T)Qout=QinQ=KA T/xMechanical Engineering Department FAMU/FSU College of Engineering

Mechanical Engineering Department FAMU/FSU College of Engineering(1) Rate of heat flow at the sinkmw = mass of cooling water displaced in time tCp = Specific heat of water at constant pressureT = (Tout - Tin) of cooling watert = time required to displace a volume Vw of water

(2) Relationship between heat flow and temperature differenceK = proportionality constantA = cross-sectional areaT = temperature difference of the materialx = distance(1)(2)Calculations

CalculationsQ=KA T/x Q=-KA dT/dxdT/dx = temperature gradient

xTdT/dxMechanical Engineering Department FAMU/FSU College of Engineering

ErrorsTimeFlow rateSteady StateHeat LossesNot perfectly insulated

Mechanical Engineering Department FAMU/FSU College of Engineering