TEAM: JEFF PHILIPPART, TEAM MEMBER NAMES REMOVED WHIRLPOOL CAPSTONE STEAM GENERATION PROJECT

INITIAL DESIGN CONCEPTS Ultrasonic Humidifier Uses piezoelectric transducer to vibrate water droplets into vapor. Produces “Cool Mist” immediately with no warm up time. Boiler Steam exits boiler after it reaches vaporization point. Impeller Humidifier Fan pulls water droplets through diffuser and into atmosphere. “Invisible Mist” exits fan after water moves through diffuser

TESTING METHOD Gauze attached to thermocouple as wet bulb The end of the gauze was placed in a measuring cup of water Second thermocouple used as dry bulb The convection fan was run continuously

PERFORMANCE AT 350° F The boiler performed the best at 350 degrees Fahrenheit

PERFORMANCE AT 450° F The humidifier performed the best at 450 degrees Fahrenheit

FMEA ProductFuntionPotentional Failure ModeSeverityPotention Root CauseOccurance RatingCorrective Actions Ultrasonic Humidifier Provide Steam To Oven Cavity Tranducer Fail 10Hard Water5Customer Instructions: Deionized Water 10System Flood4Use Corrosion Resistant Material Tubing Leak10Material Wear5Use Stronger Heat Resistant Tubing Cloged Transducer10Hard Water5Customer Instructions: Deionized Water Steam Boiler Provide Steam To Oven Cavity Boiler Reserve Leak 10Material Corrosion5Use Corrosion Resistant Material 10Resevoir Scaling5Heating Element in Water Resevoir Tubing Leak10Material Wear5Use Stronger Heat Resistant Tubing Overflow10Customer Error6Add Failure Valve Drain ValveDrainCustomer Getting Burnt10Hot Water Draining5Auto Valve Drains When Cooled

BOILER CONSTRUCTION CONSIDERATIONS Recycles no parts from the steam generator used in performance testing. Water reservoir will maximize the surface area that will be exposed to the external heating plate constructed from welded aluminum. Heating plate will be constructed from scrap range top element received after the oven breakdown Electric coils will be removed and set in a non-conductive base plate Coil path will be milled into the base plate. Glass plate will be cut to size and attached to the base plate with an adhesive. Steel brackets will be bent to mount the prototype behind the oven cavity. Rubber top will be purchased and hole for nozzle drilled Boiler construction considered “reasonable” and scores middle value of 2 on Pugh matrix.

HUMIDIFIER CONSTRUCTION CONSIDERATIONS Many recycled parts from the ultrasonic humidifier used during the performance testing Wires on the humidity level switch and led light will be stripped and extended Switch and LED light will be mounted below stove knobs Re-designed body will be 3-D printed and contain humidifier components. Mounting brackets will be made from bent steel to secure body behind oven cavity Humidifier construction is considered “good” and scores best score of 1 on Pugh matrix

COST Boiler Humidifier Boiler Design Cost partsize/type/quantiyCost nichrome wire5 ft$5 aluminum body1$7 switch1$2 rubber top1$3 heat resistant tubing1$1 water resevoir1$2 drain valve1$1 water sensor1$1 led light1$2 lock1$1 TOTAL $25 Humidifier Design Cost partsize/type/quantiyCost transformer1$6 transducer1$4 small fan1$2 wiring3 ft$1 circuit board1$4 water sensor1$1 led light1$2 switch1$2 water resevoir1$2 body1$5 drain valve1$1 TOTAL $30

RELIABILITY Ultrasonic HumidifierSteam Generator Comparison Quality of Steam Impure water mist could be directly injected into the oven cavity if water in the reservoir is contaminated. Customer Introduction is needed. As the water goes through the boiling process, there is less possibility of impure steam being injected to the oven cavity. Steam generator has less possibility of having contamination issues. Warm-up Time Water mist is formed as soon as the system is turned on. Users can find out whether the humidity feature is properly working or not immediately. It takes about 12 minutes for boiling water. But the oven also needs time for pre-heating. Ultrasonic humidifier works much faster than steam generator. Ultrasonic humidifier requires no warm up time. Quality of Food Cold mist injected into the oven cavity could cause a temperature fluctuation which affects the quality of food. As the heated steam is injected into the oven cavity, there are less food quality issues due to temperature. Ultrasonic humidifier is expected to have a higher possibility of food quality issue. But further testing is required to verify it. Control The flow rate can be easily controlled by adjusting the vibration speed of the unit. Users can easily adjust the flow rate with a knob. The flow rate can be easily controlled by adjusting the electric current with a knob. Flow rates of both systems can be easily controlled by users. Maintenance As fewer components are required for installing a mist generating unit into the oven, there are less maintenance issues. Components such as a transducer and a fan are easily replaceable. There are also scaling issues. Additional Heating components are required for boiling water. Same as an ultrasonic humidifier, there are scaling issues. (run vinegar through it to clean it) Ultrasonic humidifier requires less effort for maintenance. But both systems has common scaling issues which affects the life time of each system greatly.

PUGH MATRIX Pugh Matrix DesignFMEACostPerformanceApplicationConstructionReliabilityUsabilityTOTAL Humidifier Boiler good 2-reasonable 3-poor

Water Entrance Vapor Exit 3-D DESIGN

Water Drain Fan Entrance Circuit Board

Transducer Water Sensor

Flow onto Transducer Plunger Path for fan flow

Water Entrance Switch Low Water LED

Vapor CAVITY Entrance Body Transformer Regulator

DESIGN MODIFICATIONS Vapor Exit Ramp Angled Vapor Exit Extended Roof

DESIGN MODIFICATIONS Floating Magnet Altered Dimensions

COMPLETE PROTOTYPE Oven front (above) Prototype and connection mounted on the oven back (right) LEDSwitch Prototype Water Inlet Prototype Water Reservoir

TESTING RESULTS AT 350°F

TESTING RESULTS AT 400°F

TESTING RESULTS AT 450°F

BREAD TESTING METHOD Oven pre-heated to 350 °F Thermocouple placed approximately 2 inches into dough Desired Thermocouple reading of 93° C (200 °F)

BREAD TESTING RESULTS With Prototype Normal Oven Conditions

MODIFICATIONS AND SUGGESTIONS FOR FUTURE IMPROVEMENTS Design permanent water reservoir and water inlet CNC Machine components from heat resistant plastic Design smaller fan and scale down body size to accommodate limited space at oven back A larger piezoelectric plate could increase the water vapor production Add required circuitry to central board to eliminate humidifier board, transformer, and regulator Move LED and switch for better physical appearance ProductFuntion Potentional Failure ModeSeverityPotention Root CauseOccurance RatingCorrective Actions Humidifier Prototype Provide Steam To Oven Cavity Tranducer Fail 10Hard Water5Customer Instructions: Deionized Water 10System Flood4Use Corrosion Resistant Material Tubing Leak10Material Wear5Use Stronger Heat Resistant Tubing Cloged Transducer 10Hard Water5Customer Instructions: Deionized Water 10Material Corrosion5Use Corrosion Resistant Material