THE PROBLEM. 4 Million deaths per year from indoor air pollution (2013) Number One cause of death among infants/children

Transcription

1

2 THE PROBLEM 4 Million deaths per year from indoor air pollution (0) Number One cause of death among infants/children

3 CLEAN COOKSTOVE ROBERT BOOMER DAN HOWARTH CARLY PATTERSON ANDREW PUTZ

4 COLLABORATORS LANE KAUFMANN CERAMICIST DR. BRIAN S. THOMPSON FACULTY ADVISOR APPROPRIATE TECHNOLOGY COLLABORATIVE DESIGN CONSULTANTS JOHN BARRIE LORI HART TOM STANTON

5 OVERVIEW Design Challenge Design Specifications Stove Components Combustion Chambers Initial Prototypes Conceptual Design Manufacturing Rapid Prototyping Final Design

6 DESIGN CHALLENGE Develop an affordable, clean, wood-burning stove for the impoverished families of Guatemala.

7 GUATEMALA Population using wood for cooking:.% Income per day (USD): $7.84 Population using improved biomass cookstoves: 0.75%

8 DESIGN SPECS DESIGN SPECIFICATION WEIGHT SIZE WEIGHT 7 SPATIAL CONSTRAINTS ENERGY CONSUMPTION 9 TRANSPORTATION AND PACKAGING 7 ENVIRONMENTAL ISSUES AESTHETICS PRODUCT COST 7 OPERATING COST SAFETY OPERATING INSTRUCTIONS HUMAN FACTORS HEALTH ISSUES QUALITY 0 5

9 COMPONENTS Fuel Sources Heating Interface Exhaust Systems Combustion Chambers Auxiliaries

10 FUEL SOURCES Biogas Biomass Crops Landfill Gas Alcohol Fuels Charcoal Pellet Briquettes Solar

11 HEATING INTERFACE Plancha/Griddle Pot skirts Grate Radiant Heat Forced Air

12 EXHAUST SYSTEMS Straight Flue Balanced Flue Valve System

13 AUXILIARIES Lid vs. No Lid Drying the Wood

14 AUXILIARIES Emissions Testing Thermal Electricity

15 AUXILIARIES Heating the Home Diverting Exhaust Heating Bench Heat Exchanger

16 COMBUSTION CHAMBER Rocket Chamber Top Lit Up-Draft J Chamber

17 COMBUSTION MATRIX Rocket Stove TLUD Open Air Down Draft Charcoal Ideal Rocket Stove TLUD Open Air Down Draft Charcoal Ideal Design Spec Design Weight SIZE WEIGHT SPATIAL CONSTRAINTS ENERGY CONSUMPTION TRANSPORTATION AND PACKAGING Scores Weighted Scores ENVIRONMENTAL ISSUES AESTHETICS 8 8 PRODUCT COST OPERATING COST SAFETY OPERATING INSTRUCTIONS HUMAN FACTORS 9 HEALTH ISSUES QUALITY Totals

18 INITIAL PROTOTYPES

19 BOILING TEST Boiling (w/ Lid) Boiling Test Stove Temperature (*F) 50 Time minutes Rocket 00 TLUD 50 Delta Time % Difference 9 4% Rocket 00 TLUD Time (minutes) 0 5

20 FUEL CONSUMPTION Rocket vs. TLUD 5 Temperature (degree f) Rocket 90 TLUD Time (minutes) 4 8

21 TLUD BREAKDOWN Combustion Chamber Gasket Burning Syngas Secondary Air Inlets External Housing Volatile gasses (syngas) rise and mix with hot Wood secondary gasifies dueairto heat and primary combustion Primary Air Inlets Colder Intake Air

22 TLUD BREAKDOWN ~500 to 00 F for Wood Pyrolysis Creates Charcoal ~00 F and higher for Gasification requires controlled oxygen intake

23 TLUD BREAKDOWN Reburn the Syngas : Hot air and Syngas Secondary burn effect Reduces toxic emissions

24 COMBUSTION WITHIN A TLUD Wood comprised of Cellulose Hemi-Cellulose Lignin Oxygen required for chemical reactions Energy or Heat!

25 Energy Generated Q = χ*m *Af*ΣHc (Joules) Heat Release of reactants Methane.0 MJ/lb BTU/g Hydrogen 09. MJ/lb BTU/g

26 Radiation q = εσ A (Ts4 - T 4) σ = 5.7E-8 W/m Boltzman Constant Ts = Surface Temperature T = Surrounding Surface A = surface Area ε = Emissivity of the material Pine Wood -.90 Clay/Pottery -.95 Steel -. -.

27 Conduction q = -k A dt /dx A = area of the Plancha dt/dx = Temperature change over thickness K= Thermal Conductivity {W/(m.K)} Pine Wood - 0. Clay/Pottery.0 Steel 45.0

28 Convection q = hc A (Ts-TA) Ts = Surface Temperature TA = Temperature of the air A = Surface Area hc = Heat transfer coefficient

29 CONCEPTUAL DESIGN

30 PERFORMANCE TEST

31 RAPID PROTOTYPING Combustion Chamber Lower Hole Upper Hole Time / shim Size Distance Size Distance :49 7: : :5 5: :00 5: : : 7:9

32 OPTIMIZATION TEST

33 FINAL DESIGN Manual For Education Plancha Combustion Chamber Flat Stones Combustion Housing Adobe

34 Preguntas? (QUESTIONS)