Dana Levine Maritza Ruiz León Liu Daniel Talancón Esteban Mendoza

1. Dana Levine Maritza Ruiz León Liu Daniel Talancón Esteban Mendoza Stove Improvement

2. Summary of Research • Video of stove in use • Most stoves are not enclosed • Biggest complaint about current stoves • Smoke • Those interviewed are aware of the health risks associated with smoke • They would be willing to modify their stoves • $37 US per month in wood

3. Design Motivation • Reduce smoke emission • More fully enclose the combustion chamber • Utilize existing ventilation • chimney • Reduce smoke production • More efficient combustion • Better air flow • www.youtube.com/watch?v=A7EWQMnNGt0

4. Refined Engineering Specs • Door assembly • Dimensions: • 5”x22”x2” solid • Material: Adobe Clay • Reinforced with straw • Rigidly mounted on 2 bricks • 6.5x11x23 (cm) Figure showing Primary air intake And door assembly

5. Refined Engineering Specs • Pipe Assembly • Dimensions of each U-bent pipe • 1” dia. x 66” long • top-half perforated with 1/8” holes • 2 U-pipes are bound together with wire • Allow for different stove sizes Figure with semi- perforated U-bent pipes

6. Physical Interactions • User Interactions • Pipes removable for cleaning • Hose or Brush • Door is easy to move • Bricks do not get hot (material) • Can rest on back for loading • Can be tilted forward to check fire • Can be removed entirely for pipe removal/stove cleaning • Stove Interactions • Geometric Considerations

7. Functional Interactions • Door (Integral) • Blocks bears the load of the door (cemented on) • Blocks elevate door • Door blocks smoke from entering room • Elevated door allows for primary air to reach flames • Interaction between door and pipes • Provides increased smoke concentration • Retains heat to increase chamber temperature • Elevated bricks allow for pipes to be exposed to air

8. Functional Interactions (cont’d) • Secondary Air Intake (Integral) • Oxygen deficiency in combustion chamber creates a current of air being sucked into the stove • Heat from fire warms air • Perforated tubes release warmed oxygen into combustion chamber • Increased smoke concentration and higher chamber temperature ignites smoke near perforated tubes • This improves the efficiency of burning • Results in less wasted fuel

9. Prototype Development and Testing • Development • Examine choice of door • Material, dimensions, and handle placement • Assess efficacy of secondary combustion system • Vary the number and arrangement of U-tubes • Testing • Use a surrogate stove to measure: • Qualitative decrease in smoke production • Quantitative increase in efficiency • Based on results, we will select our final design

10. Key Business Goals:Manufacturing • Independent production of door assembly and metal tube assembly • Determine cost of raw materials • Bulk discount? • Establish partnership with laborers/artisans for production • Fix wages for laborers • Secure a place for storage of finished products • Factor cost of transporting raw and finished goods

11. Key Business Goals: Marketing • Select representative for selling our product • local hardware store • independent vendor • Offer of demonstrations • Decide whether vendor will help with installation • Assess effect on price vs. likelihood of consumer purchasing • Choose sales strategy • Sell product as a package (with replacements) • Establish prices • Distinguish vendor’s price with final consumer price

12. Key Business Goals: Sustainability • Expand business model to accommodate other local villages • E.g. Hardware store services several communities • Encourage households to keep track of wood consumption • Identify how much money/wood is saved with use of product • Promote maintenance of product • Tips or accessories for cleaning • Replacement parts

13. Proposed Business Plan • Partner with central hardware stores • Provide services to multiple villages • Supply stove improvement kits • With replacement parts • Hardware stores install and maintain stove modifications

14. Challenges • Technical • Design Constraints for Prototypes • Door: requires heat resistant, durable and light weight material. • Secondary Combustion System: requires flexible and environmentally stable tubing. • Maximize safety, comfort and ease of use and maintenance. • Performance Uncertainties to be Tested • Door: might not effectively insulate heat and smoke without a tight seal. • Secondary Combustion System: might not produce the desired effects due to design constraints. • Minimize negative overlap between subsystems.

15. Challenges (cont’d) • Difficult to acquire reliable and accurate data. • Need to build a similar stove model to perform testing. • Hard to quantify desirable properties such as efficiency, smoke reduction and ease of use. • Minimize downtime and the risk of physical injury in case of malfunctions. • Avoid causing unacceptable changes to users’ habits.

16. Challenges (cont’d) • Financial • Performance vs. cost tradeoff • Door material • Quality and quantity of secondary air tubing. • Simplicity vs. effectiveness of specs. • Economy of scale • Minimizing overhead and maximizing value to producers. • Possible need for sponsorship and subsidy.

17. Challenges (cont’d) • Logistical • Establish partners for promotion, production, delivery and maintenance for the product and its separate components. • e.g. hardware stores, cement mixers, pipe-benders, advertising and delivery personnel. • Facilitate and effectively coordinate operations and communication among stakeholders. • Increasing complexity with increasing scale.

18. Address the Challenges • Perform more research • Contact hardware store with questions • Contact cement mason in Pasajquim • Contact adobe mason near TPS • Test and Analyze Data • Build a stove • Iterate Development • Build a prototype • Learn to use adobe • Learn and Repeat

19. Teamwork • Used the teamwork rating form from Jeff Kranski • Everyone was satisfied with the load distribution • Equal work • Clear jobs • Punctuality can be improved (all guilty) • Busy schedules