Conceptual Design

Functional Decomposition:

At the left is an image of the overall function of the design. An auger feeds wood pellets into the gasifier from the hopper. Ultimately, everything is powered from the gasifier. The gass from the gasifier travels to a generator and a water heater. The generator powers the pumps that must move the glycol through the system. It must also power the control unit and the auger motor. The water heater will burn the gasifier gas for heat.

In addition to the heat produced from burning the gasifier gas in the water heater, heat will be extracted from the generator exhaust and the gasifier gas itself immediately after it leaves the gasifier.

The system must also keep the glycol moving in the event of a gasifier failure, therefore, a propane tank is used as back-up to keep the generator running.

Design Concepts for Functions:

The last four images are the results of our concept generation. The drastic difference in design from beginning to end is well illustrated by the initial and final designs for the hopper. Also, some more designs were decided upon for the glycol tank and the heat exchanger for the generator exhaust. It should be noted that the generator exhaust heat exchanger is made from and existing heat exchanger that is modified to run exhaust through the chamber.

Design Concepts for the Overall Product:

The real challenge for this project is to get many systems to work together effectively. The overall layout of the design leaves little room for "creative" solutions, so most of the effort is centered on the functional aspect of the layout. The functionality affected the layout of the system the most with the hopper. There are certain angles at which wood pellets will slide down the hopper, and we've optimized the angle and shape of the hopper to accomodate the placement of the gasifier.

Concept Selection:

The final concept was basically given to the team. Functionality of the concept is the goal.