This document summarizes a student project to design and build a small-scale gamma type Stirling engine. It has 30 hand-machined parts made of materials like aluminum, steel, and bronze. The student's goals were to gain engineering design and manufacturing experience, and to better understand thermodynamic principles. Although final testing was not completed due to a fire, the student achieved all goals and gained valuable experience that will benefit their engineering career.

1. Gamma Type Stirling Engine
Austin Holmsley
Computer rendering (flywheel not shown) Computer rendering (flywheel not shown)
Computer rendering (cylinders hidden)
Specifications:
 30 hand machined parts
 Materials Used – Al 6061, mild steel, oil
impregnated bronze
 Bore = .75 in
 Stroke = 1 in
 Theoretical RPM = 1000+
Goals:
 Practice the engineering design process
 Develop CAD modeling and analysis skills
 Gain experience with machine tools such as the mill/lathe
 Gain a deeper understanding of the underlying thermodynamic principles
 Apply force analysis for dynamic balance
 Have fun
Description:
The Stirling Engine is an external combustion engine commonly used before the advent of internal
combustion. Their high efficiency and ability to run off a general heat source make them a desirable
option for power generation in modern day space exploration. The engine built in this project is a small
scale model of early Stirling Engines. I designed and manufactured each component of the engine.
Results:
After 150+ hours of design and machining I achieved all of the project goals. Final testing was never
completed due to a house fire in which the engine was destroyed. Despite this, the valuable experience I
gained during this project will benefit me throughout my engineering career.