Design requirements memo
- 1. MECH 4010 - DESIGN PROJECT I - MEMORANDUM DATE: OCTOBER 6, 2008 TO: DR. JULIO MILITZER CC: DOMINIC GROULX FROM: GROUP #4 ANDREW MCMURRAY ALEX MORASH BRYAN NEARY KRISTIAN RICHARDS RE: DESIGN REQUIREMENTS FOR STIRLING ENGINE Dear Dr. Militzer, In 2003 a group had previously attempted to design and construct a solar powered Stirling engine for their design project but due to technical problems the project was unsuccessful. After careful analysis of the problems encountered by the previous group and discussing design challenges with our project supervisor we believe that we can successfully deliver a working Stirling engine that can be used for classroom demonstration. The Stirling cycle is an excellent reference for teaching thermodynamic principles and external heat engine cycles. In the recent ‘green-energy’ movement the Stirling cycle has received renewed interest in the area of solar energy generation, and it is the intention of our group to help raise awareness and promote renewable energies by demonstrating the effectiveness of the Stirling engine. Our group has finalized the following objectives and design requirements. Problem Statement: To harness the power of heat and utilize the laws of thermodynamics to efficiently generate mechanical energy. Project Objectives: To design and construct a Stirling engine for demonstration purposes with the ability to function via a solar heat source. Design Criteria & Performance Objectives: The following design requirements summarize the scope of the project and the final goals and objectives we wish to achieve. We are confident that we can deliver a working Stirling engine that will be cost-effective, low maintenance, safe, and of quality in design by applying heat transfer, mechanical and thermodynamic principles. 10/6/08 1
- 2. MECH 4010 – DESIGN PROJECT I – DESIGN REQUIREMENTS FOR STIRLING ENGINE Design & Operational Elements · Must be able to operate using a solar heat source. · Must be able to operate using a compact heat source that is safe for indoor use. · Must be able to operate unassisted after starting for a minimum of 5 minutes (except for a controlling heat source). · Must be built to a standard which delivers a minimum service life expectancy of 5 years, if properly maintained. Size, Weight and Complexity · Total engine size and weight to be such that safe and easy transportation is possible by 1 person. · Must be mounted on a compact support structure for stability and safety. · Will be designed for ease of maintenance and assembly. Aesthetics & Safety · High temperature regions must be clearly indicated. · Engine cylinder must be equipped with a removable fitting for piston inspection and pressure release. Documentation · Supporting documentation and user instructions to be provided for later usage within the Mechanical Engineering department of Dalhousie University. Cost & Materials · Pending the usage of machining time and salvaged components, the prototype is estimated to cost less than $3500. Costs will be finalized in the budget. · Construction materials for the support frame and engine will consist mainly of steel or aluminum, depending on cost, availability, and component purpose. · Precision components such as pistons, piston rings, and bearings may be purchased off the shelf or salvaged. 10/6/08 2
- 3. MECH 4010 – DESIGN PROJECT I – DESIGN REQUIREMENTS FOR STIRLING ENGINE Our group will work together in all aspects of the design process and will take full ownership of the Intellectual Property (IP) of the design. Prototype ownership will belong to the department of Mechanical Engineering of Dalhousie University. Team acceptances: Name: _____________________ Date: _____________________ Name: _____________________ Date: _____________________ Name: _____________________ Date: _____________________ Name: _____________________ Date: _____________________ Supervisor’s acceptance: Name: _____________________ Date: _____________________ 10/6/08 3