Power piston sizing for Stirling engines

Power piston and displacer sizing chart for Stirling engines

One of the more difficult yet critical issues in designing your first Stirling engine is deciding on the correct power piston displacement. My earlier discussion of power piston sizing did not satisfy a lot of people. So I’m going to make this one very simple to apply. For me to suggest the right size power […]

1 Watt Stirling engine driving high-power LED

makerfaire

First let me say I will display this engine and generator at the Maker Faire in San Mateo, CA on May 21, 22 so you can see it running if you are there. The above video shows a one-watt Stirling engine driving a one-watt LED. Conversion efficiency is not too high so I’m only driving […]

Engine 3F Efficiency Analysis part 4

Rev 1: See details at bottom. Let me summarize what has been covered and what remains in this efficiency analysis: Component Power percentage of total power Efficiency analysis Heat lost directly to the environment 40.3w 58.4% Part 1 Thermal shorting: heat conduction directly from the hot end to the cold end 5.9w 8.6% Part 2 […]

Engine 3F Efficiency Analysis part 3

Let me summarize what has been covered and what remains in this efficiency analysis: Component Power percentage of total power Efficiency analysis Heat lost directly to the environment 40.3w 58.4% Part 1 Thermal shorting: heat conduction directly from the hot end to the cold end 5.9w 8.6% Part 2 Gross engine power: includes net shaft […]

Engine 3F Efficiency Analysis part 2

Continuing with the analysis of where the input power (heat) to the engine goes, the next item to consider is the conduction loss often referred to as thermal shorting. Conduction losses A Stirling engine of gamma configuration, such as the one being considered, uses a displacer to shuttle the operating gas back and forth between […]

Engine 3F Efficiency Analysis part 1

IMG_2641E1

In an earlier post I measured 1.05 watts output from my engine 3F using a 69 watt input. This computes to 1.5% efficiency. So where did the other 68 watts go? The following is my analysis of where all the energy went. It won’t be as rigorous as I would like, partly due to lack […]

Measuring a Stirling engine with 1 watt power output and 1.5% efficiency

MVI_0389_0007

The following is a transcript with still photos of the previous video on the same subject. I’ve included a few more notes about the engine, my model 3F. This is a gamma configuration Stirling engine. I’m powering it with the heat from a 70 watt light bulb so that I can accurately measure the heat […]

Measure the power and efficiency of your Stirling engine; it’s easy

In the world of small Stirling engines everyone seems to talk about power and efficiency—but you seldom see the facts and the data. Just a couple days ago I saw the following Stirling engine on Youtube: The promoter claims it must be putting out 100 to 150 watts. It was the usual unloaded engine spinning […]