beta engine design

[dwchio]

Is there any place that you can get actual dimensions of parts for a beta style engine. For example, how thick of a displacer do you need for a given volume of the cylinder, stroke versus bore? Is there a specific range of weight for the displacer? is the engine more efficent the greater the tempeture difference between the plates?can the difference ever be to great? practicle numbers and formulas is what I am seeking. If air is used as the gas in the cylinder how do you keep the moisture from condensing on the walls? If anyone could point me in the right direction, I will do the heavy lifting and research on my own. Any help would be greatly appreciated

[Ferraccio]

Welcome!
Well only few questions... right?
There are many answers, and all us will be able to give you.
- I propose a book for you: "Making a Stirling Engine", by Andy Ross.
- I propose also a bit of study about how the engine runs.
When you know how the engine runs you have itself many answers.
- Are written other books about (I suppose a your serious approach to the matter).
I only do a question: why to do a Beta, that is the more difficult to built, and is not said is the more performant, for (I suppose) a beginner?

Simple answers:
- Displacer: thinner (and Lighter) as possible and bad heat conductor as possible.
- Cylinder: in good performance MAY be stroke is smaller than diameter.
- Greater difference of temperature? Yes,If you think the plates are ones of colder, and hottest site.
- Particle numbers... read abovesaid Andy' book.
- If air ....: ! In the engine nothing goes in mixture, and nothing condense ON the walls, is NOT a steam engine!!
- I will do the heavy lifting and research.. : yes you must have.
I'm allowable to speak you about how the engine runs,
Ferraccio

[Ferraccio]

Speaking you about beta type I suppose your interest in medium-level well-performant engine.
A simple research in you tube (digit: "stirling engine") demonstrate that the question is more complex than you think.
And answers may are many, and contrasting, so how are different the types of engines: dimensions "designs", materials, temperatures, pressures.
You need to understand on wich level is your goal, and adress you in this direction.
Ferraccio

[dwchio]

Thanks Ferraccio, I will grab that book. The reason I asked about condensation was at some point heating a gas and compressing it I would expect some some condensation from plain air but that is purely speculation on my part ----hence me asking. I appreciate all the advice and info given and look forward to hearing from you again. I chose the beta type because to me it makes more sense visually and I am looking for something more compact such as a single cylinder. Once again thanks for the input and would love to hear from anyone else out there

[Ian S C]

dwchio, The best books that I have are by James G. Rizzo, the first, a paper back "Modelling Stirling and Hot Air Engines", the second is vol 1 "The Stirling Engine Manual". There is a second volume of the "Stirling Engine Manual" which is a bit more advanced than the first, unfortunately I have not been able to get that one yet. Either of those first two books will tell you all you need to design a good working motor. Ian S C

[dwchio]

Thanks Ian, I will look for them. I did get the Andy Ross download and it was very informative I look forward to finding your recommendations and reading them. Once again, thanks for you input : )

[theropod2]

Thanks Ferraccio, I will grab that book. The reason I asked about condensation was at some point heating a gas and compressing it I would expect some some condensation from plain air but that is purely speculation on my part ----hence me asking. I appreciate all the advice and info given and look forward to hearing from you again. I chose the beta type because to me it makes more sense visually and I am looking for something more compact such as a single cylinder. Once again thanks for the input and would love to hear from anyone else out there

RE: bold above;

I notice condensation in the glass/graphite power cylinder on my "Ugly Duckling" walking beam (see my photo log here). I live where the humidity is often quite high. I think this is forming in metal engines too, but can't be seen. I do notice this goes away as the engine runs for a while. I think maybe the glass has to warm up some is why it becomes less noticeable as the engine runs.

R

[gemmalynnlimos]

I am looking for some best books which provide some technical tips for designing an automobile engine and transmission.

[Ian S C]

gemmalynnlimos,I think you might have to join General Motors and their experimental department, then steal their information. Or more practically design your own. How many million do you have in the bank? Ian SC

[Ferraccio]

First, the positive thing:
Is good if you look for a book: this means that you like to be informed.

Few considerations:
If you want a book for built/design a Stirling engine for a car this means that you do not know how the engine functions. This book do not exist.
The Strirling is not at all adapt to drive a car. Unless this is made in a ​complex (heavy, expensive) hybrid powertrain, and equal electrical storage.
All design till now done (by big companies) was really high level project, expensive, that (all) failed.
Symply the S.Engine do NOT allow to be used in variable speed of rotation; for this is not adapt to drive the weels, in any way.
Is better if you read a basic book on how the engine runs.
Many in the forum 'll be able to give you informations.
If you have many money to spend, please send us ;-).
Ciao Ferraccio

[Ian S C]

Phillips and DAF in Holland did some work on vehicles, a bus and car, they used a constant velocity drive, the engine ran at a fixed speed, the vehicle speed was adjusted by varying the ratio of the transmission. The transmission was by belts and expanding pullies. Ian S C

[Ferraccio]

Is really difficult that is simply a question of variable transmission.
The engine do not bears variation on load; variation of load influences the engine rotation speed.
If rotation speed goes over standard, the max yeld drops to minimum, and engine stops.
May be is necessary a energy buffer also (electr.batteries), and electronic devices to maintain costant the load.
Resuming, starting from the engine:
- Electrical generator
- Energy buffer
- Electronic devices to drive electr. energy
- Electr. motors and transmission to drive the weels

All this is heavy and expensive; few prototypes are built, (covered by many patents), but this is all.

[Ian S C]

Ferracio, I agree, the ideal way of using a stirling engine in a car is to have a battery powered car, and use thw stirling engine to charge the batteries. My idea for an electric car is to have two sets of batteries,one in the car, and the other at home being charged by solar cells/ wind turbine, or some such low cost charging system. Next day you change batteries. Ian S C

[Ferraccio]

Speaking about a car (example a small city slow speed autobus or city car), a small (e.g. 3 kw pressurized engine) Stirling, may continuously supply power to a buffer system, increasing the batteries autonomy (the main part of time of a city car is stopped).
The continuous combustion give the lower pullution possible in combustions.
There are however logic conditions:
Power supply have to be accepted as very low = small weight, low speed.
Combustible have to be as possible low polluting: example vegetable oil, or other "on site" material.
Circulation normatives favorite very low pollution drive.