Search found 18 matches

by tom-rock
Sun Oct 14, 2018 11:57 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: GPU-3 stirling engine
Replies: 2
Views: 401

Re: GPU-3 stirling engine

Hi,

you can find the Stirling engine design manual free on the internet (as pdf I think).

It has very detailed data of the GPU-3.

Greetings

Ralf
by tom-rock
Sun Feb 18, 2018 1:30 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Temperature/preessure change while running?
Replies: 11
Views: 2171

Re: Temperature/preessure change while running?

Hi steedspeed and all, I have a pressure sensor attached to my stirling engine which measures the working pressure in real time while running. At the moment it has a pressure difference with 10 bar meanpressure of 7 bar (8 bar min / 15 bar max pressure). You can see it in this little video: https://...
by tom-rock
Sun Nov 05, 2017 1:10 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Imploding displacer - make it leaky?
Replies: 3
Views: 1331

Re: Imploding displacer - make it leaky?

Hi Ian, the displacer is made out of titanium which also looses much of its strenght at high temperatures as I read now. Maybe I will try a good titanium alloy or stainless steel if the new one (also out of pure titanium but a bit more sturdy and with 2 instead of 1 radiation shield) which in nearly...
by tom-rock
Wed Nov 01, 2017 1:03 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Imploding displacer - make it leaky?
Replies: 3
Views: 1331

Imploding displacer - make it leaky?

Hi all, yesterday my displacer imploded and it was my second one recently. Now I ask myself if the next one should be more sturdy (which makes it heavier and more heat conducting what I want to avoid!) or if there is a way to make a pressure compensation without creating additional dead space. I thi...
by tom-rock
Tue Feb 23, 2016 1:47 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: New Stirling scaled of GPU 3 first testrun
Replies: 5
Views: 2731

Re: New Stirling scaled of GPU 3 first testrun

Hi, thanks for you kind comments. Ian you are right the big bearings have to much fricton I will fix this in the future, thanks. After fixing countless provisionals my main focus is on finding the right balance between friction and tightness in all seals. (Piston rings and displacer rod seals). I al...
by tom-rock
Sun Feb 21, 2016 1:10 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: New Stirling scaled of GPU 3 first testrun
Replies: 5
Views: 2731

New Stirling scaled of GPU 3 first testrun

Hi, as discussed in an earlier topic I modified my Stirling engine a lot. The heat exchangers are now scaled of the famous GPU 3 with the methods of Dr. Allan J Organ. I hadn´t much time the last month so it took much longer to complete the Engine. A first testrun with a lot of provisionals and by f...
by tom-rock
Mon Apr 13, 2015 10:46 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Rhombic drive calculations
Replies: 4
Views: 3811

Re: Rhombic drive calculations

Hi JR, I used the original publication "The Philips Stirling Thermal Engine" of Roelf Jan Meijer (original invention and intensive analysis of the Rhombic Drive Mechanism) which you can find free in the net. If you search a bit you will find a lot in the net. Also a good explanation is in the Book "...
by tom-rock
Mon Mar 30, 2015 11:05 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Stirling engine with rhombic drive 75 ccm
Replies: 28
Views: 12073

Re: Stirling engine with rhombic drive 75 ccm

Hi all, Plani: I think a lip seal out of W300 will not work because W300 is very brittle and hard. When I take the sealing apart I will male a photo of the face seal. The burner delivers more than enough heat, what I need is additional outside surface on the heater head. It is internally slotted wit...
by tom-rock
Wed Mar 25, 2015 1:04 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Stirling engine with rhombic drive 75 ccm
Replies: 28
Views: 12073

Re: Stirling engine with rhombic drive 75 ccm

Hi Plani, the hot cap glows bright red with 1 bar, with 2 or more bars it doesen´t but it isn´t tested enough because at the moment I can´t heat it up to full red heat because I have problems with intergranular corrosion at the ss-heater head due to the regular red heat, the next one will be out of ...
by tom-rock
Sun Mar 22, 2015 12:57 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Stirling engine with rhombic drive 75 ccm
Replies: 28
Views: 12073

Re: Stirling engine with rhombic drive 75 ccm

Hi, in his book A. Ross writes on several places 230 W at 2,7 bar for this engine and also in third party literature I found this value. And you are right with the Beale number, thats why they are called the benchmark engines. But when I look at the effort they made in research and development in th...
by tom-rock
Sun Mar 22, 2015 11:51 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Stirling engine with rhombic drive 75 ccm
Replies: 28
Views: 12073

Re: Stirling engine with rhombic drive 75 ccm

Hi Aviator, the engine of Andy Ross you mentioned delivers 230 W with 2,7 bar pressure, which ends up in a Beale number of normal range. Comprehensive explanation of the Beale number you will find in older literature e.g. I have the book of Colin West "Principles and Applications of Stirling Engines...
by tom-rock
Sat Mar 21, 2015 12:55 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Stirling engine with rhombic drive 75 ccm
Replies: 28
Views: 12073

Re: Stirling engine with rhombic drive 75 ccm

Hi Aviator, on which calculations is your statement based? When I use the basic Beale equation just to estimate the power output of a carefully designed engine : P = Bn*Pm*f*V0 where Bn = Beale number = 0,15 for a professional designed Stirling (average of commercial engines) , a high Temperature di...
by tom-rock
Fri Mar 20, 2015 12:46 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Heat exchanger design with FastTrack, FlexiScale and ReScale
Replies: 1
Views: 2381

Heat exchanger design with FastTrack, FlexiScale and ReScale

Hi all, for my Stirling engine new heat exchangers are in the planning stage using FastTrack, FlexiScale and ReScale by Dr. A. Organ for a target power of several hundred Watts. If anybody is familar with the scaling methods of Dr. A. Organ I would be very thankful if u contact me here or via e-mail...
by tom-rock
Fri Mar 20, 2015 12:37 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Stirling engine with rhombic drive 75 ccm
Replies: 28
Views: 12073

Re: Stirling engine with rhombic drive 75 ccm

Hi,

power is much increased and an Arduino is added to measure engine data.

I added a new video with many updates at this link:



Ralf
by tom-rock
Sat Mar 08, 2014 3:14 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Stirling engine with rhombic drive 75 ccm
Replies: 28
Views: 12073

Re: Stirling engine with rhombic drive 75 ccm

Hi all, many thanks for your kind comments, there are a lot of interesting ideas and suggestions. I will try pressurising the engine as soon as I improved the other obviously weak points friction, compression and regenerator. The engine is prepared for pressurization up to ten bar, just the seals ar...