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Steam related discussions.
Re: high speed rotary valve - 8 years ago
I know of lots of designs that are running 20,000 to over 30,000 rpm, but I assume you also want to seal high steam pressures. Labrynth seals are the only ones I know of that would work. As far as I can find out, leakage is always a problem with rotary valves at significant pressures. Tom Kimmel's site has several rotary valve engines. Grame Vagg Emory Frank Stover Richard Smith Richarby lohring - SteamStuff
Re: oscillating cylinders? - 8 years ago
The oscillating design pictured avoids some of the leakage problems by using a rotary valve. It still isn't suitable for very high pressures both because of leakage and valve loading from the cylinder forces. Lohring Millerby lohring - SteamStuff
Re: Design of Reciprocating Piston Expanders - 8 years ago
Jim Crank Wrote: ------------------------------------------------------- > Lohring, > Read the article Ken and I did for our SACA > Newsletter, we went into this exact subject. > Jim I did reread the article and see the reference to a controlled bleed into the bottom of the valve actuating piston. It's not clear to me that it woud work as a dependable delay. I'm still thinkingby lohring - SteamStuff
Re: flash steam hydroplanes - 8 years ago
Both are available. Experimental Flash Steam http://www.amazon.com/Experimental-flash-steam-John-Benson/dp/0852423527/ref=sr_1_fkmr0_1?s=books&ie=UTF8&qid=1427035691&sr=1-1-fkmr0&keywords=Benson+and+Rayman+experimental+flash+steam The Westbury book is a lot rarer http://www.amazon.com/Flash-Steam-Application-Model-Practice/dp/090510059X/ref=sr_1_9?s=books&ie=UTF8&qid=by lohring - SteamStuff
Re: Design of Reciprocating Piston Expanders - 8 years ago
Here's a comparison of several mechanical systems. I would like to use the piston as the only mechanical actuator. I think one shot air valves should supply some design inspiration. The basic principle involves a delay through an adjustible bleed to the pilot just like the valve in the Z cycle engine. Perhaps that principle can be applied to something like the Hemick/Crank valve. Lohring Miby lohring - SteamStuff
Re: Design of Reciprocating Piston Expanders - 8 years ago
Bill Gatlin Wrote: ------------------------------------------------------- > Inlet Valve: > > This source of steam could supply the spring > pressure to close the valve and also cool it. The > small leakage around the valves piston goes to the > inlet port. Valve spring eliminated. This could > also work as the return spring for a piston valve > configuration.by lohring - SteamStuff
Re: flash steam hydroplanes - 8 years ago
We're argueing about the same thing. I maintain that there is a sequence in the process of turning cold water into superheated steam. The only issue is how long the sections of tube are for the various steps. Simple flow computations on pump output show that the water flows the length of a model flash steam boiler in around a second. How fast can this water flow turn into steam? Not instantlyby lohring - SteamStuff
Re: Design of Reciprocating Piston Expanders - 8 years ago
Jim Crank Wrote: ------------------------------------------------------- > If you want to learn about springless valve gear, > research the pneumatic valve systems used in > Formula One cars, they can and have gone to 20,000 > rpm which means 10,000 rpm on the camshafts. > What intrigued Ken and I to investigate using dry > steam in place of the nitrogen they use. Thereby lohring - SteamStuff
Re: flash steam hydroplanes - 8 years ago
Sure. That's what White, Doble, and the other steam car builders used. Flash steam is a monotube boiler system. The origonal thiught was that the tubes were dry and the water flashed into steam when it entered the boiler tube. What actually happens is that one section of the tube heats the water, another boils it and a third superheats the steam. Flash steam model hydroplane boilers fail fromby lohring - SteamStuff
Re: Design of Reciprocating Piston Expanders - 8 years ago
I'm also very interested in the valve design. The whole topic of steam pressure operation and steam springs should be a great area for new thought. Springs immersed in steam are an obvious weak point. I keep thinking that the Hemick/Crank "bashless" valve idea could be combined to give a non contact opening with a steam spring return. The system has obviously been tested. I woulby lohring - SteamStuff
Re: Flow through an actuated Valve - 8 years ago
The progression from the early report through the tech notes is an interesting walk through the history of engine development and testing. I'm still debating if air flow at the comparatively low temperatures and pressures would be the same with superheated steam. It should act like an incompressible gas with the (hopefully) low pressure drop through a valve, shouldn;t it? Unfortunately the .pdfby lohring - SteamStuff
Re: Flow through an actuated Valve - 8 years ago
There is a lot of information on poppet valves for internal combustion engines. The intake valve(s) in a four stroke engine are critical. A standard work is "The Internal Combustion Engine---" by C. FayetteTaylor et al. Chapter 12 deals with valves including equations for flow. What's interesting to me is the lack of similar study of flow in reciprocating steam expanders. The pulsatby lohring - SteamStuff
Re: Insulating steam engine cylinders and steam lines - 8 years ago
As a complete novice it would seem to me that wrapping the cylinders in economiser coils would both cool the cylinder and recover the heat. The various results I see indicate piston and liner temperatures don't get above 600 degrees, at least with 1000 degree steam. I still would only consider some kind of steel liner unless you could find a knowledgable ceramic supplier. Lohring Millerby lohring - SteamStuff
Re: california steam bus project - 8 years ago
Do you have pictures/drawings/sketches of the water operated valve system? I'm familiar with hydraulic valves controlled by piezoelectric pilots for four strokes, and something similar might work for steam. Lohring Millerby lohring - SteamStuff
Re: Insulating steam engine cylinders and steam lines - 8 years ago
A very long time ago I was employed in the engineering departments of several companies that were involved with developing new ideas. My favorite example of steam power R&D was the SSN 671. The geared steam turbines of the day were very noisy so the idea was to fit a standard SSN 637 class hull with a direct drive turbine. Needless to say, there were snags. The hull had to be completely reby lohring - SteamStuff
Re: Less resitance - 8 years ago
A lot depends on how high pressure and temperature you plan to run. Your design is way to complicated for a low pressure engine. The simplest engine uses the motion of the cylinder for valving, This design is innefficient and is limited to pressures well under 100 psi. It makes a great small model. High pressure engine design has a lot of issues explored in the article I posted here: http://by lohring - SteamStuff
Re: Insulating steam engine cylinders and steam lines - 8 years ago
After reading all the Cyclone information both here and in the patents on the Cyclone web site I thiught we were at the start of a new steam age. I did notice that there was no mention of a control system, though. I also wanted to see some test data on the water lubrication. Thanks for the update on what happened. Lohring Millerby lohring - SteamStuff
Re: Micro Chuk Williams Combustion Chamber - 8 years ago
Finally, even flow through the nozzles. Lohring Millerby lohring - SteamStuff
Re: Micro Chuk Williams Combustion Chamber - 8 years ago
I've been running the combustion chamber on propane and it all works well. Turning on the blower gets things red hot in a hurry. I need to rebuild the nozzles since some flow better than others. That gives uneven heating. The fuel pump is working as well so the next tests will be with Coleman fuel or kerosene when I solve the nozzle problem. I got an oxygen sensor to calibrate the fuel flow tby lohring - SteamStuff
Re: Micro Chuk Williams Combustion Chamber - 8 years ago
That's what I hope. However, I plan to run quite a lot of superheat. I also have a blower as well as fuel feed to contend with. I noticed that the Carters still used a throttle as well with their variable pressure system. The mechanical simplicity of a variable pressure system is very appealing. The electronics should scale up. Lohring Millerby lohring - SteamStuff
Re: Micro Chuk Williams Combustion Chamber - 8 years ago
This is a brief summary of Ian Gerrard's electronic monotube control system. Any thoughts? Lohring Miller "The main difference with my control system compared with the “traditional” ones that control steam temperature with the pumps and pressure with the heat input, is that I don’t bother controlling the pressure, since both heat input and feed flow affect it. The next control looby lohring - SteamStuff
Re: Micro Chuk Williams Combustion Chamber - 8 years ago
Thanks. That will take some study. At first glance it looks like a propane fired burner. The really high power engines like Pieces II use kerosene from an engine driven pump. Also, I'm not aware of tether boats using a steam seperator. Is there a link to the articles? Lohring Millerby lohring - SteamStuff
Re: throttle losses? - 8 years ago
There have been several threads on throttles. My favorite thoughts are in this thread starting here. It describes a much easier to produce version of the White throttle. Lohring Millerby lohring - SteamStuff
Re: Micro Chuk Williams Combustion Chamber - 8 years ago
Thanks for the thoughts and the video. I plan to try a variable water input as the throttle control as well. My boiler is based on Bob Kirtley's design shown below with input from George Thompson's design. I believe electronic systems should be more adjustable and ultimately simpler than mechanical systems. We'll see if I'm smart enough to make it all work. My favorite mechanical system wouldby lohring - SteamStuff
Re: Micro Chuk Williams Combustion Chamber - 8 years ago
I got the boiler mostly together. A little insulation on the outside and some fittings will make it ready for testing. The water pump is next. The first picture is the coil of 1/4" 316 stainless tubing. The next pictures show the assembled boiler and combustion chamber. Lohring Millerby lohring - SteamStuff
Re: White Paper - 8 years ago
As a new member of this community, I loved the paper. A couple things came to mind. Steam power is alive and well. The electric cars are actually steam powered in most parts of the country. Rather than trying to stuff an efficient steam plant under the hood, electric cars use large steam plants that transmit the power to batteries for short term storage. That way the expensive, mechanical parby lohring - SteamStuff
Re: Micro Chuk Williams Combustion Chamber - 8 years ago
Thanks for the corrections to my over simplified version of the historic control systems. I'm still interested in any experiences with modern electronic controllers. The one referenced above is the only one I can find. I expect that throttle input will go into the Arduino with the blower, fuel pump and water pump as outputs. The big question is how do you use the pressure and temperature inputby lohring - SteamStuff
Re: Micro Chuk Williams Combustion Chamber - 8 years ago
I'm planning on an Arduino as well. However, there are a lot of basic questions. The old monotube controls ran constant pressure and temperature. The temperature was controlled by a normalizer. A throttle controlled engine output. The above mentioned electronic system tried a lot of things but found that constant temperature controlled by the burner with engine output controlled by water feedby lohring - SteamStuff
Re: Micro Chuk Williams Combustion Chamber - 8 years ago
The only electronic control system I'm aware of is for a moderate power system. The seriously fast flash steam hydros all run direct drive fuel and water pumps at a set flow. They run wide open all the time. The only RC flash steam boat I know about has an off/on control. I would be very interested if anyone has more information on electronic monotube boiler controls. Lohring Millerby lohring - SteamStuff
Re: Micro Chuk Williams Combustion Chamber - 8 years ago
This steam power plant will go into an outrigger hydroplane similar to the 26 to 30 cc gasoline engine powered boats. Below is the hydroplane we used to set the gasoline powered hydroplane record in 2004 that still stands. The steam engine will be based on one of these gasoline engine crankcases with a custom cylinder and piston. I also race electric powered boats. The fan speed controller wilby lohring - SteamStuff