Home made rocket engine

[JonClarke]

The results of the tests were:<br /><br />Goal 1: Safe fuel loading and operating procedures.<br /><br />Result: Difficult fuel loading and monitoring of the mass burned.<br /><br />Goal 2: Safe start, run and shut down.<br /><br />Result: Safe. The runs provided confidence in system<br /><br />Goal 3: Software control<br /><br />Result: Could not read input data. Output to field OK<br /><br />Goal 4: Monitoring of the loads and pressures.<br /><br />Result: Required to read gauges using camera.<br /><br />Goal 4: Engine performance.<br /><br />Result: Probably achieved 0.25 kN thrust. Incorrect mixture ratio and poor injector performance.<br /><br />The photo shows the very first run when the ignitor wire burned out before combustion conditriosn were attained. the kerosene can be seen spurting out the nozzle before the test was abandoned.<br /> <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[JonClarke]

The conclusions from the trials are:<br /><br />The rocket engine and testing rig performed well. 3 out of 4 runs were achieved. The longest burn time being 15 seconds excluding the start up and shut down process. <br /><br />A high confidence level in the system and procedures was achieved.<br /><br />However improvements are required. These are:<br /><br />- Replacing the software with standard industrial PLC system;<br /><br />- Improving the fuel loading and monitoring of the fuel and oxygen burn rate;<br /><br />- Providing sand bags around the test rig to absorb explosions;<br /><br />- Improving the injector design;<br /><br />- Monitoring the combustion chamber temperature;<br /><br />- Improving the fuel/O2 ratio; and finally,<br /><br />- Measure the thrust, chamber pressures, chamber temperature and propellant burn rate to provide engine performance data. <br /><br />The plan is to modify the present engine and complete a performance test before building a new engine employing liquid oxygen and kerosene.<br /><br />the photo shows the full up assembled engine and test stand in the workshop.<br /> <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[JonClarke]

Lastly, a photo of his old engine. Unlike the current design it did not have a liquid cooled bell but did use fuel circulation to cool the combustion chamber.<br /><br />Also unlike the present engine it was tested vertically. This worked well until a misfire led to fuel ponding in the engine and then an impresive blow back. At this point my friend abandoned the design and thought up going a new appoach.<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[rocketman5000]

thanks for the update, always cool to see real amateur rocketry in action...

 

[earth_bound_misfit]

"The aim of the engine was as a learning tool intended to develop an understanding of the technical and practical issues in rocket engine design and testing."<br /><br /><img src="/images/icons/smile.gif" /> So making a lot of awesome noise and flame had nothing to do with it <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> <p> </p><p> </p><p>----------------------------------------------------------------- </p><p>Wanna see this site looking like the old SDC uplink?</p><p>Go here to see how: <strong>SDC Eye saver </strong>  </p> </div>

 

[JonClarke]

That's a quote from his conference presentation, so it has got to sound official. <img src="/images/icons/smile.gif" /> The real reason he does it because he finds it relaxing to work with his hands.<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[gunsandrockets]

"Also unlike the present engine it was tested vertically. This worked well until a misfire led to fuel ponding in the engine and then an impresive blow back."<br /><br />Ah, so now I understand the rationale for horizontal testing. Very interesting.

 

[trailrider]

"The aim of the engine was as a learning tool intended to develop an understanding of the technical and practical issues in rocket engine design and testing." <br /><br />That's what mine was "back in the day", although it is also fun! And you never know what such experience can lead to, as was my situation.<br /><br />Your friend may want to consider a better ignition system, however. Probably the best would be some sort of longer-lasting spark plug or blowtorch positioned "up the spout". If you really wanted to get sophisticated (and dangerous to boot), some sort of pyrophoric chemical "slug" in the kerosene line, just ahead of the main fuel, which is spontaneously ignitable with the LO2 would work. That's what they did with the operational Atlas ICBM's. But handling the pyrophoric chemical could be a tad risky!<br /><br />Anyhow, Good on ya, mate! Just be careful!<br /><br />Ad Luna! Ad Ares! Ad Astra!<br />

 

[JonClarke]

As I understand it my friend is quite happy with the ignition system. It only failed the first time because the voltage was too high. <br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>