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Test Evaluation

Upon reviewing the data that was gathered, it seemed that the load cell was calibrated incorrectly and as can be seen below, has a zero point of roughly (2.6) kg. It also shows that the maximum thrust produced topped off at just over (5) kg (11 lbf). This would mean that the engine only produced 22% of the thrust it was designed for. This outcome is entirely plausible, however, as the injector redesign was poor but necessary. The video of the test fire clearly demonstrates the engine chugging. This phenomenon is due to poor combustion stability which would be the outcome of a single hole injector design. Unfortunately, a pressure transducer could not be integrated in to the design of the engine. Chamber pressure data could confirm intense pressure fluctuations that may have also contributed to the chugging. I theorize that the pressure in the chamber would rise above the injection pressure for a brief moment causing back pressure on the feed line thus closing the fuel check valve. Thi...
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Success!

On Sunday, March 24th, 2019, the AMP-1 Rocket Engine was fired up for the first time and ran a complete (3) second full duration firing. At this time the data from the test is still being evaluated to find how much thrust the engine produced. Pictures and videos of the test are below.

More Flow Testing

These flow tests were mostly to do a check in and out of the control systems to make sure the valves will operate and function at the right time and with a high degree of precision. Flow testing with water does not necessarily give an accurate reading to the amount of propellants that will be consumed during the test as water and kerosene are vastly different in weights and density. 

Electronics Mounting Board

A good mounting area was needed for the power supplies and Arduinos so that they could be securely mounted and not moved. Doing this eliminates additional risk of wires getting caught if the electronics were free floating.

First Flow Tests

As a preliminary test for real flow tests, the plumbing was all hooked up and a simulated 100PSI pressure drop over the injector was tested with water and compressed gas. The results were quite promising but the programming needed some serious work as the valves acted abnormally under certain circumstances. 

Custom Control Board

One of the next big things to do was to create a custom made board to house some electronics on it for control of the ignition, servo motors and load cell. The 16 bit I2C plugs into the female port in the upper right to enhance the signal from the load cell. There is a relay that is hooked up to pin D12 on the Arduino Mega 2560 that will allow 12VDC to flow through the nichrome igniter in the engine and start the ignition sequence. None of the circuits were too difficult to conceive and thus allow for simple plug and play into the two Arduinos to complete test and run the engine. 

Second Propellant Valve Mount and Coupler

Over the course of a few days, the second propellant valve mount and coupler were machined for the oxygen ball valve. This was a very straight forward process as it is identical to the first one made. The last picture in the series is the two valves set up for testing in the bench vise.