Purdue Undergraduate Rocket Propulsion Lab

Leading a multidisciplinary student team to develop a modular plug-and-play rocket engine for a cutting-edge regenerative cooling challenge

Maelstrom Engine

The Maelstrom engine is a 500-lbf pressure-fed RP-1/LOx rocket engine. Designed for the Reaction Research Society regenerative cooling challenge, the thruster utilizes a bi-liquid coaxial swirl injector design for maximum propellant and oxidizer atomization.

Maelstrom Thrust Chamber Assembly

COAXIAL SWIRL INJECTOR

The Testbed team has a special place among other PURPL projects. Its purpose is to explore, develop, and test some of the more advanced technologies that are commonly used in the industry.

One such technology that made its way on the first iteration of the Testbed Engine, Maelstrom, is a bi-liquid coaxial swirl injector.

Due to the complex geometry, the injector manifold was designed for additive manufacturing before being printed by Protolabs and post-machined in-house.

AUGMENTED SPARK IGNITER

Being a bi-liquid engine, Maelstrom requires a reliable and reusable ignition source. To address both of these requirements, my team developed a GH2/GOx augmented spark igniter.

Among other components, the igniter features orifice fittings which ensure precise control over our injection areas and allow us to test the article at a wide range of Oxidizer/Fuel Ratio setpoints.

HEATSINK CHAMBER

While the long-term goal for Testbed
is to develop and manufacture a regeneratively cooled nozzle, our first iteration of the engine features a simple heatsink design that will allow us to validate our heat transfer model before we move on to the more complex cooling methods.

To ensure that the article can withstand the intense combustion temperatures, the nozzle features a special copper insert that transfers energy away from areas with the largest amount of heat flux.

Teeny-K Stand

As PURPL’s first test stand, Teeny-K was built for small engine testing. During the Spring 2025 campaign, it supported over 100 tests across three different combustion devices, with thrust levels ranging from 15 to 150 lbf.

Turbopump Gas Generator Hotfire Test

FLUID SYSTEM BUILD-UP

On the Teeny-K stand, I was responsible for specifying solenoid valves and pressure regulators using manufacturer flow curves, verifying SCFM capacity and droop margins for the stand’s mass-flow requirements.

Fittings were selected per standard interfaces—JIC 37°, NPT, and Swagelok—then tubing was bent, 37°-flared, assembled, and leak/pressure tested.

The resulting system features a clean, serviceable layout with proper support, labeling, and isolation points for rapid configuration changes.

DAQ SYSTEM ELECTRONICS

To reliably control our test stand and receive pressure and temperature data, I've designed a data acquisition system centered around a Labjack T7.

In its current form, it is capable of supporting up to 32 I/O channels split up between solenoid valves, pressure transducers, thermocouples, and a spark plug.

The system includes an E-stop circuit which allows for remote deenergization

To enhance the capabilities of our system, I am currently working on developing a custom signal conditioning PCB to replace some of the COTS units that are currently being used.

DAQ SYSTEM SOFTWARE

I developed a Python script to interface with a LabJack T7, reading pressure transducers and controlling solenoid valves and a spark plug during a hot fire test.

The script allows the user to either control the system manually or automatically via a sequencer system that reads from an external file to automate processes.

The program also features a real-time GUI displaying pressure readings, valve states, allowing the operator to easily monitor and adjust the system during the test.

CAVITATING VENTURIS

As our team prepared for a water-flow test of the injector, precise mass-flow monitoring became essential.

To address this, I designed, sized, and characterized a cavitating venturi. The venturi was fabricated from acrylic, allowing visual confirmation of cavitation.

Upstream pressure was measured, and mass flow was determined using a bucket-and-timer method, resulting in a discharge coefficient of 0.984. Future iterations will be made from stainless steel and include pressure taps at the inlet plane and in the throat, allowing cavitation to be assessed beyond visual observation.

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