Johaneev
Sheelam

Phase-one development of a linear O₂/C₂H₄ detonation tube test platform — a calculated stepping stone toward full RDE implementation — designed to experimentally validate a physics-based detonation model developed in-house. The program covers propulsion design, structural analysis, instrumentation, test stand construction, safety system architecture, and operational procedures from PDR through hot-fire. Annular ridge geometry (cosine profile, 43.8% blockage ratio, 10 ridges) drives deflagration-to-detonation transition. The numerical analysis phase is complete and published in AIAA proceedings.

The coupled Euler–finite-rate chemistry framework captured detonation-scale wave propagation within 2–3% of classical CJ velocity predictions. ANSYS CFX 3D simulations corroborated the reduced-order MATLAB solver's pressure-rise trends to within 14% after ignition kernel repositioning. BlastFOAM/OpenFOAM simulations of the ridged tube geometry (150k-cell full-tube mesh, trueRidged_150k_fullTube) provided direct pressure-field corroboration and softly drove annular ridge design decisions. Structural screening confirmed 17-4PH steel geometry supports the detonation environment with significant margin — providing quantitative justification for hardware fabrication and staged experimental testing.

Pressure contour from BlastFOAM simulation of the full ridged-tube geometry (150k cells, trueRidged_150k_fullTube). The reacting front propagates left-to-right through the annular ridge array; pressure scale runs 1.0×10⁵ Pa (blue) to 2.2×10⁶ Pa (red). Cross-validated against the published MATLAB HLLC solver result.

BlastFOAM / ParaView · trueRidged_150k_fullTube.foam · Pressure field [Pa] · t = 2.75×10⁻⁴ s

Structural screen applied DAF = 2.0 (single-pass step-load) with ridge stress concentration K_t = 1 + 2.75 × blockage. Peak ridge at x = 0.83 ft (blockage = 0.435) produced K_t = 2.20 and peak σ_vm = 29.5 MPa — well within the 275.7 MPa H1150 allowable. All 400 nodes clear yield, allowable, and UTS checks. Thermal penetration depth 0.042 mm (0.2% of wall) over 0.35 ms event duration confirms negligible thermal influence on structural margins for the single-shot screen.

Cumulative exceedances (DAF = 2.0) · 0 nodes yield, 0 exceed S_allow, 0 exceed UTS

Global peak gain histories · G_turb peaks 1.528× · G_p peaks 1.095× · steady-state ≈1.41× / 1.07×

Dynamic ridge activation snapshots · ridge activation, G_turb, and G_p spatial profiles at t = 0.001, 0.089, 0.176, 0.262, 0.350 ms

Gain at leading front · G_turb front peak 1.329× · G_p front peak 1.059× · periodic ridge-encounter signature visible

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[ Photo — Test Stand Assembly · Pending ]

• Led test stand design as primary decision-maker — owned all hardware decisions across mechanical, electrical, and propulsion subsystems. Team of four engineers with supporting roles.
• Developed the custom MATLAB 1D HLLC solver from scratch: CJ/ZND theory, Euler equations, operator-split Cantera chemistry, shock/detonation front tracking, and Lamé structural screening — all integrated into a single coupled framework. Published.
• BlastFOAM/OpenFOAM used for direct reacting-flow corroboration of the ridged tube geometry (150k-cell full-tube mesh). Cross-validated against MATLAB solver; results drove annular ridge profile selection.
• ANSYS CFX used for 3D multidimensional corroboration: k-ω turbulence, shear-layer development, and confinement behavior not resolvable in 1D. Identified and resolved secondary wave interference via ignition kernel repositioning.
• Designed regenerative cooling architecture, CDI high-pressure ignition system, and suppressor/wave-capture system for post-detonation safe depressurization — no vacuum chamber infrastructure.
• Full operational pipeline: PDR, CoDR, safety board reviews, formal experimental SOP authored for every stage of the test campaign. Hot-fire scheduled Aug 2026.

High-speed data acquisition architecture for reactive propulsion test environments, where signal fidelity, synchronization, and EMI immunity are mission-critical. Designed around National Instruments PXI hardware, with LabVIEW acquisition feeding into a MATLAB post-processing and averaging pipeline.

• Designed sensor routing and channel synchronization for multi-sensor detonation events at high dP/dt transients
• EMI shielding architecture across ignition, sensor, and power lines to protect signal integrity during reactive events
• Live telemetry visualization with automated post-processing averaging for pressure trace validation
• All sensor channels active — thermocouple, dynamic pressure, and structural instrumentation fully integrated

Founded and led Agricultural Unmanned Aerial Systems — an independent engineering operation designing, fabricating, and deploying UAV platforms for agricultural applications. Four generations of platform development, 15–20 operational units fielded in real-world deployments, demonstrating full-lifecycle engineering ownership from first-principles design through sustained operational use.

• Applied aerospace vehicle design principles to payload capacity, endurance optimization, and operational reliability under real field constraints
• Owned full lifecycle: conceptual design → aerodynamic analysis → propulsion selection → fabrication → flight test → iterative redesign
• Four generations of evolution driven by operational data and field failure analysis
• Managed transition from prototype to production-intent platforms suitable for sustained field use

Electrical engineering internship at Canyon AeroConnect focused on avionics hardware integration, electronics validation, PCB-level debugging, and manufacturing workflows for flight-critical aerospace systems. Work includes schematic review, board bring-up, signal integrity analysis, hardware reliability improvement, and supplier/manufacturing coordination through to production release.

• Redesigned PCB filtered connector architecture to unfiltered connectors with discrete capacitor pre-stage to resolve a component lead-time constraint — maintained EMI compliance and impedance matching throughout. Design approved and released to manufacturing.
• Schematic review, bring-up testing, and hardware failure debugging across avionics board-level systems
• Generated ECOs, ECRs, EDRs, and Problem Reports while coordinating with suppliers, QA teams, and manufacturing contractors

The RDE program is the direct continuation of the Phase I detonation tube work. The detonation tube was built to prove detonation initiation, wave characterization, and model fidelity — providing the experimental and analytical foundation required to design a full annular rotating detonation engine running LOX/kerosene. Phase II is now underway with simulation, injector characterization, and CFD mesh work in parallel.