Project Overview
This project focused on designing and developing a custom thrust validation test system for a contra-rotating dual BLDC propulsion unit. The goal was to validate supplier-provided thrust vs. current performance data and gain deeper insight into how system-level variables influence propulsion efficiency.
Given the complexity of contra-rotating systems, where thrust output depends on the interaction between multiple rotating stages, independent validation was required to ensure performance accuracy and to inform design decisions for optimal efficiency.
Design & Experimental Setup
I designed and built a controlled thrust test stand that enabled independent power control of the upper and lower motors within the contra-rotating assembly. This allowed isolation of variables and detailed analysis of how thrust output depended on current distribution between stages.
The system was instrumented to measure total thrust output under varying operating conditions, while maintaining a modular configuration that supported rapid changes in test parameters. The setup was designed to ensure repeatability and consistency, enabling reliable comparison across multiple configurations.
Testing was structured as a parametric study, where key variables influencing propulsion performance were systematically varied. These included:
-
Propeller pitch
-
Propeller diameter
-
Spacing between contra-rotating propellers
-
Current distribution between upper and lower motors
This approach allowed detailed characterization of how each parameter influenced thrust generation and overall system efficiency.
A key objective was to validate a CFD-predicted ~30% improvement in thrust efficiency, achieved through optimized propeller configurations. Experimental results confirmed this improvement and provided further insight into the conditions under which these gains were realized.
To ensure safe operation during extended testing, I monitored motor temperature and thermal behavior under varying load conditions. This was critical for identifying safe operating limits and understanding performance trade-offs between efficiency and thermal constraints.
All test data was recorded and used to generate performance curves and comparative plots, enabling direct evaluation of system behavior across configurations. These datasets supported selection of optimal operating points based on:
-
Thrust output
-
Power consumption
-
Efficiency
-
Thermal stability
Results & Impact
The test system provided a reliable platform for both validating supplier data and optimizing propulsion performance. By combining controlled experimentation with data-driven analysis, the project enabled identification of an optimal configuration tailored to system-level requirements.
This work directly informed propulsion design decisions, improving system efficiency and ensuring confidence in both component performance and overall system integration.
Key Takeaways
-
Independent testing is critical for validating and refining supplier-provided performance data
-
Contra-rotating propulsion systems require analysis of interdependent variables and stage interactions
-
Parametric testing enables systematic optimization across multiple design variables
-
Thermal behavior must be considered alongside performance in high-power systems
-
Data-driven analysis is essential for selecting optimal operating conditions