Testing Vortex Generators in Flight — Stall Speed Drop & Real-World CFD Results скачать в хорошем качестве

Testing Vortex Generators in Flight — Stall Speed Drop & Real-World CFD Results

Today we’re flight-testing new vortex generators (VGs) and comparing real-world stall performance against CFD (computational fluid dynamics) predictions. We’ll test stall speeds clean and with flaps, evaluate handling, and dive into the CFD data that guided VG placement — down to the thousandth of an inch. The goal: confirm how much lift, drag, and stability change after adding properly positioned VGs to a high-lift laminar wing. This flight shows real stall behavior, recovery altitude, and in-flight calibration of the Garmin attitude indicator, followed by a detailed post-flight CFD analysis explaining why the changes work. Timestamps: 00:00 – Takeoff & Overview Testing new VGs installed on the wing; climb to 5,000 ft AGL. 00:36 – First Stall Series Initial stall test clean configuration — onset, break, and recovery. 01:03 – Stall Results Observed stall around 48 mph vs 58 mph prior to VG install. 200 ft loss, solid recovery. 01:47 – Flap Configuration Test Flaps down, slower power-on stall; results slightly better than expected. 02:26 – Dive Test & Trim Change High-speed dive to 8,500 ft reveals noticeable trim and attitude change. 02:43 – Flight Attitude Shift Negative tail pressure required; new pitch behavior under same conditions. 03:13 – CFD Validation in Flight Speed gain of ~2 mph at same density altitude confirms CFD accuracy. 03:53 – Garmin Attitude Indicator Recalibration Adjusting for changed flight attitude; discussion of horizon alignment. 04:40 – Pattern & Landing Behavior Revised approach speeds — slower, more stable, but with steeper sight picture. 05:16 – Touchdown Observations Landing noticeably softer; approach profile recalibrated. 05:53 – Flaps-Down Takeoff Test Testing VG impact on lift-off characteristics and acceleration. 06:22 – Short Takeoff & Climb Performance Reduced takeoff roll; similar lift with less power. Substantial improvement. 07:35 – Post-Flight Analysis Transition to CAD/CFD environment — explaining the test setup and methodology. 08:00 – Wing Model & VG Placement Airfoil modeled to thousandths of an inch; testing various VG chord locations. 09:00 – Velocity & Pressure Visualization CFD plots show airflow acceleration, pressure zones, and boundary layer control. 10:16 – Vortex Pattern & Trailing Edge Effect Visualization of swirl persistence to aileron; optimal placement found. 11:15 – Lift vs Drag Data Comparing sections with/without VGs — measurable lift gain and drag reduction. 12:01 – Quantitative Results ~1 lb lift increase per section; 0.4 lb drag increase mitigated by improved efficiency. 12:45 – Bubble Analysis & Flow Separation Identifying low-velocity bubble and how VGs stabilize it near 3.5% chord. 13:35 – Final Placement Rationale Settled location captures slow air before separation without excessive drag. #Aviation #FlightTest #ExperimentalAircraft #STOL #BushFlying #CFD #Aerodynamics