Pressure scanning valves are not just used but are crucial core test equipment in advanced research within fluid 

dynamics, aerospace, and power engineering at universities.

1. Why are They Used in University Research?

The core advantage of a Pressure Scanning Valve (or Electronic Scanning Pressure system) is its ability to measure 

pressure at dozens or even hundreds of points synchronously, at high speed, and with high precision. It offers a 

revolutionary improvement over traditional mechanical scanivalves. Universities favor them for:

High Spatiotemporal Resolution: They can capture transient phenomena (e.g., turbulence, rotating stall, 

combustion instability) vital for understanding flow mechanisms.

High Accuracy & Efficiency: Automated data acquisition significantly reduces experimental duration and human 

error.

Support for Complex Models: They are the only economically feasible option for complex models (e.g., wings, 

turbomachinery) with many pressure taps.

Synchronization with Other Techniques: They integrate easily with PIV, hot-wire anemometry, and force sensors 

for multi-dimensional flow field data.

2. Applications in University Experiments

They are widely used in these typical university experiments:

Aerodynamics Tests (Wind Tunnels):

Measuring airfoil/wing surface pressure distribution to determine lift, drag, and moment coefficients.

Studying inlet/compressor system performance and flow separation.

Building aerodynamics for measuring wind pressure distribution on structural models.

Turbomachinery Experiments:

Performance studies of compressors/turbines, assessing stage efficiency, pressure ratio, and losses.

Research on rotating stall and surge, requiring the scanner's high-speed sampling to capture dynamic processes.

Combustion & Propulsion Experiments:

Combustion instability research, analyzing pressure pulsations in combustors.

Pressure field monitoring in engine inlet/exhaust systems.

Hydrodynamics Experiments (Water Tunnels):

Measuring pressure distribution on underwater vehicles to study cavitation inception and fluid noise.

3. Purpose of the Test Data

The data quantitatively supports:

Performance Validation:

Verifying theoretical models and CFD simulations by comparing measured pressure distributions and loss 

coefficients—a primary research goal.

Evaluating design alternatives by comparing pressure distributions for different geometries.

Flow Structure & Mechanism Research:

Identifying flow separation, transition, and vortex structures by analyzing pressure distribution and spectra.

Analyzing unsteady flow mechanisms (e.g., rotor-stator interaction, flutter) using high-frequency data.

Structural Loads & Safety Analysis:

Identifying dynamic loads (e.g., building buffeting, wing gusts) from pulsating pressure data.

Fault diagnosis and prediction by monitoring abnormal pressure changes to warn of stall or surge.

4. Specific Implementation Details

A typical example: "Aerodynamic Characteristics of an Airfoil in a Low-Speed Wind Tunnel."

Preparation:

Model: An airfoil model is fabricated with a row of pressure taps along the chord on upper and lower surfaces.

Tubing: Identical, small-diameter tubes connect each tap to a scanner channel. Consistent tube length/diameter 

ensures uniform pressure response.

Calibration: Before the test, all scanner channels are calibrated using a precision reference pressure.

Procedure:

The model is installed in the wind tunnel test section.

Flow speed and angle of attack are set.

Once flow is stable, the scanner is triggered via software, measuring all channels almost instantaneously.

The process repeats at different angles of attack.

Data Analysis:

Pressure Coefficient (Cp) Calculation: Cp is calculated for each point using local static pressure, freestream static 

pressure, and dynamic pressure.

Visualization: Cp values are plotted against chordwise position, creating the classic airfoil pressure distribution 

chart.

Aerodynamic Force Calculation: The lift coefficient is calculated by integrating the Cp distribution over the 

airfoil surface.

Flow Analysis: A Cp plateau often indicates flow separation. Spectral analysis of unsteady pressure reveals 

phenomena like vortex shedding.

In summary, the pressure scanning valve is a key tool enabling university research to progress from qualitative 

flow observation to quantitative flow analysis. The high-quality data it provides is foundational for validating 

theories, revealing underlying mechanisms, and optimizing designs, greatly advancing fluid mechanics and 

related disciplines.