Device for Pressure Difference Visualization

Device for Pressure Difference Visualization

Description:
I present to you a simple and effective device for visualizing pressure differences. This tool is ideal for educating students on the basic principles of fluid dynamics. The device uses hydrostatic pressure to compensate for external pressure changes. By observing the liquid level in the silicone tube, you can determine where pressure is higher or lower. Additionally, by measuring the difference in liquid levels within the tube, you can calculate the exact pressure difference.

Additional Materials Required:

• 6 mm silicone tubing

Assembly Instructions:

1. Print all components.
2. Insert the printed inserts into the corresponding slots. You may need to sand the edges of the inserts slightly to ensure a snug fit. When done properly, the components should hold together securely without glue.
3. Assemble the parts from Plate 1 and secure them using the longer axis from Plate 3.
4. Attach the leg (from Plate 6) to the back of the structure and secure it with the shorter axis from Plate 6.
5. Fix the silicone tube into the holders located on the front side of the structure.
6. Carefully fill the silicone tube with liquid, preferably using a syringe to avoid introducing air bubbles.
7. Connect the ends of the silicone tube to the objects or systems where you want to measure the pressure difference.

Great to hear you’ve got visuals to complement the explanation! Let me know if you'd like help with captions or integrating these visuals with the text. For now, here’s a more polished, standalone version of the description that could pair well with your visuals:

Experiment 1: Exploring Pressure Changes in a Tube

Setup

• Attach the constant cross-section tube (Plate 5) to the device.

Step 1: Blowing Through the Tube

• Blow air through the tube and watch the silicone pipe’s liquid levels.
  Observation: The pressure on the side closer to your mouth is lower than the opposite side.

Step 2: Adding a Balloon

• Attach a balloon to the far end of the tube and blow again.
  Observation: This time, the pressure on your side is higher compared to the previous test.

What’s Happening?

1. Pressure Gradient: To move air through the tube, you need a pressure difference. The side closer to your mouth will always have higher pressure when pushing air through.
2. Bernoulli Effect: Without the balloon, air speeds up significantly near your side of the tube, reducing the pressure due to Bernoulli’s principle (higher speed = lower pressure).
3. Balloon Influence: When the balloon is attached, the system requires a larger pressure gradient to fill the balloon with air. The speed difference along the tube becomes less significant, and the pressure gradient dominates, making your side of the tube higher in pressure.

Experiment 2: Observing Pressure Changes in a Venturi Tube

After observing pressure changes in a constant cross-section pipe, it’s time to explore how a Venturi tube behaves. Connect the Venturi tube (Plate 4) to the device and carefully blow into it. You’ll notice that the pressure difference is significantly larger compared to the constant cross-section pipe. In fact, if you blow too strongly, you might even force the liquid out of the silicone tube!

This phenomenon occurs because the air velocity increases dramatically in the narrower section of the Venturi tube. According to the Bernoulli effect, as the air speed increases, the pressure in the narrower section drops significantly. This is why the pressure difference in the Venturi tube is much more pronounced than in the constant cross-section pipe.