QUESTION - 4: You are conducting an experiment using a Pitot-static tube to measure the airflow velocity over a model wing. Describe the calibration process and how you would ensure that your measurements are free from errors.

To ensure accurate measurements with a Pitot-static tube, follow these calibration and error-reduction steps:<br /><br />1. **Calibration Process:**<br /> - **Static Pressure Calibration:** Use a known static pressure source to verify the static port readings. Adjust if necessary to match the reference.<br /> - **Dynamic Pressure Calibration:** Connect the Pitot tube to a wind tunnel or airflow source with a known velocity. Measure the dynamic pressure and compare it to theoretical values calculated using Bernoulli's equation. Adjust the instrument as needed.<br /><br />2. **Error Reduction:**<br /> - **Alignment:** Ensure the Pitot-static tube is aligned correctly with the airflow to avoid angular errors.<br /> - **Temperature and Density Corrections:** Account for variations in air temperature and density, which can affect pressure readings.<br /> - **Leak Checks:** Regularly inspect the system for leaks that could alter pressure readings.<br /> - **Zeroing Instruments:** Before each measurement session, zero the pressure transducers to eliminate offset errors.<br /> - **Environmental Conditions:** Conduct measurements in stable environmental conditions to minimize fluctuations in readings.<br /><br />By following these steps, you can ensure that your Pitot-static tube measurements are accurate and reliable.