Hello everyone,

I am going to use a the pressure differential to calculate flow. I am having a hard time understanding how exactly to execute Bernoulli's equation. I assume the raw sensor data should be converted into inAq or inHg. Then Subtract the two to get the pressure Delta. This is where I get confused. How do I account for density of whatever I'm using to measure (water/mercury)?

I see in the equation where density of air is taken into consideration, but just cant fully wrap my mind around it. I have searched all over the web, but still don't quite get it. If someone could give me an example I would greatly appreciate it. Thanks!