Is My Flow Laminar or Turbulent at Re= 200,000?

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The discussion centers on calculating the Reynolds number for an automotive AC suction line, which is found to be around 200,000, indicating turbulent flow according to standard equations. Despite this, the original poster questions whether the flow could still be laminar due to potential vibrations affecting the flow characteristics. Experts clarify that while the Reynolds number suggests turbulence, it doesn't guarantee that the flow is turbulent throughout the entire system, especially in short pipes. The conversation emphasizes the complexity of flow dynamics in automotive applications, where theoretical calculations may not fully account for real-world conditions. Ultimately, the Reynolds number can still be applied using turbulent flow equations for practical purposes.
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I am calculating Reynolds number for a automotive ac suction line with 16mm Id 300kpa and 10 deg C and 230 kg/hr. I am getting around 200,000. I think I got laminar flow, but the equation says turbulent. greater than 10,000. dynamic viscosity is my most questionable variable. i checked and double checked all my SI units. Anybody know if this Reynolds number is in the reasonable range?
 
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Sometimes when you are working with cars, although the flow might be theoretically laminar, we have to account for the vibrations that will most likely make it turbulent.

You can still use the Reynolds number you obtained but with the turbulent equation.
 
What makes you think your flow is laminar?

At any rate, for pipe flow, the diameter Reynolds numbers typically quoted for the onset of turbulent don't mean that the flow is instantly turbulent. It merely means the flow is unstable and will eventually become turbulent. If your tube is quite short, you could have extraordinarily high diameter Reynolds numbers and still be laminar for at least a short distance downstream.
 
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