How to determine the diameter of air ducts
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Help: Air flow rate is 200,000 cubic meters per hour, the design pressure of the pipeline is 10 kilograms. How can I determine the pipeline diameter?
1. Simulate it using software, such as HYSYS. 2. Calculate using relevant codes, such as the \"Code for Design of Gas Pipeline Engineering\", etc. However, the conditions you have given are quite general. First, it is necessary to know what kind of pipeline it is and what its purpose is Should the pipeline be vented? Wait, this way it’s more targeted. It is crucial to know the flow rate.
The poster needs to determine the flow rate; the value for air flow rate can take on a relatively wide range depending on the process requirements. Then the diameter of the pipe can be determined from the flow rate and velocity.
It can be considered as a compressed gas, and the pipe diameter can be calculated using a flow velocity of 8–10 m/s. This post was last edited by zyy1311 on 2008-3-12 09:59.]
The design pressure of the pipe is 10 kilograms. Assuming the maximum operating pressure is 6 kilograms and the flow velocity of air is 10 m/s, the inner diameter of the pipe is: D=26.6 mm. Therefore, a pipe with DN=32 is suitable; for extra safety, a pipe with DN=40 can be used.
The fluid velocity within the pipe can be determined by referring to the relevant fluid velocity values provided in chemical engineering design manuals. But it needs to be converted into the corresponding state. The pipelines for compressed air need to be converted.
I am very grateful for the help from everyone above. Here’s the specific situation: I am designing an air filter with a flow rate of 20 cubic meters per hour, a design pressure of 10 kilograms, a filtration precision of 5 microns, and a filtration area of 140 square meters. Now I need to determine the diameter of the filter inlet flange. The original design by the design institute was for a pipe diameter of DN600. But the diameter of my filter barrel is only 800, so I need to change the flange to DN200 or smaller. So I would like to ask if this is appropriate? Just now, a friend upstairs mentioned the issue of flow rate; so in such cases, what is a suitable flow rate? Of course, factors such as cost, affordability, and safety must all be taken into account.
Are you right? ? The owner requires a flow rate of 200,000 cubic meters per hour
Is a flow rate of 20 cubic meters per hour under standard conditions? The pipe diameter can be calculated based on a flow rate of 10 m/s. The calculation on the sixth floor is incorrect.
I’m sorry; I didn’t pay close attention to the unit. If it’s 200,000 cubic meters per hour, and assuming a flow rate of 10 m/s, the pipe diameter would need to be quite large. I hope someone with expertise can give me some advice.
Generally, for each type of medium, there is an empirical economic flow velocity, right? The original poster can use this value to determine the pipe diameter. I checked the chemical engineering design manuals, and for compressed gases (0.1–0.2 MPa), the typical flow velocity is 10–15 m/s; please refer to this value
Thank you. What is the appropriate diameter?
If the diameter of a single pipe is too large for transportation, then use two or more pipes in parallel; pipes are easy to obtain
The pipes are generally made of carbon steel; the flow rate is determined from manuals based on the properties of the medium, while the pipe diameter is determined by the flow rate and volume flow
I’d like to know what’s going on as well. I’ve seen designs for air ducts before, where the pressure is at atmospheric levels and the temperature is around 100 degrees. Based on the calculated flow rate and duct dimensions, the flow velocity can reach 30 m/s. I’m not sure why this is different from the economic flow velocity we usually encounter. Does that mean that sometimes, under certain design conditions, it is possible to refrain from using the economic flow rate?
The pipe diameter can be determined either based on the economic flow velocity or on the resistance loss per 100 meters. For compressed air pipelines, it is better to calculate it using the resistance loss: according to available data, for gases at 0.35–1.0 MPa, the value is 7 kPa per 100 meters; a pipe diameter of 600 MM falls within this range, so it is not advisable to make significant adjustments to the diameter. I won’t go into detail about the calculation of resistance loss, but it is important to pay attention to the conversion between standard cubic meters and operating volume. The operating volume is 22,524 m3/h, with a density of 11.48
One pipe must have been used:)
According to \"Design of Process Systems in Chemical Plants\", Chapter 4 \"Calculation of Process Parameters\", section 2.4 \"Allowable Flow Velocities\": For compressed air at 2–3 bar, the flow velocity is 16–32 m/s; for compressed air used for power purposes at 5–7 bar, it is 7–14 m/s in indoor facilities and 6–30 m/s in underground installations. For high-pressure gases (200–300 bar), the flow velocity is 5–10 m/s