Flow rate design issue

The books specify the appropriate flow rates for different material pipelines; they are not chosen arbitrarily.

It’s fine, as long as the pump is strong enough. You have to pay for the electricity yourself. Be as happy as you want to be. :lol :lol :lol Of course, as long as there are no safety accidents. By the way, this is not a design issue; it’s an operational issue. This post was last edited by darliu on 2009-3-9 21:16]

Hehe, you’re conducting an experiment. It should be possible to achieve whatever size is desired. . . After all, it’s not running continuously; in actual production, things must be done in accordance with the standards. The regulations specify a maximum flow rate that must not be exceeded; otherwise, it can lead to safety hazards or accelerate the aging of the pipes.

Determining the pipe diameter isn’t just a matter of knowing the flow rate and the pump’s head pressure; it needs to be determined based on the process calculation data, as too few parameters have been provided by you. I’ll give you a design principle – it’s more meaningful to do it by yourself. Design of process pipeline diameter: 1. The pipeline design must meet the basic requirements imposed by the process. Its flow capacity should be determined based on the maximum flow rate of the medium under normal operating conditions; the maximum pressure it can handle should not exceed the values permitted by the process, and its flow velocity should fall within the safe range determined by the properties of the medium. 2. Weigh construction investment and operating costs comprehensively. Piping for a petrochemical plant usually accounts for about 20% of the total investment. As the pipe diameter increases, not only does the wall thickness and weight of the pipe increase, but so does the weight of the valves and other components installed on the pipe. Additionally, more insulation material is required, which raises the costs as well. Therefore, in pipeline design, it is generally advisable to choose the smallest possible pipe diameter while still maintaining an acceptable pressure drop; this is especially true when determining the diameter of alloy pipes, in order to reduce costs. As the pipe diameter increases, the flow velocity of the medium rises, resulting in greater frictional resistance. This leads to increased costs associated with materials and energy consumption, as well as higher operating expenses. Therefore, when determining the pipe diameter, a best value is obtained by comprehensively weighing the investment and operating costs. 3. Different operating conditions. Different fluids require different flow rates depending on their physical properties, state, and operational requirements. The liquid frictional resistance during annual operation is high, so a lower flow rate should be selected. For pipes that allow for a smaller pressure drop, such as gravity-fed pipes at atmospheric pressure and the inlet pipes of pumps transporting liquids at their bubble point temperature, a lower flow rate should be selected. For pipes that allow for larger pressure drops or have lower fluid viscosity, a higher flow rate should be used first. To prevent phenomena such as pipeline erosion, wear, vibration, and noise caused by excessive ring flow velocity, the liquid flow rate should generally not exceed 4 m/s ； The gas flow velocity generally should not exceed 85% of its critical velocity ； The maximum flow velocity under vacuum does not exceed 100 m/s ； For fluids containing solid particles, the flow rate should not be too low, so as to prevent the solids from depositing inside the pipes and causing blockages, but it also shouldn’t be too high, to avoid accelerating pipe wear or erosion. 4. In the case of the same medium in different pipes, even when the flow rate and pipe length are identical, the pressure drop across the pipes can still vary significantly. Therefore, when designing pipelines, if the allowable pressure drop is the same, a lower flow velocity should be selected for media with low flow rates, while a higher flow velocity can be used for media with high flow rates. 5. After selecting the pipe. Standard pipes made of composite materials should be used; pipes with diameters of DN32, DN65, and DN125 are not recommended. 6. The relationship between the volumetric flow rate, flow velocity of the medium in the pipeline and the pipe diameter shall comply with relevant regulations. 7. These requirements apply only to Newtonian bodies.

The flow rate in the pipeline is not chosen arbitrarily. First, you need to consider the material of the pipeline and the properties of the material being transported; only then can you determine the appropriate flow rate based on your budget considerations. Since a higher flow rate results in greater resistance, the costs increase significantly once a certain flow rate is exceeded