How to calculate the flow rate under superheated steam conditions?
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It is known that the steam flow rate is 5 t/h, the steam pressure is 0.8 MPa (gauge pressure), and the temperature is 300 degrees. The delivery pipeline has a DN65 diameter (with an inner diameter of 65 mm). Could you please calculate the flow velocity of the steam under these conditions? Thank you! There is another question: in the tables in the book, the density corresponding to the temperature and pressure of superheated steam should refer to the density under operating conditions, right?
This post was last edited by yggswl on 2016-12-24 at 13:39. I did the calculations myself, and the flow velocity under those operating conditions is around 120 meters per second. How can there be such a high flow velocity?
The density corresponding to the temperature and pressure of superheated steam should refer to the density under the operating conditions. For superheated steam, the flow velocity ranges from 20 to 40 m/s for pipe diameters of DN100 or less; higher flow velocities result in greater pressure drops. The pressure drop can be calculated in accordance with the SH3035-2007T Guidelines for Selecting Pipe Sizes for Process Units in Petrochemical Enterprises
My calculation is around 100.6 meters per second
This post was last edited by yggswl on 2016-12-24 at 16:13. There is a gas storage tank with a capacity of 10 cubic meters, operating at a pressure of 0.8 MPa. The air compressor has a flow rate of 3.5 cubic meters per minute (this refers to the inlet flow rate of the compressor, under standard conditions), also at a pressure of 0.8 MPa. There is a switch valve located after the gas storage tank. The pipeline has a diameter of DN65, and its length is 50 meters. At the end of the pipeline, there are 60 nozzles with a diameter of 3 mm, and each nozzle operates for 7 minutes at a time. Could you please calculate the compressed air flow rate in the pipeline, the nozzle flow rate, and the pressure maintained at the end of the pipeline? When the nozzle is in operation and the valve is fully open, how much pressure will remain in the air tank after 7 minutes? Thank you all for helping to calculate it!
Isn’t this pipe diameter a bit small?
According to ASPEN calculations, the value is 120 m/s. Is this outlet connected directly to the atmosphere? Otherwise, the flow velocity is too high
This post was last edited by goldliyang on 2017-3-17 09:16. The density corresponding to superheated steam has been determined; the mass flow rate divided by density gives the volume flow rate, and dividing that value by the cross-sectional area yields the steam flow velocity. Excessively high flow rates lead to increased pressure loss, greater noise, accelerated pipe wear, and reduced ability to withstand load fluctuations. The pipe diameter needs to be increased.