calculation problem

jibreel · October 22, 2013, 05:34

i analyze a flow passage.
but the problem is energy at the outel comes greater then energy at inlet please tell me what to do.
i gave parameters as
velocity inlet 3m/s
pressure outlet 20000pa

value of inlet pressure calculated is too small that it cannot satisify the bernulli equation.
plz help me

Vidyanand Kesti · October 23, 2013, 06:08

how did you got this 20000Pa ,is it pressure drop or gauge pressure or absolute pressure?

jibreel · November 7, 2013, 06:54

Actually i want to calculate the energy loss in half symmetic nozzle with a half sphere inserted in flow to produce restriction
inlet condtions
Din=16m
Vin=3m/s
Outlet condtion
Dout= 6.5m
Pressure out=20000pa (just a guess just to see what will be the value of inlet pressure for this outlet pressue but i think is whould be large enough to satisify the conservation of momentum.)
i got following results at cerntral axis
Vout=18m/s
Pressure inlet=186900Pa
Plz tell me how to calculate the energy loss due to (friction, flow recirculation etc.)

October 22, 2013, 05:34	calculation problem	#1
jibreel New Member Ahmad jibreel Join Date: Oct 2013 Posts: 6 Rep Power: 12	i analyze a flow passage. but the problem is energy at the outel comes greater then energy at inlet please tell me what to do. i gave parameters as velocity inlet 3m/s pressure outlet 20000pa value of inlet pressure calculated is too small that it cannot satisify the bernulli equation. plz help me

November 7, 2013, 06:54	calculation problem	#3
jibreel New Member Ahmad jibreel Join Date: Oct 2013 Posts: 6 Rep Power: 12	Actually i want to calculate the energy loss in half symmetic nozzle with a half sphere inserted in flow to produce restriction inlet condtions Din=16m Vin=3m/s Outlet condtion Dout= 6.5m Pressure out=20000pa (just a guess just to see what will be the value of inlet pressure for this outlet pressue but i think is whould be large enough to satisify the conservation of momentum.) i got following results at cerntral axis Vout=18m/s Pressure inlet=186900Pa Plz tell me how to calculate the energy loss due to (friction, flow recirculation etc.)

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October 23, 2013, 06:08		#2
Vidyanand Kesti Member vidyanand Join Date: Nov 2011 Location: bangalore,india Posts: 66 Rep Power: 17	how did you got this 20000Pa ,is it pressure drop or gauge pressure or absolute pressure?