ptonsparky
Tom
- Occupation
- EC - retired
It will be interesting to see how they remedy this. Turkey is a long ways away and startup is in two weeks.
Agitator motors
- Thread starter ptonsparky
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It will be interesting to see how they remedy this. Turkey is a long ways away and startup is in two weeks.
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
One solution would be a VFD to change the shaft speed. Not cheap, but could fit the time frame if a speed reduction would do the job.
ptonsparky
Tom
- Occupation
- EC - retired
Fortunately it is not my problem,
Four units. Two sharing the same conduit. All in PVC. Industrial control panel by others. Not my problem. Not my problem. Not my...:happysad:
Four units. Two sharing the same conduit. All in PVC. Industrial control panel by others. Not my problem. Not my problem. Not my...:happysad:
- Location
- San Francisco Bay Area, CA, USA
- Occupation
- Electrical Engineer
More than that. 1.2 cubed is 173%. But it's a great point. 11kW motor, 19kW load...
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
Sorry, wrong numbers.
- Location
- San Francisco Bay Area, CA, USA
- Occupation
- Electrical Engineer
People in Turkey are now suffering from ISIS attacks, they probably have a lot on their minds right now...
And the only solution I can think of is to get those props off and have them trimmed on a lathe machine, i.e. smaller diameter!
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
That might work in a pinch, but it risks screwing up the fluid dynamics.And the only solution I can think of is to get those props off and have them trimmed on a lathe machine, i.e. smaller diameter!
- Location
- San Francisco Bay Area, CA, USA
- Occupation
- Electrical Engineer
Not to mention taking on responsibility for performance of a mechanical device...
See above, "Not my (his) job..."
Years ago I used to tackle projects like that, but I have been burned too many times. I was just trying to help (usually so I could get paid), but when my "fix" didn't work, suddenly everyone FORGETS that it didn't work BEFORE I touched it and it becomes MY fault. No thank you...
Oh, and when it DID work? No extra cash...
- Location
- Massachusetts
Sadly I have found that no good deed goes unpunished is a truism.
- Occupation
- Licensed Electrician
That reinforces my opinion that 85% of the time when someone has a
problem with a motor the problem is not the motor.
It's been fun following this story. Keep up with the updates please.
Yep. BTDTGTT thing!
If the designers thought an 11kW device does the stirring but the device installed is 19kW, I wouldn't be wrong if I trim the props so it just delivers 11kW!
Same amount of work? Or are there extraneous bits re stirring manure slurry that I missed there?
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
Yep. BTDTGTT thing!
If the designers thought an 11kW device does the stirring but the device installed is 19kW, I wouldn't be wrong if I trim the props so it just delivers 11kW!
Same amount of work? Or are there extraneous bits re stirring manure slurry that I missed there?
It may seem that way on the surface, but the key performance element for the application is not how much power it draws but how much stirring it does.
By casually trimming the prop (giving it a bowl haircut) instead of changing the pitch you risk at best getting less stir per kW and at worst having problems with cavitation or other serious local conditions.
I am not saying anything bad will for sure happen, just that I am not the person to say that it won't!
ptonsparky
Tom
- Occupation
- EC - retired
The idea of these pits and stirring machines is to keep the solids in suspension until it is run through a separator and compression cycle. Literally the stuff is squeezed out of it until the solids can be reused in the loafing area. The liquid is recycled to flush the barns again. Result is fertilizer, bedding and little to no additional water for the flush. More than I know.
- Location
- San Francisco Bay Area, CA, USA
- Occupation
- Electrical Engineer
"... loafing area..."
I don't want to know...?
I don't want to know...?
The power requirement of the agitator depends on the pattern of flow of the medium around the impeller. If it is a turbulent flow, its power requirement is low. To ensure it, the Reynolds number should be greater than 10,000.
Reynolds number=(impeller dia in ft squared)*(revolutions per hour)*(density of medium in pound per cubic ft)/(viscosity of medium in lb/hr-ft)
Reynolds number=(impeller dia in ft squared)*(revolutions per hour)*(density of medium in pound per cubic ft)/(viscosity of medium in lb/hr-ft)
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
there are some interesting water recycling systems for large beef and pork operations.
gadfly56
Senior Member
- Location
- New Jersey
- Occupation
- Professional Engineer, Fire & Life Safety
The typical threshold for turbulence is an Re of 2,300. Full turbulent flow is at 4,000. At least, so say Bird, Stewart, and Lightfoot.
BTW, your units don't cancel. You've got L3 left over. I think you may have the wrong units for viscosity.
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
I think that the appropriate units for viscosity are pound-seconds per foot squared.
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