Hi All
I have an environmental specification for a PLC which I'm struggling to interpret.
Vibration
Functional Stress5Hz to 9Hz
Continuous1.7mm amplitude
Occasional3.5mm amplitude
Withstand10Hz to 150Hz
Acceleration0.1g
Endurance10Hz to 150Hz
Acceleration0.5g
What are the definitions of...
http://www.researchgate.net/publication/258022527_A_comparative_overview_of_large-scale_battery_systems_for_electricity_storage/links/02e7e526b305a9b655000000 has some figures on p786. Capital cost of flywheels is US$400-800/kWh.
Vendor surge parameters are usually set very conservatively. There can be a lot to be gained (in terms of available operating range) by surge testing.
We prefer to throttle on the suction but it is also possible to throttle the discharge. I don't know why you'd need to do both at the same time...
I have often wondered why a rotor will bow in horizontal storage.
Doesn't this suggest room-temperature creep exists in stainless steel?
I'm pretty sure it doesn't.
Aerogel looks like a good option, similar performance to microsopheres but perhaps easier to handle.
The boiloff is around 5% per day, corresponding to around 20 watts of heat inleak.
What's a good target, 1 or 2% per day?
Level measurement is another challenge. Capacitance gauges seem to be...
It's great you're all so interested in microspheres but what I actually need help with is the design of inner vessel supports and piping feedthroughs for minimal heat transfer.
Due to the small size of the vessel (approx 1" vacuum space) there is no room to do anything intricate.
Just checked the vacuum and it's less than 1 micron (gauge is reading 0.000 Torr).
I couldn't get it below 80 microns warm so clearly there was water vapour which is now frozen. I thought this might be an issue with the microspheres as they were sitting around in our store for a few months...
They have an isostatic crush pressure of around 300 psi. I've got a paper on tests with microspheres in vacuum insulated flexible hoses, at extreme bend radii there was some loss of vacuum due to crushing but for vessels they are more than strong enough.
For me they are great because I can...
Microspheres are a ligitimate vacuum insulation with many advantages over MLI and only slighty worse performance.
My problem with MLI is that all information about its application is proprietary.
http://www.techapps.com/microsphere-insulation-programs.html
Thanks iainuts
That's the problem I'm finding - nobody wants to give away their secrets.
The book looks good, I've just ordered it.
The tank is around 27" OD so there isn't enough room in the vacuum space to do anything complicated.
Mind if I ask what your experience in this is?
Hi All
I'm designing an LNG vessel as an onboard fuel supply for natural gas powered trucks.
First prototype is performing ok but there is plenty of room for improvement. Mainly excessive heat inleak throught the feedthroughs and inner vessel supports.
Incidentally it's insulated with 3M glass...
