[pure-silver] Re: Sink Decisions and Waterproofing

Peter Badcock a écrit :

Claudio,
I agree with you that it is a good idea to lower your vent tube. This is how I placed mine - just above the trays. I also have a sheet of air blowing across There is one other area I can suggest you change with your ventilation tube. As you are extracting the air from one end of the pipe, unless you have an extremely high negative pressure ( i.e. vacuum) at the end of the tube, the relative pressure drops between each hole across the tube will result in radically different flow rates at one end of the tube compared to the other end. To get around this I constructed a symmetrical design (using a Y shaped splitter in the middle see http://www.users.on.net/~tallowood/images/DSCN0845_sink%235.jpg <http://www.users.on.net/%7Etallowood/images/DSCN0845_sink%235.jpg> ). Additionally, and this is just as important, in my latest prototype (not the one shown in the photo), I changed the continuous slot design into multiple diagonal slots that became larger towards the end of the two pipes. An ASCII art attempt gives the following
| |
| |
| |
| |
/ /\ \
----------------------------- -- ------------------------------
| /// // // / \ \\ \\ \\\ |
| /// // // / \ \\ \\ \\\ |
-------------------------------------------------------------------
I used a spirometer (i.e. a flow meter that you can see in the photo) to tune the hole sizes, since there are no easy formulae for calculating the fluid dynamics in this highly non-typical situation (I didn't want to resort to finite element analysis!)
regards
Peter 


Sorry to reply you so late.
I like your design, sounds good.
Is a spirometer a common tool in your darkroom ?!?!  :-)

Regards,

--

Claudio Bonavolta
http://www.bonavolta.ch


=============================================================================================================
To unsubscribe from this list, go to www.freelists.org and logon to your 
account (the same e-mail address and password you set-up when you subscribed,) 
and unsubscribe from there.

Other related posts: