Article 30291 of alt.solar.thermal: Path: news.misty.com!not-for-mail From: nicksanspam@ece.villanova.edu Newsgroups: alt.solar.thermal Subject: Re: How we hijack this group???? and moderate it?? Date: 6 Apr 2008 15:03:43 -0400 Organization: Villanova University Lines: 47 Message-ID: References: <47F78D98.8E5ED130@iedu.com> <47F8E417.A7A79800@iedu.com> NNTP-Posting-Host: acadia.ece.villanova.edu X-Trace: max.inside.misty.com 1207505040 4351 153.104.44.130 (6 Apr 2008 18:04:00 GMT) X-Complaints-To: abuse@misty.com NNTP-Posting-Date: Sun, 6 Apr 2008 18:04:00 +0000 (UTC) Xref: news.misty.com alt.solar.thermal:30291 Morris Dovey wrote: >I'm inclined to agree. The entire width of the panel should be >filled with drums - and I'm inclined to better like smaller drums >stacked two-high. Or a stack of shallow trays supporting water in poly film ducts. >> We can do this with less ceiling mass and perfect room temp control, with >> more glazing. Collecting (8h(70-20)+16h(50-20))49 = 43.1K Btu at 5390 Btu/h >> with 96 ft^2 of glazing makes T = 238+10.8K/96 = 126 F on average. With lots >> of airflow and mass surface, we only need 23.5K/(126-50) = 309 Btu/F, eg >> 309 pounds of water in shiny trays under a ceiling. > >Shiny trays under the ceiling sounds pretty kinky - I'm not sure >it'll catch on here in the heartland. It could be a high price to pay, aesthetically-speaking. (Doesn't Frank Gehry live in the heartland?) >... 309 pounds of water in them is only about 38 or 39 gallons - roughly >70% of the capacity of a single 55 gallon drum. Yes, with an infinite surface, or more water, with less surface: 20 FOR NTRAYS = 1 TO 4 30 A=4*8*NTRAYS'one-sided surface (ft^2) 40 G=3*A'2-sided thermal conductance (Btu/h-F) 50 TMIN=50+1470/G'min water temp (F) 60 TMAX=126'initial max temp (F) 70 C = 23400/(TMAX-TMIN)'thermal mass (Btu/F) 80 RC=C/G'time constant (hours) 90 TMAX=126+(TMIN-126)*EXP(-8/RC)'new max temp (F) 100 IF ABS(C-CL)>.1 THEN CL=C:GOTO 70'iterate 110 DEPTH=12*C/A/62.33'water depth (inches) 120 PRINT NTRAYS;C;RC;TMIN;TMAX;DEPTH 130 NEXT 1 485.2478 5.054664 65.3125 113.5336 2.919428 2 346.5029 1.804702 57.65625 125.1881 1.042344 3 330.3709 1.147121 55.10417 125.9337 0.6625439 4 324.2509 0.844403 53.82813 125.9945 0.4877029 We might use 2 trays with 346 total pounds of water. Nick