tag:blogger.com,1999:blog-3462870758832574326.post3299822717076462988..comments2024-03-26T03:48:57.771-04:00Comments on Makeatronics: Sous Vide Part 1: What and Why?Nich Fugalhttp://www.blogger.com/profile/01260987815174387425noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-3462870758832574326.post-1790018504376222912013-08-20T20:53:38.974-04:002013-08-20T20:53:38.974-04:00I've never cooked two turkeys at once, so I do...I've never cooked two turkeys at once, so I don't have any direct knowledge of what you're saying. But here's my thoughts:<br /><br />I doubt that the cooler thermal mass of the extra turkey is cooling the oven by any appreciable amount. More likely the heat transfer through the walls/door of the oven is the primary driver of the heating cycle. So the on/off time of the element shouldn't change much with one vs. two turkeys.<br /><br />When cooking two turkeys, do you put them side by side, or one over the other? If the latter, and you cook them uncovered, then each turkey is exposed to half the radiation (assuming you alternate positions) since the lower is shadowed by the upper. That may be the radiation comment your colleague was getting at. However, if you cook them covered then the radiation induced cooking is greatly reduced, though there could be a slightly higher temperature inside the cooking vessel if it's not entirely ventilated.<br /><br />As for the heating/cooling cycles they definitely are exponential. They look linear on the graph only because their duration is short in comparison to the exponential time constant, and can be satisfactorily modeled as linear because of this. You'll notice that once the oven was shut off it is very obviously exponential. I didn't mention in the post, but I also opened the door when the oven shut off which shortened the time constant significantly.Nich Fugalhttps://www.blogger.com/profile/01260987815174387425noreply@blogger.comtag:blogger.com,1999:blog-3462870758832574326.post-89467155364217094902013-08-20T18:50:54.015-04:002013-08-20T18:50:54.015-04:00I found myself on your blog trying to figure out t...I found myself on your blog trying to figure out the following question: "Why does it take longer to oven-cook two turkeys than just one?"<br /><br />In both cases the surface area to volume ratio is the same, so the only thing that will lengthen the cooking time is a lower average temperature.<br /><br />In a heat/cool cycle with two turkeys, the heating leg will be twice as long and the cooling leg will be half as long, but if both the heating and cooling legs are linear, there's no way this affects the average. My initial idea was based on an understanding that the cooling should be exponential, though after seeing this post that's clearly not the case.<br /><br />My colleague suggested that maybe radiation from the heating elements had something to do with the cook rate, but given the two-turkey case has a higher on:off ratio, this suggestion lends to the two turkeys cooking faster, not slower.<br /><br />I'd really love to test this myself, but don't have the equipment to do it. Does two turkeys somehow lower the average temperature? I don't suppose you're curious enough to cook 3 turkeys?<br />Roberthttps://www.blogger.com/profile/01502728988678153263noreply@blogger.com