Follow-up question:

Should I consider any of these Thermador slide-out models? First one is a slide-out chimney type, which could be a nifty idea to go between windows in our narrow galley kitchen. Thanks again.

https://www.ajmadison.com/cgi-bin/ajmadison/HDDB36WS.html

https://www.ajmadison.com/cgi-bin/ajmadison/HDDW36FS.html

https://www.ajmadison.com/cgi-bin/ajmadison/HMDW36WS.html

For really modest cooking, you probably can operate with any of your examples. On Hanukkah your open windows will air out the kitchen, but much grease will be deposited everywhere. If you truly want to keep it off the walls and ceiling, it is necessary to capture it immediately. This requires 400 - 600 CFM actual, or a 600 - 900 CFM blower rating. Make-up air will be required, except where not enforced, in which case windows may be opened. But this gets us into the combustion appliance safety conversation which you should have already read.

Capture (with reasonable volumetric flow rate -- CFM) requires that the hood overlap the pans sufficiently to intercept the expanding cooking plumes. One can argue for a hood overlap of 10 degrees from vertical relative to the larger pans that might be used, or choose to achieve a width 3-inches larger on each side (as in your 36-inch selection).

This also applies to the front-to-back dimension +/- various factors such as side skirts (usually commercial) and side cabinets, where the cooktop is mounted in the counter, and the cooktop hob configuration. For my Frigidaire, the actual depth of the active cooking zone (from front edge of front hob to the back edge of the cooktop) is about 18 inches. So the hood should protrude from the wall by an amount equal to the (a) cooktop-to-wall distance, plus (b) 18 inches, plus (c) 3 inches*. Ideally this should be the entry aperture and not include some large light bar. Hence, hoods in the 24- to 27-inch range should be suitable.

Best results for capture not only include overlap, but also some capture volume below the baffles to handle transient plume events. This leads to a hood style that is significantly different than your examples. Something more like this example from Wolf is in my view better.

Other comments related to your examples.

• The narrow chimney designs are intended for minimal visual effect and give up too much in performance for my taste.
• Slide out systems can reduce obtrusiveness, but most aren't baffle filtered, and even where mesh filters are appropriate (low flow rates), they tend to block a lot of the area one would want to have as open entry aperture.

Please note that my hood is a large Wolf Pro Island hood and I haven't used any of the examples you provide. My extrapolation of their performance is based on a general sense of fluid dynamics and reported plume behavior.

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*5 inches would better fit the 10-degree rule, but because for a wall configuration there is significant air flow into the hood front, there will be some slight bending of the plume shape that should allow a 3-inch from the pan overlap distance to be adequate. Note that the Wolf hoods have light bars in the front, so the aperture is more like 24 inches for a 27-inch front-to-back depth.

I should add in the interest of directly answering one of the questions: A narrow (height) chimney hood and a narrow (height) under-cabinet hood are equally marginal, so the choice between them, weighting for performance, would have to depend on details that are not usually obvious from pictures.

Ok thank you for all this info. I will look into an option more like what you suggest.

Do you hit your head on that 27” depth?!

My hood is set above my head at 34.5 inches from the cooktop. The factor that must be kept in mind is that one tends stand outside the plane of hood entry aperture and to bend to reach or look into pots, and this adds to the head-to-hood spacing. It is also possible to learn from experience to duck. If one wants a low hood and good sight line to the rear pots, then with a shorter hood the more greasy and odoriferous cooking should be done on rear hobs or burners. Hot plumes from front burners will miss capture if the hood doesn't overlap the plumes.

Commercial hoods are set 7 ft. from the floor or 48 inches above the cooktop. They also are required to provide at least 6 inches of overlap on each side. That is only 7 degrees, so generally flow rate and hood size are tailored for the circumstances, and side skirts are often used. A one-foot side skirt gets the sides down to 36 inches and good plume capture on the sides. Note also that these hoods are typically 4 ft front to back, so front burner capture is achieved.

Flow rates for these hoods are significantly higher. A residential application is under construction by opaone, and some images have appeared here recently.

Where money and space are not limitations, solutions such as is shown at the bottom of this web page are possible. http://www.handcraftedmetal.com/

Ha. Thank you again! Money AND space are concerns. I might go w this Zephyr to go over the induction range (even though it doesn’t quite meet your depth instruction), and then cook the latkes in cast iron skillet on our gas grill outside! I’ve been talking about trying that for years.

https://zephyronline.com/product/tempest-ii-wall/

Looks (from here) like a reasonable compromise.