Talk:Windcatcher

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Contents

[edit] Merger

I looked at both articles and I disagree. Although both serve the same purpose, they seem to be distinct architectural touches. Lord Bodak 20:42, 8 May 2006 (UTC)

My vote is same as Lord Bodak. The article for the Arab version even says that their version is distinct and different. No merge.--Zereshk 22:51, 8 May 2006 (UTC)
Agreed, and sorry for hasty mergejumping. The Problem is, though, that the windcatcher is also referred to as a wind tower in a bunch of sources. Perhaps some sort of disambiguation is in order? Marm(t) 08:04, 9 May 2006 (UTC)
That can be a solution. Nevertheless they are not totally unrelated. I dont know how to sort that.--Zereshk 14:40, 9 May 2006 (UTC)

The term "windcatcher" for the "other" type of wind tower is completely made-up. E.g. in the UAE, where this (here so-called "Iranian") type of wind tower is common, they are only called "wind tower", almost never "wind catcher". (Simply compare [1] with [2].) Although the architectural styles may be different, they function the same way, they bear the very same name in English, and probably even in Arabic (both articles say "Badg(h)ir"). I strongly favour merging them into one single article and within this article you may distinguish between the Bahrain style and the "Iranian" style (btw. I doubt that "Iranian" fits here - they can be found all around the Gulf). Hence I re-added the merge tag. -- H005 14:57, 22 May 2006 (UTC)

For one thing, "Badghir" is not an originally Arabic word. The Bahraini article is wrong about that.--Zereshk 19:46, 22 May 2006 (UTC)
Maybe, I have not much of a clue about Arabic; what's the correct word then? Are there different terms for the "Bahrain" and "Iran" style towers? -- H005 21:51, 22 May 2006 (UTC)
Badgir is correct. But it's not Arabic, as the bahraini article claims.
I have no issues with a merging though. But they must be properly separated.--Zereshk 23:47, 22 May 2006 (UTC)
According to the Dictionary of Islamic Architecture is Mulqaf the Arabic term for wind-catcher. JdH 19:46, 1 July 2006 (UTC)

Unless anyone objects, I will merge the contents of Wind tower into this article. We can work out a suitable name any time. Tom Harrison Talk 20:17, 20 July 2006 (UTC)

I have merged Wind tower in here. Some cleanup is probably in order. Tom Harrison Talk 20:32, 14 October 2006 (UTC)

[edit] How does this work?

Very interesting! But I was wondering: How does this work?
The only thing I can think of that the breezes are bringing in cool air from nearby mountains, and that the windcatcher is high enough to catch that cool air. So it would only work when the local meteological conditions are just right; in the lowlands it would not work. JdH 16:26, 1 July 2006 (UTC)

I thought the article was clear on how it works. The second paragraph is quite detailed. If you stand next to the base of a windcatcher inside the house, such as the tall one in Yazd (Dowlat Abad) , youll feel the air moving from the room into the column, not the other way around. That is, the windcatcher doesnt "catch" the air from the outside as its name implies. It uses the outside air to suck out rising hot air from the column.--Zereshk 03:50, 3 July 2006 (UTC)
Stack effect. But it does not explain where the cool air comes from that has to be sucked in to replace the warm air that moves up the chimney. On a hot summer day all you would do is replace hot inside air with hot outside air. Unless you precool the air that is sucked in, e.g. through underground ducts or some other means of natural air conditioning it is not going to do much good.
Those water reservoirs that are mentioned in the next paragraph make more sense: evaporation of water provides a natural means of air conditioning; all you need to do is vent warm humid air to the outside and replace it with dry outside air. JdH 09:21, 3 July 2006 (UTC)
I urge you to someday visit kashan to seek your answers. Several theories can be thought of regarding your question. But I can tell you these for certain:
  1. The cooler air doesnt come from the outside. It seems to be a product of the interior. Keep in mind that during the evening, temperatures in Iranian deserts do get chilly, even in summer. Traditional house designs made full use of that.
  2. Many Shabestans dont have any windcatchers. And yet one experiences the chilled temperatures in them, even in the midst of summer. My theory is that these structures were made out of excellent heat resistive materials. Why do caves feel so cold and chilly, even if the outside air is blistering? Same here. Even in my prents house in Arkansas, the basement was always much cooler than the above floors whether airconditiong was working or not.
  3. During to my visit to Kashan's many traditional houses (Tabatabaei, Borujerdi, Abbasian, Amerian), I noticed Qanats passing by underneath the houses at one point or another.
  4. I dont recall seeing any such devices (widcatchers, shabestan, etc) in the Mazandaran and Gilan provinces. There, the weather is highly humid with much rain.
I suspect that:
  • excessive shading in the traditional house designs in Persia (notice the incredibly narrow Kuchehs and tall walls minimizing direct sunlight
  • Highly non-symmetric design of the neighborhood (which blocks desert hot winds in summer and retains the warmth in winter)
  • convective ventilation using windcatchers
  • use of multiple overlapping layers and elements in the design of the house (In the Borujerdi-ha House, the floors of the House sectionally overlap: The Talar is open to the second floor and first floor, and part of the top of the basement as if to maximize air circulation)
  • Use of thick slabs and walls (acting as excellent heat resistors),
  • Use of Qanats passing thru the house
  • natural dry aired climate
  • the central howz of the house
  • Use of devices like Panjdari, which are open during the evenings and nights allowing in cool desert air, and closed during the day to block out the sunlight and hot air (windows were not made of metal and all used colored glass).
...all contribute and may answer the question of where the cool air comes from.--Zereshk 09:57, 3 July 2006 (UTC)


I have heard elsewhere that evaporation (from the quanats, I guess) is the key. Maybe my source was wrong, but I was surprised to see so little mention of evaporation as a part of the system here. Dvd Avins 13:50, 3 July 2006 (UTC)
Youre right about that.--Zereshk 04:36, 4 July 2006 (UTC)
The way I understand the stack effect is that it works by difference in temperature: When the temperature inside is higher than outside temperature the warm inside air will flow up the windcatcher, and at the same time cooler outside air is drawn in at the lower level. But the reverse is also true: When the temperature is higher outside than inside cool inside air will leave the building through open windows or cracks, and warm air will enter through the top. So I suspect that human intervention is an important factor too: During the night people will open windows or Panjdari or whatever to let cool air enter the building, but close those during the daytime to keep the cool air in.
The reason I was asking those questions is that I was wondering: what is wrong with the typical American suburban home that causes the cost of air conditioning to be so sky high? The answer as I understand it from your interesting explanation above is that Americans ignore most (if not all) common sense approaches that are used in traditional architecture. JdH 13:39, 3 July 2006 (UTC)
Indeed. The apartment I live in here in Texas doesnt even have any convective devices (not even an air fan or something in the bathrooms!) and the air conditioner is almost running 24/7 (unless we get some rian or something). I was surprised at the many simple Physics principles that ancient and traditional Iranians used in their desert architecture (excellent heat resistance, lighting properties, etc.). And yet they do and did seem to have a drawback of not being tremor-protective in their structure and designs. My advisor once mentioned this weakness of Persian desert architecture, pointing to the bulkiness and earthquake proneness of the thick adobe walls and brick material. But then again, Iranians see things like earthquakes from a fatalism point of view. You can still see this view when you look at modern Tehran: they are building as if there is no danger or potential hazard, stacking buildings right on top of eachother with the most minimum of safeguards. All this while warnings of a major overdue tremor are constantly repeated in the media. Unfortunately, traditional Persian architecture is being driven to extinction by modern development and mass housing projects. What a shame.--Zereshk 04:36, 4 July 2006 (UTC)

[edit] Description

There is no description of the specific design or physical structure of a windcatcher. 128.42.160.92 08:16, 26 September 2006 (UTC)

Venturi effect?
From the description is does not become clear whether or not the Windcatcher is equipped with a cap to create a Venturi effect to create an updraft whenever there is a breeze. The phrase "....whenever a breeze or wind passes through the tip of the windcatcher..." suggests something like that, but no details are provided about the design of the tip of the windcatcher. See The Log Rack or Cap That Chimney for how such a cap may look like. JdH 11:33, 20 October 2006 (UTC)

This thing needs some sources.

[edit] Ports

Article states this:

"First, a windcatcher is capped and has several directional ports at the top (Traditionally four). By closing all but the one facing away from the incoming wind, air is drawn upwards using the Coanda effect"

However the diagram shows two open ports. The downward draught shown in the diagram is also problematic - surely it illustrates hot air is being sucked in and down - that can't be right? I find the article badly describes the physics of the process. I'm not even sure if the Coanad effect is relevant - sounds more like a venturi effect. Additionally the discussion of cracks in the building is unclear. The cooling of the water in the qanat by the night air and then cooled further still by evaporation, combined with the stack effect does make sense. Also how are the wind ports operated - shutters on a string and by whom? —Preceding unsigned comment added by 124.191.112.44 (talk) 23:02, 10 March 2008 (UTC)

[edit] Merger

as the history shows not many years ago bahrain was a part of Iran so definetly the "Badgir" that arab world wants it as an arabic achitcting is iranian origin.and in the other arabs wants everything for themselves like: persian gulf.........so I think in the future theyll say"we were the first people who built pyramids of egypt" but they as a wild group of people in the history had nothing.[1] —Preceding unsigned comment added by 85.15.38.64 (talk) 17:52, 27 March 2008 (UTC) Aida Afsari.anyone that has any argument Ill be waiting at cute_britney_2007@yahoo.com