Friday, November 03, 2006

Wikipedia as an encyclopedia of technology

Background: At work one of the things I am responsible for is the cooling of the equipment in the computer room. We have a Liebert Foundation XDF cabinet, a cutting-edge design that uses a digital scroll compressor, a local R-407C refrigerant loop to provide cabinet cooling, with heat elimination via a plate condenser into a water-glycol loop that transfers the eliminated heat to a drycooler mounted on the roof. Now, I learned in high school chemistry about gas laws and catabatic expansion and the general principles by which refrigerators work. However, I have never had a reason to learn any practical knowledge of this, or even think very hard about the details of the technology. Our XDF unit has had some difficulties in the past weeks, which have finally been traced to a refrigerant leak and today finally repaired, permanently, we hope. In any case, I wanted to learn more about the technology we're using, and specifically about drycoolers, a technology that I freely admit that I don't really understand. So I tried to research them on the web. Sadly, Wikipedia has no article on drycoolers. None of the industrial refrigeration articles mention them, even though they're widely used in commercial and industrial refrigeration systems. In fact, neither "drycooler" nor "dry cooler" appears in any article on Wikipedia at all. (I still don't know exactly how one works. I suppose I should ask my sales engineer sometime.)

In general, Wikipedia's coverage of technical topics not related to computers, airplanes, or trains, is spotty. The other area where I've specifically noticed this is electrical distribution systems. One of my other responsibilities includes ensuring that the computers get enough power. We upgraded our UPS from a 12kVA single-phase unit to a 20kVA three-phase unit. At the time, I was not really clear on how three-phase works, and so I researched the topic. Wikipedia has ok, but not good, coverage of this topic. It has much poorer coverage of the power distribution grid and the technologies used to accomplish power distribution. The article on power conversion states that "power conversion is the process of converting power from one form to another" and then goes on to list several forms of power that one might convert between. It also lists a few methods used. It does not discuss the relative merits and disadvantages of each method, or talk about which ones are predominant. The discussion of why one might want to convert power is superficial and conclusary. No major vendors of power conversion products are listed. All of these things that I would expect in a decent technical encyclopedia article. The current article is woefully inadequate.

Surely there are some people out there with expertises in these areas who might do something about Wikipedia's poor coverage of commercial power systems and commercial refrigeration systems. I suppose the main reason there is not good coverage of these topics is that these are topics that tend not to be studied in colleges; they are skills normally learned initially in trade schools, and mastered eventually in on-the-job apprenticeships. And these people, I strongly suspect, are not on Wikipedia, and even if they are are more likely to write about professional wrestling, NASCAR racing, or football than they are about the secrets of their trade. Still, there are engineering students who must learn at least some of this stuff (someone has to design power converters and refrigeration systems, and those people generally have gone to college and garnered at least one degree in engineering). Is Wikipedia not appealing to engineering students? If not, why not?

2 comments:

  1. There is a passing mention at Cooling tower, but our coverage of HVAC is lacking. I'm no expert, but at least part of the problem may be terminology. These seem to be fan-cooled heat exchanges - like car radiators but for HVAC applications. I had not heard them called 'dry coolers,' but I understand the name, and there are several links to vendor sites. There is probably enough material for a section in 'HVAC', or 'Radiator.' I'm not sure what catabatic expansion refers to. Is it related to adiabatic expansion?

    You may be one a good track by asking "Why don't electricians contribute?" instead of "Why don't experts contribute?" I am an engineer, but to the area I know the most about I contribute almost nothing, mostly because of concerns about proprietary information. I do some work in other areas of engineering, but mostly I write about religion and politics.

    Is Wikipedia not appealing to engineers? Well, writing is not appealing to most engineers. Those who do like it might write about sports instead. Of course the sales engineer will 'contribute' links to Wikipedia.

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  2. Engineers are interested in designing machines. Not writing about them and then watching every kook on the internet drop by and make "improvements" to the article.

    But yes, Kelly, you make an accurate observation.

    A drycooler is basically like your car's cooling system, a fan and a heat exchanger that contains hot fluid.

    Other designs splash water on the radiator which then evaporates into the atmosphere, taking gobs of heat with it and providing a comfy home for Legionellosis. (actually the heat exchanger is usually submerged somewhere and the splashing elsewhere.)

    Since drycoolers don't use water evaporating into the atmosphere they have to work harder and be sized a larger to move the same amount of heat as a wet cooler. They use more energy but are simpler and therefore more reliable.

    If you have state of the art equipment for a high reliability application you shouldn't be putting up with frequent breakdowns. Go kick some ass.

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