Table 1. Examples of real-world power generation efficiencies.<\/p><\/div>\n
Fig 2. Examples of electricity generating plants.<\/p><\/div>\n
The UBC Paper<\/strong><\/p>\nCurzon & Ahlborn published their result in the American Journal of Physics in 1975. While it had previously been derived in 1957 by Ivan Ivanovich Novikov, in the journal Atomnaya Energiya, and independently in the same year by Paul Chambadal, in a book Les centrales nucl\u00e9aires<\/em>, these publication in Russian and French had little impact. Neither the UBC authors nor the editors and referees at the American Journal of Physics were aware of them. The publication of the result in an English-language journal brought the result to a much wider audience. To this day, this paper is still cited in the scientific literature about fifty times a year.<\/p>\nFig 3. Curzon and Ahlborn’s paper, initially rejected as “correct but of no interest”, still garnering ~50 citations a year, 45 years later.<\/p><\/div>\n
The Authors<\/strong><\/p>\nProfessors Curzon and Ahlborn joined the UBC Physics Department in the early 1960s. Frank Curzon came to Vancouver from the University of London, and Boye Ahlborn came from Ludwig-Maximilians-Universit\u00e4t Munch\u00ebn. At the time of their famous 1975 paper on thermodynamics, they were working together in the Plasma Physics group. This research work produced two successful Vancouver companies, Vortek Industries and TIR Systems.<\/p>\n
Fig.4. Boye Ahlborn c. 1975.<\/p><\/div>\n
Fig.5. Frank Curzon c.1975.<\/p><\/div>\n
Boye was later Director of the UBC’s Engineering Physics Program and was instrumental in setting up the Engineering Physics Project Laboratory in the Hennings Building. Frank’s teaching career at UBC eventually spanned a full half-century.<\/p>\n
Model of a Four-Stroke Heat Engine<\/strong><\/p>\nFig. 6. Otto cycle engine (Alice Lam, UBC Engineering Physics).<\/p><\/div>\n
There are many named thermodynamic cycles – Otto (four-stroke gasoline engines in vehicles), Rankine (steam generators in coal-fired and nuclear power stations), Brayton (gas-turbines in aviation) etc. – which all trace locii of slightly differing shapes around the PV diagram. In each case the work done per cycle is the area enclosed by the locus and the efficiency is the work done divided by the heat input by the hot reservoir. The Carnot cycle is just an idealized version that is useful to consider as a limiting case.<\/p>\n
<\/p>\n
<\/p>\n
Updated by CEW 2019-10-02<\/strong><\/p>\n","protected":false},"author":6,"featured_media":2283,"template":"","tags":[178,166,179,180],"date_post_made_public":"0000-00-00","post_authored_by":"","hook":"All undergraduate physics students are taught the Carnot cycle as an example of a thermodynamic engine. The Carnot cycle is optimized for efficiency but unfortunately yields zero power, and is therefore not very useful in reality. However, it's analysis is mathematically elegant. How can we modify the Carnot analysis for real engines which are optimized for power without sacrificing mathematical simplicity?","big_ideas":"\r\n \t- There is a trade-off between efficiency and power<\/li>\r\n \t
- The Carnot cycle is most useful when considered as a limiting case<\/li>\r\n<\/ul>","thumbnail_for_post":"","series":false,"number_in_series":"0","supporting_classroom_materials":false,"supporting_experiment":false,"related_articles":false,"related_experiments":false,"related_classroom_materials":false,"_links":{"self":[{"href":"https:\/\/c21.phas.ubc.ca\/wp-json\/wp\/v2\/article\/833"}],"collection":[{"href":"https:\/\/c21.phas.ubc.ca\/wp-json\/wp\/v2\/article"}],"about":[{"href":"https:\/\/c21.phas.ubc.ca\/wp-json\/wp\/v2\/types\/article"}],"author":[{"embeddable":true,"href":"https:\/\/c21.phas.ubc.ca\/wp-json\/wp\/v2\/users\/6"}],"version-history":[{"count":11,"href":"https:\/\/c21.phas.ubc.ca\/wp-json\/wp\/v2\/article\/833\/revisions"}],"predecessor-version":[{"id":2278,"href":"https:\/\/c21.phas.ubc.ca\/wp-json\/wp\/v2\/article\/833\/revisions\/2278"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/c21.phas.ubc.ca\/wp-json\/wp\/v2\/media\/2283"}],"wp:attachment":[{"href":"https:\/\/c21.phas.ubc.ca\/wp-json\/wp\/v2\/media?parent=833"}],"wp:term":[{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/c21.phas.ubc.ca\/wp-json\/wp\/v2\/tags?post=833"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}