Thermal Conductivity of Gases . tivity of Carbon Dioxide Near II . Thermal Conduc - the Critical Poine
نویسنده
چکیده
~~'he t hermal conductivity of CO 2 has been m.easured in a coaxia l cyl inder cell as a fu nctIO n of pressure over a range of t emperatures from 3.66 to 75.26 °C. P ar Licular attention was given to t he measurement s from 1 to 9 deg C above t he cri tical t emperature at pressures closely spaced to i nclude t he crit ical density. The t hermal co ndu ctivity of CO2(0) near t he cri tical point is ver y la rge compared to one a t mosphere \:a~ Lles around room t~mperature . At 1 deg C above t he cri t ical point t he t her mal cond uctl.vlty r ea?hes a maXUllum at t he critical density. This maximum is greater than t~e maxun a at hIgher t emperatures . At 75 .26 °C, 44 deg C above t be cri tical temperat ure ',h ttle unusual increase at t he crit ical densi ty was observed . ' Th e ratc of heat t r anspor t by convection in the cri t ical region is also very la rge. This problem was st ud wd carefull y in order t hat t he t emperature differences usee! were res t ri cted to t he region of laminar fl ow, and t ha t appropriate extrapolation p rocedures wcre u sed to find the ra te of heat t ransfer by t her mal conduction alone . ~~so, at d ensit ies and temperatures away f ro m t he cri tical region , new t hermal conductlVl t ? va lu es \I'ere obtained .
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