DETERMINATION OF THE CRITICAL PARAMETERS FOR NORMAL BUTANE BY VISUAL OBSERVATION OF PHASE-BOUNDARY DISAPPEARANCE AND CRITICAL OPALESCENCE
|
Accession number;07A0043224
|
| Title;DETERMINATION OF THE CRITICAL PARAMETERS FOR NORMAL BUTANE BY VISUAL OBSERVATION OF PHASE-BOUNDARY DISAPPEARANCE AND CRITICAL OPALESCENCE |
| Author;
()
YAMAMOTO KAZUYA
(Keio Univ., JPN)
YAMAMOTO SATOSHI
(Keio Univ., Graduate School, JPN)
|
Journal Title;Thermophys Prop
|
Journal Code:X0031A
|
ISSN:0911-1743
|
|
VOL.27th;NO.;PAGE.66-68(2006)
|
| Figure&Table&Reference;FIG.6, TBL.2, REF.4 |
| Pub. Country;Japan |
| Language;Japanese |
| Abstract;The critical parameters of normal butane were determined from the measurements by a newly developed visual observation method for the phase-boundary disappearance and critical opalescence. The new method can make quantitative judgment of the phase-boundary disappearance and critical opalescence by using a digital data processing for the image of red laser light. The red laser light can recognize the boundary more sensitive than the observation by naked eyes. The sample-gas filling process was also improved. The sample purity of normal butane is 99.99mol%. The saturation temperature and the saturation density were measured in a temperature range from 425.120K to 425.131K near the critical region. The critical temperature of 425.131K and density of 224.6kg m'-3' were determined based on our measurements. The critical pressure of 3786.2kPa was determined from a Wagner-type vapor-pressure equation, which can reproduce reliable experimental data within the experimental uncertainties from 200K to the critical point. The expanded uncertainties of the saturation-temperature measurements and the saturation-density measurements are 0.009K and 0.7kg m'-3', respectively. And the expanded uncertainties (k=2) of the critical temperature, critical density, and critical pressure are 0.012K, 1.9kg m'-3', and 0.8kPa, respectively. (author abst.) |
|
|
|
Related Articles;
|
|
