TY - JOUR
T1 - Thermal wave resonator cavity applied to the study of the thermal diffusivity of coffee infusions
AU - Tepepa, B. Briseño
AU - Marín, E.
AU - Martín-Martínez, E. San
AU - Orea, A. Cruz
PY - 2009/10
Y1 - 2009/10
N2 - Among the photothermal methods, the photopyroelectric technique, in its several experimental configurations, has been extensively used to measure the thermal properties of liquids, mainly the thermal effusivity and diffusivity. In this paper, the use of the so-called thermal wave resonator cavity method, in the cavity-length-scan mode, to measure the thermal diffusivity of commercial coffee infusions with samples at different concentrations and degrees of degradation induced by heating cycles is reported. A linear relationship between the logarithm of the pyroelectric signal amplitude and the sample thickness was observed, in agreement with the basic theory for the experimental configuration used here, from which the thermal diffusivity values of the samples were obtained. The thermal diffusivity was found to be almost independent of the coffee concentration in water but that this parameter is sensitive to sample modifications induced by degradation. This work represents another step to demonstrate the capability of the used method for characterization of the thermal properties of liquids.
AB - Among the photothermal methods, the photopyroelectric technique, in its several experimental configurations, has been extensively used to measure the thermal properties of liquids, mainly the thermal effusivity and diffusivity. In this paper, the use of the so-called thermal wave resonator cavity method, in the cavity-length-scan mode, to measure the thermal diffusivity of commercial coffee infusions with samples at different concentrations and degrees of degradation induced by heating cycles is reported. A linear relationship between the logarithm of the pyroelectric signal amplitude and the sample thickness was observed, in agreement with the basic theory for the experimental configuration used here, from which the thermal diffusivity values of the samples were obtained. The thermal diffusivity was found to be almost independent of the coffee concentration in water but that this parameter is sensitive to sample modifications induced by degradation. This work represents another step to demonstrate the capability of the used method for characterization of the thermal properties of liquids.
KW - Coffee infusions
KW - Photopyroelectric technique
KW - Thermal diffusivity
KW - Thermal wave
UR - http://www.scopus.com/inward/record.url?scp=70449527472&partnerID=8YFLogxK
U2 - 10.1007/s10765-009-0629-8
DO - 10.1007/s10765-009-0629-8
M3 - Artículo
SN - 0195-928X
VL - 30
SP - 1591
EP - 1597
JO - International Journal of Thermophysics
JF - International Journal of Thermophysics
IS - 5
ER -