encompasses both mechanics and thermodynamics without the need for statistical
(subjective or informational) probabilities.”
Cuadras et al. (2015) proposed a method to characterize electrical resistor damage
based on entropy measurements. They postulated that irreversible entropy and the
rate at which it is generated are more convenient parameters than resistance for
describing damage because they are essentially positive in virtue of the second law
of thermodynamics, whereas resistance may increase or decrease depending on the
degradation mechanism. They tested commercial resistors in order to characterize
the damage induced by power surges. Resistors were biased with constant and
pulsed voltage signals, leading to power dissipation in the range of 4–8 W, which
is well above the 0.25 W nominal power to initiate failure. Entropy was inferred
from the added power and temperature evolution. They studied the relationship
among resistance, entropy, and damage. They stated that power surge dissipates
into heat (Joule effect) and damages the resistor. They observed that there is a
correlation between entropy generation rate and resistor failure. Cuadras et al.
(2015) concluded that damage could be conveniently assessed from irreversible
entropy generation.
Cuadras (2016) proposed a method to monitor the aging and damage of capacitors
based on their irreversible entropy generation rate (Fig. 4.3). Authors overstressed
several electrolytic capacitors in the range of 33 mFe–100 mF and monitored their
entropy generation rate. They observed a strong relationship between capacitor
degradation and entropy generation rate. Therefore, they proposed a threshold
entropy generation rate as an indicator of capacitor time-to-failure. This magnitude
is related to both capacitor parameters and to a damage indicator such as entropy.
They validated the model as a function of capacitance, geometry, and rated voltage.
Moreover, they identified different failure modes, such as heating, electrolyte
dry-up, and gasification from the dependence of entropy generation rate with
temperature.
Cuadras et al. (2017) proposed a method to assess the degradation and aging of
light emitting diodes (LEDs) based on irreversible entropy generation rate. Authors
Fig. 4.3 Capacitor entropy
generation rate versus time
(seconds) for different
voltage levels, After
Cuadras (2016)
4.1 Literature Review of Use of Thermodynamics in Continuum Mechanics
131
(subjective or informational) probabilities.”
Cuadras et al. (2015) proposed a method to characterize electrical resistor damage
based on entropy measurements. They postulated that irreversible entropy and the
rate at which it is generated are more convenient parameters than resistance for
describing damage because they are essentially positive in virtue of the second law
of thermodynamics, whereas resistance may increase or decrease depending on the
degradation mechanism. They tested commercial resistors in order to characterize
the damage induced by power surges. Resistors were biased with constant and
pulsed voltage signals, leading to power dissipation in the range of 4–8 W, which
is well above the 0.25 W nominal power to initiate failure. Entropy was inferred
from the added power and temperature evolution. They studied the relationship
among resistance, entropy, and damage. They stated that power surge dissipates
into heat (Joule effect) and damages the resistor. They observed that there is a
correlation between entropy generation rate and resistor failure. Cuadras et al.
(2015) concluded that damage could be conveniently assessed from irreversible
entropy generation.
Cuadras (2016) proposed a method to monitor the aging and damage of capacitors
based on their irreversible entropy generation rate (Fig. 4.3). Authors overstressed
several electrolytic capacitors in the range of 33 mFe–100 mF and monitored their
entropy generation rate. They observed a strong relationship between capacitor
degradation and entropy generation rate. Therefore, they proposed a threshold
entropy generation rate as an indicator of capacitor time-to-failure. This magnitude
is related to both capacitor parameters and to a damage indicator such as entropy.
They validated the model as a function of capacitance, geometry, and rated voltage.
Moreover, they identified different failure modes, such as heating, electrolyte
dry-up, and gasification from the dependence of entropy generation rate with
temperature.
Cuadras et al. (2017) proposed a method to assess the degradation and aging of
light emitting diodes (LEDs) based on irreversible entropy generation rate. Authors
Fig. 4.3 Capacitor entropy
generation rate versus time
(seconds) for different
voltage levels, After
Cuadras (2016)
4.1 Literature Review of Use of Thermodynamics in Continuum Mechanics
131