Temperature data was analyzed by means of the heat balance
and the convective heat transfer to obtain an evolution of the
overall heat transfer coefficients (U) with time (t) in Figs. 3e5. The
combination of errors of the temperature sensors and the fluid flow
meters readings were expected. A total measurement error
affecting the overall heat transfer coefficient was not greater than
6% for all the experimental runs. For all conditions except the high
flows (4 and 6 LPM) at the heating condition from 70 C to 74.5 C,
two phases of fouling phenomena were observed during the
experiments for 6 h. Firstly, a fouling period occurred in which the
overall heat transfer coefficient decreased rapidly with time.
The fouling period lasting approximately 2 h was then followed by
a post-fouling period, where the overall heat transfer coefficient
decreased relatively slowly. The results did not show the first phase
of fouling-an induction period. This is considered the first
uniqueness of coconut milk fouling since an initial induction period
(up to 1 h) was reported previously by Fryer [11] and Delplace,
Leuliet & Tissier [29] for dairy milk fouling. However, there may be
a very short period (a few seconds) after startup where the
induction period occurred, but was not observed due to the limited
efficiency of the measurement system
Temperature data was analyzed by means of the heat balance
and the convective heat transfer to obtain an evolution of the
overall heat transfer coefficients (U) with time (t) in Figs. 3e5. The
combination of errors of the temperature sensors and the fluid flow
meters readings were expected. A total measurement error
affecting the overall heat transfer coefficient was not greater than
6% for all the experimental runs. For all conditions except the high
flows (4 and 6 LPM) at the heating condition from 70 C to 74.5 C,
two phases of fouling phenomena were observed during the
experiments for 6 h. Firstly, a fouling period occurred in which the
overall heat transfer coefficient decreased rapidly with time.
The fouling period lasting approximately 2 h was then followed by
a post-fouling period, where the overall heat transfer coefficient
decreased relatively slowly. The results did not show the first phase
of fouling-an induction period. This is considered the first
uniqueness of coconut milk fouling since an initial induction period
(up to 1 h) was reported previously by Fryer [11] and Delplace,
Leuliet & Tissier [29] for dairy milk fouling. However, there may be
a very short period (a few seconds) after startup where the
induction period occurred, but was not observed due to the limited
efficiency of the measurement system
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