APPLICATION OF PHASE CHANGE MATERIAL IN CONVECTIVE SOLAR UNIT DURING YOGURT MANUFACTURING
Loading...
Date
2023
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
ICAR-NDRI, KARNAL
Abstract
This study aims to select an appropriate phase change material (PCM) and
container material for the solar based yogurt fermentation unit. The study was
conducted in four phases. In the first phase, several PCMs were studied from
the literature, out of which three PCMs, i.e., Paraffin wax, Bees wax, and palm
oil, were selected. Melting characteristics of the chosen PCMs were studied to
determine their suitability for the intended application. The melting
temperatures of the investigated phase change materials (PCMs) were 59.3°C
for paraffin wax, 68.1°C for beeswax, and 43°C for palm oil. Melting time was
found lowest for palm oil (20 mins), followed by paraffin (35 mins) and beeswax
(48 mins). The second phase focused on enhancing the thermal conductivity of
the selected PCM. Metallic Inclusion was utilized to enhance the thermal
conductivity of PCM. The Experiment design and parameters optimization was
carried out by RSM using Design Expert. 13.3 % metallic inclusion was found
optimum for thermal conductivity enhancement. In the third phase, suitable
container material was selected by comparing the heating and cooling time for
different containers. PET was found ideal as it facilitates delayed heat release
during PCM discharging (240 mins) compared to SS 304 (150 mins). In the
fourth phase, the performance of the PCM integrated system was evaluated.
The integrated system successfully maintained the required yogurt incubation
temperatures for 10-11 hours. The prepared yogurt was analysed to assess its
quality and consistency in terms of texture, taste, and overall product attributes.
With the application of the PCM, the operational duration of the system was
extended by an additional 3 hours, resulting in a notable increase of
approximately 26.6%. It enabled the system to continue functioning even during
late evening hours in absence of sunlight.