Experimental and numerical study on performance of hybrid refrigeration system that combines vapor compression and thermoelectric systems

Performance of hybrid vaccine freezer that combined thermoelectric coolers with vapor compression refrigeration: Experimental assessment

“…The cooling capacity inside different chambers is obtained according to the methods that are provided in the open literature, such as Vian and colleagues. 15,17,20 Once the developed system attains a steady state, the cooling capacity of the cold side of the heat exchanger is equal to the freezer's heat loss, as the following 20 : The following empirical correlation in terms of Nusselt number is employed to determine the convection heat transfer coefficients (hc) for the walls in terms of Nusselt number, as follows 26,27 :…”

“…26 This correlation has been successfully applied in the design of household refrigerators, as presented in Vian and colleagues. 15,17,20 It is considered for laminar flow and neglects the effects of viscosity dissipation in a planar plate. Therefore, the convection coefficients in terms of Nusselt number for the inside freezer compartment are obtained using the following correlation where it is suggested for a flat plate when the air velocity is low.…”

“…The amount of heat that can be transferred from the freezer compartment walls represents the cooling capacity. The cooling capacity inside different chambers is obtained according to the methods that are provided in the open literature, such as Vian and colleagues 15,17,20 . Once the developed system attains a steady state, the cooling capacity of the cold side of the heat exchanger is equal to the freezer's heat loss, as the following 20 : $$${Q}_{c}={Q}_{w}=U{A}_{\mathrm{wall}}({T}_{i}-{T}_{a}),$$$ $$$U=\frac{1}{\frac{1}{{{hc}}_{int{.$$…”

“…The Nusselt number is calculated using the correlation given by Parmelee 26 . This correlation has been successfully applied in the design of household refrigerators, as presented in Vian and colleagues 15,17,20 . It is considered for laminar flow and neglects the effects of viscosity dissipation in a planar plate.…”

“…They found that the COP of the TEC improved by about 20% when the speed of the fan was increased from 500 to 2000 rpm. Fu et al 20 experimented the performance of the hybrid domestic refrigerator (TEC and VCC) system with a freezer compartment volume of 0.018 m 3 . Their experiments showed that using an additional 99.5 W of electricity brought the freezer temperature down to −38.1°C.…”