01-01-2013, 01:53 PM
DESIGN AND ANALYSIS OF SOLAR THERMOELECTRIC REFRIGERATION SYSTEM
INTRODUCTION
1.1. SOLAR THERMOELECTRIC REFRIGERATION
Use of refrigerator to keep food fresh has become one part of daily life for
people living in current society. However, cannot enjoy the convenience offered by
refrigeration when we are in outdoor activities, such as geologic prospecting,
archaeological studying and scenic spot outing. Solar refrigeration is thought of as
one of the best techniques to address this issue due to its good match to the variation
of solar radiation, namely, the supply of sunshine and the cooling output of solar
refrigeration system reach maximum levels at the same season.
Solar refrigeration may be accomplished by using one of the following refrigeration
systems vapor compression, Absorption or thermoelectric refrigeration systems. The
first two systems need high and low pressure sides of a working fluid to complete the
refrigeration cycle, and are somewhat difficult to be developed into a portable and
lightweight solar device used outside.
The thermoelectric refrigeration system, which has the merits of being small,
lightweight, reliable, noiseless, portable and low cost in mass production, uses
electrons rather than refrigerant as a heat carrier, and is feasible for outdoor purpose
in cooperation with solar cells, in spite of the fact that its Coefficient Performance is
not as high as for a vapour compression Cycle.
Thermoelectric cooling, also called "Peltier Effect", is a solid-state method of heat
transfer through dissimilar semiconductor materials. It is based on the thermoelectric
effect known as ‘Peltier Effect‘ according to which if current is passed through a
thermocouple, then the heat is absorbed at one junction of the thermocouple and
liberated at the other junction. So by using the cold junction of the thermocouple as
the evaporator, a heat sink as the condenser and a DC power source as the
compressor of the refrigerator, cooling effect can be provided.
[Tool tech - Coimbatore] Ct ; 9543314213,9842968225.
1.2. OBJECTIVE OF PROJECT
The overall aim of the work is to design a domestic refrigeration system,
without moving parts, whose cooling system is based on thermoelectric technology.
In order to achieve this over all aim the following specific objectives has been put forward
Numerical simulation of the entire thermoelectric domestic refrigeration
system.
Design and construction of the thermoelectric domestic refrigeration
system
Performance analysis on the Refrigeration system under No Load and
Loaded conditions.
SCOPE OF PROJECT
The project involves the development of a suitable cooling module designed with
a fan to cool the Refrigeration system. This Refrigeration system needed to be
powered up by a DC power supply using a suitable Solar PV Cell.
The project scope involves the following elements
Sizing and Designing of the cooling system
Selection of the TECs
Selection of Fans and Heat sinks
DC power supply design
Assembly and Fabrication.
Temperature measurements for testing.
Power supply testing and troubleshooting.
[Tool tech - Coimbatore] Ct ; 9543314213,9842968225.
PRINCIPLES AND STRUCTURE
CONFIGURATION OF SOLAR THERMOELECTRIC REFRIGERATOR
Construction of a solar cell driven, thermoelectric refrigeration system, which is
mainly configured by the array of solar cells, controller, storage battery, rectifier and
thermoelectric cooling module, is shown in Figure. 2.1. In daytime, solar cells receive
solar energy and turn it into electric power supplied to the system by means of
photovoltaic effect. If the amount of electric power production is large enough, the
power surplus can be accumulated in storage battery besides driving the refrigeration
system. If the solar cells cannot produce enough electric power, for example, in
cloudy or rainy days, the storage battery may offer a makeup. The controller, also an
auto-switcher, plays a role to maintain the energy conversion process in most
optimized way. In nighttime, the storage battery, as well as a backup rectifier is used
to power the system. The cold side of the module is set inside the refrigeration
system and the hot side is set outside. A fin-type heat exchanger is tied with the hot
side in order to release heat more efficiently.