CHAPTER ONE
INTRODUCTION
1.1    REFRIGERATOR SYSTEM
Refrigeration is the process of removing heat from a substance and transfers it to another. It is also the science of production and maintaining a temperature below that of a surrounding atmosphere. That is, is the act of removing heat from a substance to be cooled Robet (2011).
In any refrigeration system, the maintenance of low temperature requires the continuous removal of heat from the product at low temperature and the discharge of heat at higher temperature.
The pressure surrounding a liquid affects the escape of the molecule. As the temperature increase the molecules acquires kinetic energy (velocity) and escape.
Refrigeration is accomplished through this method. Refrigeration therefore is that branch of engineering which deals with the principle of lowering the temperature of au insulated enclosure by extracting heat and rejecting to the surrounding with the aid of liquid refrigerant Robet (2011).
In chapter one, the report discussed the introduction to refrigeration system. Chapter two analyses the alternativeto refrigeration system, the description of component part and working principle is discussed in chapter three design calculation for a refrigeration system in chapter four, chapter five discussed and explain lip construction and assembly of the component parts. The conclusion
And recommendation is mention in chapter six.
1.2     AIM
This project work is aimed at designing a domestic refrigerator for food preservation.
OBJECTIVE
(1)     It also demonstrates practically how the various components of a refrigeration system function.
(2)     It is meant to educate and encourage students who may like to embark on similar project in future, using the available raw materials.
(3)    This project will help in the aspect of teaching refrigerator the necessity of taking good care of their refrigeration, the danger of using sharp and pointed object in removing product from the evaporator compartment. In this the section, the principle underlying in the different types of refrigeration system was employed in this project work.
The basic types of refrigeration system are:
(1)     Air refrigeration system.
(2)     Vapour absorption refrigeration system
(3)     Vapour compression refrigeration system.
The project design utilized the principle of vapour compression system being the most widely used cycle of refrigeration.
13 THE NEED FOR REFRIGERATOR
Stages of refrigeration review
House ho1d/Domestic Refrigerator: with the achievement or reliable in modem hermetic mechanical refrigeration system of small house - power size, emphasis is now placed on improving the appearance utility and convenience. Some micro —organisms such as bacteria, yeast and mold causes spoilage of food material such as meat, dairy products, eggs, fruits, vegetable etc. at normal temperature these organism become more active, causing decomposition of such food item at high rate depending on the condition and type of food product but if the temperature of these is greatly reduce the activities of these organism is also reduce if not completely render in active. This makes it possible to keep food for a long period of time. It is also use to reduce the temperature of water and soft drink for domestic consumption.
Commercial Purpose: not only is food preserve in our various home today, but commercial preservation of food is one of the most important application of refrigeration. Commercial preservation and transportation of food is also common that we be difficult to do without refrigerated food in America and Britain. The food that appears in the above named countries are produce. packaged, shipped, stored, and preserved by refrigeration.
Transportation: without the different types of modem refrigeration in store, warehouse, aircraft, railway, cars, stock and ships, the storage and the transportation of all types of perishable good would be impossible.