Description
ABSTRACT
This paper describes the quick and precise control method for a portable domestic refrigerator. The propose controller is based on the fuzzy logic and neutral network designed maintaining the constant inner temperature (of the refrigerator and improving the refrigerator efficiency. The fuzzy logic controller is used to maintain the inner temperature inspite of the environment variation such as outer temperature change of the volume change of the stored food to the refrigerator a neutral network is used and rained to recognize the user pattern such as the number of the door opening of the refrigerator.
The first ordered approximated mode of the refrigerator is used for the simulation. Through the simulation in the case of the outer temperature change like summer or winter, the proposefuzzy logic controller with a neutral network is show to be more efficient than the conventional (on-off) controller.
TABLE OF CONTENTS
Tile Page i
Certification ii
Dedication iii
Acknowledgement iv
Abstract v
Table of Contents vi
CHAPTER ONE: INTRODUCTION
1.1 Refrigeration System 1
1.2 Aim and Objective 2
1.3 The Need of Refrigerator 3
CHAPTER TWO
2.1 Literature Review 5
2.2 The Air Refrigeration System 5
2.3 Vapour Absorption Refrigeration System 7
2.4 Principle of Operation Absorption Refrigeration System 7
2.5 The Vapour Compression Refrigerator System 8
2.6 Component Part of Refrigeration System 11
CHAPTER THREE:
DESIGN CALCULATION FOR REFRIGERATOR SYSTEM
3.1 Refrigerant Selection 12
3.2 Determination of the Flow Rate 13
3.3 Compressor 15
3.4 Compressor Discharge Temperature 16
3.5 Specific Volume-Compressor Discharge 17
3.6 Condenser 18
3.7 Evaporation 19
3.8 Insulator 19
3.9 Capillary Tube 20
3.10 Suction Line 21
3.11 Heat Balance for the System 21
3.12 Coefficient of Performance (C.O) 22
CHAPTER FOUR
DESCRIPTION OF COMPONENT PARTS AND WORKING PRINCIPLE
4.1 The Compressor 23
4.2 Condenser 25
4.3 Evaporator 29
4.4 Factor Affecting the Vapourization of a Liquid 30
4.5 Capillary Tube 31
4.5 Strainer Drier 32
4.7 Thermodynamic Analysis 33
4.8 Steps in Selecting Refrigerant 33
4.8.1 Classification of Refrigeration 33
4.8.2 Primary Refrigerant 34
4.8.3 Secondary Refrigerant 34
4.8.4 Desirable Properties of a Refrigerant 34
4.8.4.1 Thermodynamic Properties of a Refrigerant 35
4.8.4.2 Chemical Properties of a Refrigerant 35
4.8.4.3 Physical Properties of a Refrigerant 35
4.8.4.4 Other Properties of a Refrigerant 36
CHAPTER FIVE: CONCLUSION AND RECOMMENDATION
5.1 Conclusion 37
5.2 Recommendation 38
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 portable 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.
- 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.
As a result, we are not limited to the engagement of fruits vegetables and other product growth locally at any given time of the year, but we can have food product from the distance lands an4 other part of the country.
Economic Growth: refrigeration has helped the economy of many areas by providing a means preserving their product enrooted to remote area for consumers.
Hospital: Refrigerators are used in the hospitals for the preservation of bone, blood tissue and some drugs that are to be kept under a particular temperature. It is also pay and important roles in the act of keeping dead body in the mortuaries from being decayed.
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CHAPTER FIVE
CONCLUSION AND RECOMMENDATION
5.1 CONCLUSION
Refrigeration is the science of producing and maintaining a temperature below that of the surrounding atmosphere i.e it is an act of removing heat from a substance to be cooled.
This project work was a direct integration of both the theoretical acknowledge and practical skills required in the course of study, and has the acquainted the relevance of engineering science to technological growth and development.
The project was based on the result of through research, analysis calculation of the component parts.
However note that this project works is design for domestic purposes. Furthermore, it teach users of refrigerator thenecessary of taking good care of there refrigerator, the using sharp and pointed object in removing product from the evaporator cool. It is necessary to paint the final finished work piece in other to prevent the effect of corrosion or rusting and as well enhance or promote its aesthetic value.
5.2 RECOMMENDATIONS
As the project work is aimed at improving and broadening students knowledge, this expressed the relevance of transforming theoretical knowledge into useful practical reality.
Better zeal would be spurned if the school and students would note the following:
- Student should make it compulsory to participate in their project work
- All necessary facilities, tools and equipment should made available to facilitate the execution of the project by the student intime
