ABSTRACT

Due to irregular power supply common in developing countries, as well as the growing high cost of hydrocarbon, the need arises for the development of a dual energy source oven that uses both electricity and gas for heating oven chambers. The oven was fabricated with the use of indigenous materials according to the conceptual design. The oven consist of a housing unit(frame), a thermometer, a gas regulator, a tray, an oven door, a perforated plate, a heating gas burner, an electric heating element, caster wheels/ rollers support. The housing unit which is the frame represents the entire outlook of the baking oven. The components make possible the use of alternative heat sources. In the heating chamber is an electric heating element that generates and dissipates heat within the enclosure. Cooking gas is supplied to the burner located in the lower chamber of the oven via pipe connection to the gas cylinder. Perforation allows for dissipation of unwanted gases within the chamber. COMSOL Multiphysics is used for simulation and for optimization of determined properties of raw state of unbaked cake flour, heating element. The performance test gave oven efficiency of 95.2 percent. The temperature of the entire system when considered in an ideal state as simulated by comsol performs better with gas as a heat source though slightly different from electric heater. For the temperature-varying density simulation, the temperature of the entire system and heating elements first decreases in temperature, then increases because density first rises with respect to time, then decreases with respect to time; therefore, the initial temperature drop of the system is due to the higher density, and the temperature rise is due to the decreasing density. The oven can be adapted for both domestic and industrial purposes and have been found very useful in bakery industries.

                                                       TABLE OF CONTENTS

Title Page                                                                                                                    i

Declaration                                                                                                                  ii

Dedication                                                                                                                  iii

Certification                                                                                                                iv

Acknowledgments                                                                                                      v

Table of Contents                                                                                                       vi

Abstract                                                                                                                     viii

CHAPTER 1: INTRODUCTION                                                                         1

1.0  Background of the study                                                                                     1

1.1 Statement of problems                                                                                         2

1.2 Objectives/ scope of study                                                                                   3

1.3 Justification                                                                                                          3

CHAPTER 2: LITERATURE REVIEW                                                                4

2.1 Overall concept                                                                                                    4

2.1.1 Local comparative analysis                                                                                5

2.1.2 Empirical model                                                                                                6

2.2 Principle of operation of the oven                                                                        7

2.3 Importance of baking ovens                                                                                8

2.4 Heat transfer and work done by the oven                                                                       8

2.5 Basic laws governing heat transfer                                                                      9

2.6 Modes of heat transfer                                                                                        10

2.7 Thermodynamic comsol analysis of the oven                                                    10

CHAPTER 3: MATERIAL AND METHODS                                                   11         

3.1 Design concept                                                                                                   11

3.2 Material selections                                                                                  11

3.2.1 Material quantity and cost                                                                               14

3.3 Design methodology                                                                                            15

3.4 Design analysis                                                                                                    15

3.5.0 Energy requirement of the gas oven                                                                 16

3.5.1 Heat of formation of Carbon IV Oxide;                                                                      17

3.5.2 Electric energy requirement of the oven                                                                          18

3.5.3 Heating element rating power of electric heating element                               18

3.6 Design concept of the oven                                                                                 19

3.6.1 The part view of the oven                                                                                 20

3.6.2 Autographic views of the oven              

 3.6.3 Section view showing the lagged parts of the oven                                        22                                

3.6.4 The major components of the oven                                                                  23

CHAPTER 4: RESULTS                                                                                       24

4.1. Machine testing                                                                                                   24

4.2. Operation of the oven                                                                                         24

4.3 Comsol result for oven                                                                                         24

CHAPTER 5: SUMMARY, CONCLUSION AND RECOMMENDATION   36

5.1 Conclusion                                                                                                           36

5.2 Recommendation                                                                                                 36

REFERENCES                                                                                                        37