Design And Construction Of A Refrigerating Unit
The design and construction of a high-performance refrigerating unit tailored for commercial applications necessitates meticulous consideration of various factors, including energy efficiency, cooling capacity, environmental sustainability, and operational reliability. Employing advanced thermodynamic principles, innovative materials, and cutting-edge technologies, this project aims to develop a refrigeration system that optimizes cooling efficiency while minimizing environmental impact. Through meticulous engineering and rigorous testing, the unit will be configured to meet the diverse needs of commercial enterprises, ensuring reliable temperature control for perishable goods while adhering to stringent energy efficiency standards. By integrating components such as efficient compressors, eco-friendly refrigerants, and intelligent control systems, the resulting refrigerating unit will offer a sustainable and cost-effective solution for diverse commercial settings, ranging from supermarkets to food processing facilities. Through continuous refinement and adaptation to evolving industry standards, this project aims to set a new benchmark for refrigeration technology, aligning with the growing demand for environmentally conscious and energy-efficient cooling solutions in the commercial sector.
The design and construction of s refrigerating unit is handled from the knowledge of the working principles of laws of thermodynamics.
The size of the containing vessel i.e the case as established to be of 45cm by 32 cm in dimension. The Angle iron mild steel to used in the fabrication and welding. The box case of two layers are fabricated. Plastic (cooler) box is then placed inside the upper part with the other parts of the refrigerator were brought in. they were all fixed onto a wooden base with all the connections (electrical) made.
The capacity of the refrigerator is based on the workdone by the compressor which is O.I hp in specification. The size of the components used are
i. Condenser: The size is 0.1hp and it is a plate type condenser with extended surface.
ii. Compressor: The size is 0.1hp (75 watts)
iii. Copper wire: it is of 0.5cm in diameter and the total copper wire length is about 600cm (1½ roll)
The introduction of cooling fluid and filling of the compressor enabled the compressor to start functioning when connected to electricity using a 13 AMP rated socket
The interior of the plastic box is lined with dominium box with tubes arranged in convolution around it. This world effectively and cooled the water dropped into it. It compares favorably with the ones in the market.
TITLE PAGE
LETTER OF TRANSMITTAL
APPROVAL/CERTIFICATION
DEDICATION
ACKNOWLEDGMENT
ABSTRACT
TABLE OF CONTENT
CHAPTER ONE
1.0 INTRODUCTION
1.1 SCOPE OF THE PROJECT
CHAPTER TWO
HISTORY OF REFRIGERATION
TYPES OF REFRIGERATING DEVICE
USES OF REFRIGERATION
CHAPTER THREE
SEQUENCE OF OPERATIONS
SELECTION OF REFRIGRANTS
CONSTRUCTION PROCEDURE
ECONOMIC ANALYSIS
CHAPTER FOUR
4.1 CONCLUSION
4.2 RECOMMENDATIONS
REFERENCES
INTRODUCTION
Refrigeration is the process of lowering the temperature of a substance below that of its surrounding.
Refrigeration is the practical application of the first and second law thermodynamics. Comprehensive understanding of the basic principles of thermodynamics is crucial for full understanding of basic operation of refrigerator. The first law states that the energy can neither be created nor destroyed. If energy of 2.5J appears in one forms it appears in another without a corresponding decrease of energy on the other form. The second law states that no system can receive heat at a given temperature and reject it at a higher temperature without receiving work from the surrounding heat always flow from Warner to cooler body. Through consideration of these laws, the ideal refrigeration cycle are considered. The carnot cycle is reversible and consist of adiabatic compression witherma rejection of heat, adiabatic expansion and wothermal addition of heatl the carnot cycle is unattainable ideal which serves as a standard of comparison and it provides a convenient guide to the temperature that should be maintained to achieved effectiveness. The efficiency or coefficient of performance (C.O.P.) of a carnot cycle depends on the temperature at which heat is added and rejected.
Therefore,
C.O.P = T1
T2 – T1
Where T1 = Evaporation temperature
T2 = Conducting temperature
In actual refrigeration there will be issues causing C.O.P to be less than that for ideal cycle. The basic methods of refrigeration like the mechanical refrigeration ejector (steam jet) refrigeration absorption refrigeration uses similar process for obtaining refrigeration effect. That is evaporation in the evaporator, condensation in the condenser, the main difference is in the way used refrigeration being done. The most compression. The cycle efficiency can be ignored in a number of ways.
1. Multistage system: When evaporation and condensing temperature (pressure) difference is large, it is prudent to separate compression into two stages. The use of multistage system open up the opportunity to use flash gas removal and inter cooling as a measure to improve performance of the system
2. Cascade system: This appears in situation where the evaporating temperature is very low (below 600c). the refrigerant is used to achieve the cooling. The liquid with low boiling points are used as refrigerants.
1.1 SCOPE OFD THE PROJECT
The scope of this project is mainly concerned with the design and construction of a refrigerating unit that has a very performance level and with the cost of fabrication lower than that of existing prototype
A good refrigerator is one that has all the basic components of compressor, condensers, fan motor, copper tubes and other. This project must apply all the principles of refrigeration.
Design And Construction Of A Refrigerating Unit:
Designing and constructing a refrigerating unit requires careful planning and consideration of various factors, including the type of refrigerant, the intended application, cooling capacity, energy efficiency, and safety standards. Below is a general outline of the steps involved in designing and constructing a refrigerating unit.
1. Define the Requirements:
Determine the cooling capacity required (in BTUs or watts) based on the application (e.g., household refrigerator, industrial freezer, air conditioning).
Establish the temperature range needed for cooling or freezing.
2. Select Refrigerant:
Choose a refrigerant that meets environmental regulations and safety standards. Common refrigerants include R-134a, R-410a, or natural refrigerants like ammonia or carbon dioxide.
3. Components Selection:
Select key components, including:
Compressor: Responsible for compressing the refrigerant gas.
Condenser: Removes heat from the refrigerant.
Evaporator: Absorbs heat from the surroundings to provide cooling.
Expansion valve: Regulates refrigerant flow and pressure.
Piping and tubing: Connects the components and carries refrigerant.
Heat exchangers: Improve efficiency.
4. Design the System:
Create a schematic diagram of the refrigeration cycle.
Calculate the required sizes and capacities of components.
Determine the layout of the unit, considering space constraints.
5. Energy Efficiency:
Incorporate energy-efficient features like variable-speed compressors, insulation, and heat recovery systems to reduce energy consumption.
6. Safety Considerations:
Follow safety standards and regulations for refrigeration systems.
Implement safety measures such as pressure relief valves, alarms, and emergency shut-off systems.
7. Build the Unit:
Assemble and install the selected components according to the design.
Weld or connect piping and tubing with care to prevent leaks.
Ensure proper insulation to minimize heat exchange with the surroundings.
8. Testing and Commissioning:
Conduct leak testing to ensure the system is airtight.
Charge the system with the appropriate amount of refrigerant.
Test the unit’s performance, including temperature control and energy efficiency.
9. Maintenance and Service:
Develop a maintenance schedule to keep the refrigerating unit in optimal condition.
Train personnel in proper operation and maintenance procedures.
10. Compliance and Documentation:
Ensure that the unit complies with all relevant codes and regulations.
Maintain detailed records of design, construction, and maintenance activities.
11. Environmental Considerations:
Implement proper refrigerant management, including recovery and recycling.
Dispose of old or unused refrigerants according to environmental guidelines.
Remember that designing and constructing a refrigerating unit can be complex, and it may require specialized knowledge and skills. It’s crucial to consult with experienced engineers and follow industry standards and safety protocols throughout the process. Additionally, local regulations and building codes may vary, so it’s essential to comply with all applicable requirements in your area.