Government Engineering CollegeAurangabad

PRESENTED BY

ANSARI ABDUL BARI

BE10F02F006

ADIL FAQI MOMIN

BE10F02F033

PATHAN TAUFIQ [BE09F02F056]

Guided By

Prof M G RathiProject guideDepartment of Mechanical engineering 

A PROJECT PRESENTATION ONPORATABLE AIR CONDITIONER CUM

REFRIGERATOR

INTRODUCTION

• Refrigeration may be defined as the process of achieving and maintaining a temperature below that of the surroundings, the aim being to cool some product or space to the required temperature.

• Refrigeration systems are also used extensively for providing thermal comfort to human beings by means of air

conditioning.

NECESSITY

• Because of their easy maneuverability, relatively small size, and portability, portable ACs are ideal for a variety of settings, including apartments, rooms, workplaces, computer server rooms, or anywhere else where installing a traditional AC may not be feasible.

OBJECTIVE

• When we need to efficiently cool a small space such as a bedroom or office, a portable air conditioner is a great choice because it can solve the cooling challenge by lowering the temperature in a given environment. 

Here is a general overview of how a portable air conditioner works and its benefits. 

CARNOT CYCLE• Carnot refrigeration cycle is a completely

reversible cycle, hence is used as a model of perfection for a refrigeration cycle operating between a constant temperature heat source and sink.

• Process 1-2: Reversible, adiabatic compression in a compressor

• Process 2-3: Reversible, isothermal heat rejection in a compressor

• Process 3-4: Reversible, adiabatic expansion in a turbine

• Process 4-1: Reversible, isothermal heat absorption in a turbine

Limitations of Carnot cycle: • Carnot cycle is an idealization and it suffers from

several practical limitations. One of the main difficulties with Carnot cycle employing a gas is the difficulty of achieving isothermal heat transfer during processes 2-3 and 4-1. For a gas to have heat transfer isothermally, it is essential to carry out work transfer from or to the system when heat is transferred to the system (process 4-1) or from the system (process 2-3). This is difficult to achieve in practice. In addition, the volumetric refrigeration capacity of the Carnot system is very small leading to large compressor displacement, which gives rise to large frictional effects. All actual processes are irreversible, hence completely reversible cycles are idealizations only.

Simple Vapor-compression cycle

• The vapor-compression cycle is used in most household refrigerators as well as in many large commercial and industrial refrigeration systems and air conditioning system.

SYSTEM DEVELOPMENT

• An air conditioning cum refrigeration system consists of single compressor, single condenser, a refrigerating evaporator and an air conditioning evaporator.

• This unit is useful in both household as well as automobiles.

Specifications• Hermetic Compressor – 90 liters capacity

 • Condenser Air cooled

• Cooling coils Fin type evaporator

 • Expansion valve Capillary diameter 1 mm ,Length 2m

 • Fan and Blower 60 watt, 0.35 A/1300 RPM

 • Refrigerant (R134a) 500 gm.

 • Thermostat made by whirlpool

• Copper tubes Diameter : 2.5 mm

 • Height: 92 cm

Multi-evaporator system with single compressor

SELECTION OF EQUIPMENT

• Hermetic Compressors• Condensers - Air-cool condensers• Cooling Coils (Evaporator)• Expansion valve: Capillary tube • Fan and Blower: (60 watt, 0.35 A/1300 RPM)• Refrigerant: R-134a• ThermostatDrier and filter• Thermal Insulation

Portable AC cum Refrigerator

PERFORMANCE ANALYSIS

• Temprature Of an air conditioning evaporator:20oC • Temperature of refrigerating evaporator : -7oC • Capacity of refrigeration : 0.5 ton• Time to attain 0oC for freezer : 30 min• Time to attain -7oC for freezer :60 min• Time to cool (10*10 )room upto +22oC 70 min

• Temperature in condenser (T3) : 44ºc

APPLICATIONS OF PORTABLE AC CUM REFRIGERATOR

• Refrigeration deals with cooling of bodies or fluids to temperatures lower than those of surroundings

•1. Food processing, preservation and distribution

•2. Chemical and process industries

•3. Special Applications

•4. Comfort air conditioning

ADVANTAGES

• One of the main benefits of a portable air conditioner cum refrigerator is the fact that it can be moved from room to room Portability- It includes rolling casters. 

• Therefore, you can provide cooling comfort to any area with ease. and does not need to be permanently installed.

• Portable air conditioners cum refrigerator are oftentimes more affordable than traditional units and will usually not incur installation costs

• Portable air conditioners cum refrigerator do more than just cool.

• Affordable - Portable air conditioners cum refrigerator are oftentimes more affordable than traditional units and will usually not incur installation cost.

Limitation •Since only one refrigerant is used throughout the system, the

refrigerant used should have high critical temperature and low

freezing point.

• The operating pressures with a single refrigerant may become

too high or too low. Generally only R12, R22 and NH3 systems

have been used in multi-stage systems as other conventional

working fluids may operate in vacuum at very low evaporator

temperatures. Operation in vacuum leads to leakages into the

system and large compressor displacement due to high specific

volume.

5.CONCLUSION

• The present invention provides an air-conditioning cum refrigerator designed to satisfy the need.

• The scope of refrigeration is very wide and applications are very diverse and literally thousands of scientists and engineers have contributed towards its development

• One of the efforts towards this accomplishment is compatible A.C. cum Refrigerator which can be used for refrigeration as well as air conditioning

REFERENCES

• Ricky G. Ledbetter, “Air-Conditioning Refrigerator”, United States Patent, Patent No: 4821530, April 18, 1989.

• Venkatesh Kumar Sharma, Raj Kumar, Rahul Kumar, Vidhan Kumar, Jyoti Kumar, “A Hybrid System for Power Refrigerate & Air Conditioning System By Renewable Source of Energy”, Dr. MGR University, ISSN (Print): 2278-8948, Volume-1, Issue-2, 2012.

• M. P. Goodson and C. W. Bullard, “Refrigerator/Freezer System Modeling”, A National Science Foundation/University Cooperative Research Center, ACRC TR-61, August 1994.