SREE NARAYANA GURUKULAM COLLEGE OF ENGINEERING
DEPARTMENT OF MECHANICAL ENGINEERING
Certified that the project report “DESIGN AND FABRICATION OF PLATE FREEZER” is the bonafide work done by “LIJUSH PAUL, MIDHUN MOHAN, RAJESH K R, SUNIL K K” in the year 2008-2009, for partial fulfillment of B-Tech degree “ MECHANICAL
Dr. T. P. LUKOSE Head of the Department.
Mr. ARUN MOHAN Lecturer
Submitted for the Viva Voce Examination on ………………….
Name & Signature of Internal Examiner
Name & Signature of External Examiner
First of all we would like to thank God Almighty for all the blessings bestowed upon our team without which the work would not have been a reality. We extend our sincere thanks to Dr. T.P. Lukose, Head of the Department, Mechanical Engineering, Sree Narayana Gurukulam College of Engineering for his whole hearted support. We express our sincere gratitude to our guide Mr.Arun Mohan Lecturer, Department of Mechanical Engineering, Sree Narayana Gurukulam College of Engineering, for his advice and encouragement which were indispensable for the fulfillment of this project work. We are very much thankful to Mr. Rajesh Kumar R, our group tutor for his guidance in performing this project work. Also to Mr. P. P. Binu Heat Engines Laboratory In charge, for his kind support.
Last but not the least; we thank all other faculty members of Mechanical Engineering department and our friends for their help and support.
LIJUSH PAUL MIDHUN MOHAN RAJESH K R SUNIL K K
Techniques of freezing vary for each application, The type of refrigeration used for preserving fruits cannot suit the need of the fish industries. Later it has been discovered that the number of viable vegetative microorganisms in food are usually greatly reduced by freezing if quick freezing is employed. The conventional freezers could not cope with this higher rate of freezing. By the development of the plate freezer, the challenge of quick freezing has been met to enhance effective preservation. Plate type evaporators may be used in single or in banks. The plates may be manifolds for parallel flow of the refrigerant or they may be connected for series flow. Plate evaporators are especially useful used for liquid cooling installation where unusual peak load conditions are encountered periodically. In the present work, a plate freezer consisting of two plates connected in parallel and having a cooling load of 0.335 KW is to be designed. Installing formed tubing between two metal plates, which are brazed together at the edges, forms the plate surface evaporators. The refrigerant used is R-134a a refrigerant which is now used as a replacement for R-12.
TABLE OF CONTENTS
ABSTRACT LIST OF TABLES LIST OF FIGURES NOMENCLATURE
iv vii viii ix
2 2.1 2.2
CARNOT CYCLE VAPOUR COMPRESSION CYCLE PERFORMANCE OF THE STANDARD VAPOUR COMPRESSION CYCLE
3 5 8
3 3.1 3.2 3.3 3.3.1 3.3.2 3.4 3.5 3.6 3.6.1 3.6.2 3.6.3 3.6.4 3.6.5 3.7 3.8 3.8.1
SYSTEM DESIGN COOLING LOAD CALCULATIONS
DESIGN AND SELECTION OF PLATE FREEZER COMPONENTS 13 REFRIGERANT SELECTION REQUIREMENT OF THE REFRIGERENT REFRIGERANT 134a(R 134a) INSULATION DESIGN OF COMPRESSOR DESIGN OF CONDENSOR TUBE SELECTION REFRIGERANT SIDE HEAT TRANSFER COIFFICIENT AIR SIDE HEAT TRANSFER COEFFICIANT OVERALL HEAT TRANSFER COEFFICIANT CONDENSOR SELECTION DESIGN OF EXPANTION DEVICE EVAPORATOR DESIGN OUTSIDE HEAT TRANSFER COEFFICIANT v 13 13 15 16 17 19 20 20 21 22 24 25 28 29
3.9 3.10 3.11
FABRICATION OF EVAPORATOR PLATES DRIER FILTER ACCUMULATOR
31 32 33
4 5 6 7 8 9
TEMPERATURE MEASUREMENTS PRESSURE MEASUREMENTS EXPERIMENTAL ANALYSIS OF THE SYSTEM SCOPE OF FUTURE WORK CONCLUSION REFERENCES
34 35 36 38 39 40
LIST OF TABLES
3.1 Refrigerant criteria 3.2 Selected compressor specification 3.3 Selected condenser specification 3.4 Designed evaporator specification 4.1 Pressure indicating coil 5.1. Experimental analysis of the system
15 18 23 31 35 36
LIST OF FIGURES
1.1. Conventional evaporator 1.2 Flat plate evaporator 2.1 Carnot vapor compression system 2.2 Thermo dynamic model of heat pump 2.3 Theoretical vapor compression cycle 2.4. Flow diagram of plate freezer 3.1 Compressor 3.2 Cross section of compressor 3.3 Condenser with fan 3.4 Disassembled view of the condenser 3.5 Expansion valve 3.6 Evaporator plate 3.7 Drier filter 3.8 Accumulator 3.9 Pressure gauges
1 2 3 4 6 9 17 18 19 24 25 28 32 33 35
Efficiency Degree Celsius Coefficient of performance Logarithmic mean temperature difference Thermal conductivity Reynolds number Prandtl number Nusselt number
COP LMTD K Re Pr Nu