Refrigeration fundamentals 2175 west park place blvd. Winery and other industrial refrigeration systems typically employ a vapourcompression cycle to achieve this, as illustrated in figure 1. The project will utilise the electrocaloric effect to develop new methods of. However, the cost, size, and complexity of refrigeration systems of the time, coupled with the toxicity of their ammonia coolants, prevented the general use of mechanical refrigerators in the. Know later, that refrigeration is an integral component of airconditioning. Ph diagram representation of a dry refrigeration cycle refrigerant fluid choice. Study of a refrigeration unit gas compressor refrigeration.
Cooling of water in the earthen pitcher the water coming out of the pores of the pitcher evaporates when it comes in contact with dry air, thereby. Saturation curve this curve represents what state vapor or liquid and region subcooled, latent heat, and superheat the refrigerant is in. Unit objectives after studying this unit, the reader should be able to define high, medium, and lowtemperature refrigeration. One ton of refrigeration is the refrigeration produced by melting one ton of ice at 32f in 24 hours. It is defined as the rate of heat transfer that results in the freezing or melting of 1 short ton 2,000 lb.
Basic cryogenic processes joulethomoson process, brayton process as well as claude process are described and compared. Purpose of refrigeration examples and applications choice of coolant and refrigerants phase diagram of water and co 2 vapor compression refrigeration system pressureenthalpy diagram for refrigerants refrigerator, air conditioner, thermoelectric cooler, heat pump designation, choice, criteria for selection, and. Matter held together to the extent it is considered one body. Determine the boiling temperature in an evaporator. Mechanical refrigeration developed in 1800s first practical refrigerating machine using vapor compression developed in 1834 basic closed cycle refrigeration system has changed very little since then early refrigerants included ammonia, sulfuric ether, sulfur dioxide, methyl chloride only ammonia secured a lasting role. This process can be as simple as placing a dish of strawberries in a snowbank or as. Baxter, oak ridge national laboratory, oak ridge, tn 378316070 abstract present supermarket refrigeration systems require very large refrigerant charges for their operation and can consume as much 11. Heat capacity is the change in heat content or enthalpy for one pound of material for one degree of temperature change. Comparative study of refrigeration systems for ice rinks.
Refrigeration manual, and follows part 1, fundamentals of refrigeration. The refrigeration cycles can also be represented in a ph diagram. Basic refrigeration cycle green, 2008 the capacity of a refrigeration unit is the rate at which heat is removed, expressed in tons of refrigeration. Objectives after studying this unit, you should be able to know what is refrigeration and airconditioning. Refrigeration vcr and vapour absorption refrigeration var. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Refrigeration systems in supermarkets with propane and. Downing technical consult, dupont company introduction refrigeration is the process of taking heat from someplace where it isnt wanted and disposing of it somewhere else. Most downloaded international journal of refrigeration. In order to insure the quality of the refrigeration oil in the compressor unit follow these recommendations. Refrigeration unit use please call outdoor recreation bldg 390 for more info8046338244 mwr outdoor recreation is maintaining two refrigeration units located beside the outdoor recreation center bldg 390. Guidelines for avoiding component failure in industrial refrigeration systems caused by abnormal pressure or shock 1. These refrigeration plants use gas, liquid, and mechanical energy to move heat from one place to another. Refrigeration fundamentals heatcraft worldwide refrigeration.
Paul reed the elements everything in, on, or around the earth, sun, moon and stars, including our bodies themselves, is made up of one or more of 92 basic elements. If the very cold material is slightly warmed by adding a little heat, the molecules begin to move somewhat, and the motion of the molecules becomes greater the warmer the material becomes. Improving winery refrigeration efficiency wine business. This law provides the basis of temperature measurement. Unit 3 refrigeration equipment refrigeration equipment.
Refrigeration and airconditioning is the subject which deals with the techniques to control the environments of the living and nonliving subjects and thus provide them comforts to enable them to perform better and have longer lives. The blast freezer freezes tuna and mackerel and the brine tunnel freezes sardine. If you as the refrigeration engineer had no criteria, constraints, direction, etc. Lab experiment on vapor compression refrigeration cycle experimented in chemical engineering department of bangladesh university of engineering and technology. Special university course for future engineers lecture notes. It teaches students how processes can be broken down into fundamental principles so that they can develop analytical skills, correctly analyze and troubleshoot systems, and embark upon successful careers as technicians. C using condensing waste heat using stable thermal heat source hc. Understanding the basic refrigeration cycle diagram also helps us to find subcooled, superheat and to troubleshoot refrigeration processes much easier. Refrigeration system selection question that was asked. Citescore values are based on citation counts in a given year e. One ton of refrigeration is defined as the quantity of heat removed tofreeze one ton of water into ice at 0oc in 24 hours. If an expander had been used the line from d to a would be a vertical line.
It is the rate of removing heat equivalent to 12,000 british thermal units per. A tone of refrigeration is expressed in designed as the rate of heat removed from the surroundings equivalent to the heat required for melting one tone of ice in one day 20140304 3 faculty of pharmacy, omer almukhtar university, tobruk, libya. Comparative study of refrigeration systems for ice rinks natural resources canada, 20 2 to assist ice rink owners in choosing the best refrigeration system possible, the study concludes with observations and comments made from canmetenergy experts based on the study results. Evaporative refrigeration makes use of the principle that when a liquid evaporates, it absorbs heat equivalent to its latent heat of vaporization from the surroundings, thereby cooling it. University of cantabria ghent university department of flow, heat and combustion mechanics head. Ys nn nn s7 style a codepak rotary screw liquid chillers.
Advances in supermarket refrigeration systems van d. When two systems are each in thermal equilibrium with a third system, then the two systems are also in thermal equilibrium with one another. Commercial refrigeration and air conditioning systems. In the past, this was done by collecting ice in the winter and using its specific heat to cool as the ice melted. Je tiens a remercier egalement jean marc fournier dabord pour lidee du sujet refrigeration.
The knowledge learned from the early research work on co 2 and safety of co2 in large refrigeration systems. However, all systems are subject to conditions created by design. Wet refrigeration cycle the expander has been substituted by a throttling valve. Some research work has been done through the race project for mobile air conditioning application amin, dienhart et al. The numerical figure is the same with either set of units.
Ph diagram representation of a dry refrigeration cycle. Refrigeration and air conditioning notes free download as word doc. Rev pages chapter 9 refrigerants, refrigeration cycles, and. Industrial refrigeration application and technology trends.
Study of a refrigeration unit free download as powerpoint presentation. Refrigeration and airconditioning is the subject which deals with the. Cylinder and piston mechanism and pv diagram of a reciprocating compressor where d is the bore or diameter and l is the stroke, i. Supermarket refrigeration and other large sized refrigeration systems are applications where co 2 is seen as a strong candidate to replace conventional options. It is intended to cover only the fundamentals of refrigeration theory and practice. This chapter gives an overview of the principles of low temperature refrigeration and the thermodynamics behind it. Units of refrigeration the practical unit of refrigeration is expressed in terms of tonne of refrigeration briefly written as tr. The refrigeration system is one of the most important systems in industry. When 1 pound of ice melts, it absorbs 144 btu, as latent energy. Hunters that want to temporarily store their harvested animal in these refrigerators may rent space, if room is available. It is defined as the ratio of the quantity of heat removed to the time taken.
This manual is designed to fill a need which exists for a concise, elementary text to aid servicemen, salesman, students, and others interested in refrigeration. Refrigeration working principle pdf plant but who wish to extend their knowledge on the basic principles of. Mechanical refrigeration developed in 1800s first practical refrigerating machine using vapor compression developed in 1834 basic closed cycle refrigeration system has changed very little since then early refrigerants included ammonia, sulfuric ether, sulfur dioxide, methyl chloride only ammonia secured a. Sep 28, 2015 capacity of refrigeration is expressed in tone. It is the principal element in coal, wood, paper, cloth, natural gas, gasoline. Ammonia in refrigeration systems ice arenas 1 p a g e ammonia in refrigeration systems in ice arenas the majority of ice arenas and curling rinks in canada use ammonia as a refrigerant in their refrigeration systems to cool the floors in their rinks and subsequently allow applied water to. We would like to get a consultants perspective on the entire refrigeration system and design process. Erik dick summary we design a refrigerating plant to freeze fish. The danfoss product range for the refrigeration and air. Our company offers high quality and efficient refrigeration plants includes ammonia refrigeration plant and freon refrigeration plant. The information included on refrigeration components is general in nature and is intended only to give a brief description of their operation. Welcome to the manual for refrigeration servicing technicians. Dairy refrigeration plants ammonia based refrigeration. Winery and other industrial refrigeration systems typically employ a vapourcompression cycle to achieve this, as illustrated in.
Engineering assessments of plant and associated equipment. A ton of refrigeration tr or tor, also called a refrigeration ton rt, is a unit of power used in some countries especially in north america to describe the heatextraction capacity of refrigeration and air conditioning equipment. Usually, one tends to pick pl as low as possible, but not below atmospheric. Refrigerants and the refrigeration system determine the pressures. Developers are constantly seeking for how to avoid the damage to the environment. High quality refrigeration oil is necessary to insure com pressor longevity and reliability. The refrigeration system of the supermarket uses the following refrigerants. At a lower temperature, molecular motion slows down and the growth of bacteria that causes food spoilage also retards. Mar 09, 2016 evaporative refrigeration makes use of the principle that when a liquid evaporates, it absorbs heat equivalent to its latent heat of vaporization from the surroundings, thereby cooling it. Manual for refrigeration servicing introduction technicians. Nov 29, 2012 one ton of refrigeration is defined as the quantity of heat removed tofreeze one ton of water into ice at 0oc in 24 hours.
Oil quality will rapidly deteriorate in refrigeration systems containing moisture and air or other contaminants. Refrigeration commissioning guide for commercial and industrial systems. It is an ebook for people who are involved in training and. Mechanical refrigeration works by changing the the majority of heat is removed from the the majority of the works by removedchanging the absorbed heat is state of the refrigerant. A tonne of refrigeration is defined as the amount of refrigeration effect produced by the uniform melting of one tone kg of ice from and at 0c in 24 hours. Detailed information as to specific products is available from manufacturers of components and accessories. A liquid, such as ammonia, which has a low boiling temperature, is allowed to pass into a space via tubing. A term applied in the industry to refer to the tubing or piping from the condenser to the expansion device. Vcr uses mechanical energy as the driving force for refrigeration, while var uses thermal energy as the driving force for refrigeration. A new project sets out provide a more economical, energy efficient and environmentally friendly cooling alternative. Refrigeration systems in supermarkets with propane and economy. An introduction to magnetic refrigeration request pdf.
807 1002 307 1436 1487 1367 25 71 242 464 361 1297 1070 897 1408 61 959 513 1376 870 102 418 811 253 1117 676 120 388 136 1055 542 692 303 1395 556 1423 823 715 23 490 58 1493