Refrigeration and Air Conditioning: A Complete Guide by RC Arora PDF 182
Refrigeration and Air Conditioning by RC Arora PDF 182: A Comprehensive Guide
If you are looking for a comprehensive guide on refrigeration and air conditioning, you might want to check out Refrigeration and Air Conditioning by RC Arora PDF 182. This book covers all the aspects of refrigeration and air conditioning, from history to principles, from applications to design, from refrigerants to review. In this article, we will give you an overview of what this book has to offer, as well as some insights into the topic of refrigeration and air conditioning.
refrigeration and air conditioning by rc arora pdf 182
Refrigeration and air conditioning are two closely related fields that deal with the control of temperature, humidity, quality, and distribution of air in a given space. Refrigeration is the process of removing heat from a low-temperature region to a high-temperature region, while air conditioning is the process of treating air to provide comfort or desired conditions for humans or other purposes.
What is refrigeration and air conditioning?
Refrigeration is defined as "the science of providing and maintaining temperature below that of surrounding atmosphere" . Refrigeration can be achieved by various means, such as mechanical compression, absorption, evaporation, thermoelectricity, or magnetism. The main objective of refrigeration is to preserve food, medicine, or other perishable items, or to provide cooling for industrial processes or equipment.
Air conditioning is defined as "the process of treating air so as to control simultaneously its temperature, humidity, cleanliness and distribution to meet the requirements of the conditioned space" . Air conditioning can be classified into two types: comfort air conditioning and process air conditioning. Comfort air conditioning is designed to provide comfortable and healthy conditions for humans in residential, commercial, or public buildings. Process air conditioning is designed to provide suitable conditions for specific processes or operations in industrial, agricultural, or medical fields.
Why is refrigeration and air conditioning important?
Refrigeration and air conditioning are important for various reasons, such as:
They improve the quality of life and health of people by providing comfort, convenience, and hygiene.
They enhance the productivity and efficiency of various industries and sectors by enabling optimal performance of machines, processes, and workers.
They contribute to the conservation of natural resources and the protection of the environment by reducing food wastage, preventing spoilage, and minimizing greenhouse gas emissions.
What are the main components of refrigeration and air conditioning systems?
The main components of refrigeration and air conditioning systems are:
The refrigerant: the working fluid that absorbs and rejects heat in the refrigeration cycle.
The compressor: the device that compresses the refrigerant vapor and increases its pressure and temperature.
The condenser: the device that condenses the refrigerant vapor and releases heat to the surroundings.
The expansion device: the device that reduces the pressure and temperature of the refrigerant liquid.
The evaporator: the device that evaporates the refrigerant liquid and absorbs heat from the refrigerated space or the conditioned air.
These components are connected by pipes or tubes to form a closed loop. The refrigerant circulates through this loop, undergoing phase changes and heat transfers. The refrigeration cycle can be represented by a diagram on a pressure-enthalpy chart, as shown below:
The refrigeration system can be coupled with an air handling unit (AHU) or a fan coil unit (FCU) to provide air conditioning. The AHU or FCU consists of a fan, a filter, a coil, and a damper. The fan blows the air through the filter, which removes dust and impurities. The coil contains either hot or cold water or refrigerant, which heats or cools the air. The damper controls the amount and direction of the air flow. The AHU or FCU can be connected to a duct system that distributes the conditioned air to different zones or rooms.
History of Refrigeration and Air Conditioning
Refrigeration and air conditioning have a long and fascinating history that spans from ancient times to modern days. Here are some of the highlights of this history:
How did refrigeration and air conditioning evolve over time?
The earliest forms of refrigeration and air conditioning were based on natural phenomena, such as snow, ice, wind, water, evaporation, or salting. People used these methods to preserve food, cool drinks, or create comfort. For example, ancient Egyptians used wet reeds to cool their houses, ancient Romans used snow from mountains to chill their wine, ancient Indians used earthen pots filled with water to lower the temperature of their rooms, and ancient Chinese used ice cellars to store food.
The first artificial methods of refrigeration and air conditioning were developed in the 17th and 18th centuries, based on scientific discoveries and inventions. Some of these methods were mechanical (using pumps, pistons, valves, or cylinders), chemical (using solutions of salts or acids), or pneumatic (using compressed air or steam). Some of these methods were used for scientific experiments, medical purposes, or industrial applications. For example, in 1620, Cornelis Drebbel demonstrated an experiment of cooling air by evaporating water in a vacuum, in 1748, William Cullen produced artificial ice by evaporating ether in a vacuum, in 1758, Benjamin Franklin and John Hadley experimented with evaporation of volatile liquids to cool objects, in 1805, Oliver Evans designed a closed vapor-compression refrigeration cycle, in 1810, Sir John Leslie froze water by using an air pump and sulphuric acid, and in 1820, Michael Faraday liquefied ammonia by using high pressure and low temperature.
The first practical methods of refrigeration and air conditioning were developed in the 19th and 20th centuries, based on technological innovations and market demands. Some of these methods were electric (using motors, generators, or transformers), vapor-compression (using refrigerants, compressors, condensers, or evaporators), absorption (using heat sources, absorbers, or generators), or air cycle (using turbines, heat exchangers, or expanders). Some of these methods were used for domestic, commercial, or public purposes. For example, in 1842, John Gorrie built a prototype ice-making machine using compression, in 1851, James Harrison built a mechanical ice-making machine using ether vapor, in 1876, Carl von Linde patented a process for liquefying gases using ammonia, in 1902, Willis Carrier invented the first modern air conditioner using water-cooled coils, in 1913, Fred Wolf Jr. introduced the first domestic refrigerator using a small compressor, in 1922, Willis Carrier developed the centrifugal chiller using a safer and more efficient compressor, in 1928, Thomas Midgley Jr., Albert Henne, and Robert McNary synthesized chlorofluorocarbons (CFCs) as non-flammable refrigerants, in 1930, David Forbes Keith installed the first window air conditioner using a self-contained unit, in 1931, J. B. Priestley invented the first portable air conditioner using ice and a fan, in 1939, Packard introduced the first car with air conditioning using a dashboard switch, and in 1957, Robert C. Webber built the first geothermal heat pump using underground pipes.
What are some of the milestones and inventions in refrigeration and air conditioning?
Some of the milestones and inventions in refrigeration and air conditioning are:
William Cullen produces artificial ice by evaporating ether in a vacuum.
Oliver Evans designs a closed vapor-compression refrigeration cycle.
James Harrison builds a mechanical ice-making machine using ether vapor.
Carl von Linde patents a process for liquefying gases using ammonia.
Willis Carrier invents the first modern air conditioner using water-cooled coils.
Fred Wolf Jr. introduces the first domestic refrigerator using a small compressor.
Willis Carrier develops the centrifugal chiller using a safer and more efficient compressor.
Thomas Midgley Jr., Albert Henne, and Robert McNary synthesize chlorofluorocarbons (CFCs) as non-flammable refrigerants.
David Forbes Keith installs the first window air conditioner using a self-contained unit.
J. B. Priestley invents the first portable air conditioner using ice and a fan.
Packard introduces the first car with air conditioning using a dashboard switch.
Robert C. Webber builds the first geothermal heat pump using underground pipes.