57 In a lithium bromide absorption refrigeration system A Lithium bromide is used as a refrigerant and water as an absorbent. In this study, the effects of critical operational constraints on the operational domain of a double-effect lithium bromide/water absorption refrigeration system and its performance were investigated. In the absorber, the lithium bromide absorbs the water refrigerant, creating a solution of water and lithium bromide. B Water and lithium bromide . Ammonia or water is used as the vapor in commercial absorption cycle systems, and water or lithium bromide is the absorber. The power required to drive the plant is, The alignment circle is marked on the psychrometric chart at, The evolution of heat of solution takes place in ammonia absorption plant when, Refrigeration and Air Conditioning - Section 1, Refrigeration and Air Conditioning - Section 2, Refrigeration and Air Conditioning - Section 3, Refrigeration and Air Conditioning - Section 5. comprises of all the processes in the vapor compression refrigeration system like compression Water is used as a refrigerant and lithium bromide as an absorbent, C. In a water-lithium bromide vapor absorption refrigeration system, water is used as the refrigerant while lithium bromide (Li Br) is used as the absorbent. the last 5 years. Chain Drives MCQ Practice Test: 1. A Water and water . Each Section contains maximum 70 questions. it is having lot more of advantages like except for two small centrifugal pumps, there are no moving parts so less number of moving parts Lithium bromide is used as a refrigerant and water as an absorbent, B. Other types of charts showing vapour pressure data for water-lithum bromide systems are also available in literature. An interesting point to note about absorption chillers is that they don’t use conventional refrigerants. In a water-lithium bromide vapor absorption refrigeration system, water is used as the refrigerant while lithium bromide (Li Br) is used as the absorbent. The Li-Br solution has a strong affinity for water vapour because of its very low vapour pressure. For this analysis a typical house is modelled for a full year. Answer: Option B Weak solution mixes with strong solution. 26°C DBT and 60% RH, A. Most of the domestic refrigerators work on the following refrigeration system, In a lithium bromide absorption refrigeration system, The operating temperature of a cold storage is -2°C. Water is being used as refrigerant whereas Li-Br is a highly hydroscopic salt, used as absorbent. Heat for the vapour absorption refrigeration system can be provided by waste heat extracted from the process, diesel generator sets etc. An important characteristic of absorption system of refrigeration is (a) noisy operation (b) quiet operation (c) cooling below 0°C absorber, generators and an evaporator. None of the above, A. Lithium Bromide Absorption Unit Water is used as a refrigerant in the lithium bromide absorption cycle. These constraints were determined as the equivalence state of concentrations, the thermal unbalance between the system components of high-pressure condenser and low-pressure generator, … An important characteristic of absorption system of refrigeration is (A) Noisy operation (B) ... Lithium bromide used in vapour absorption cycle is non volatile (B) Lithium bromide plant can't operate below 0°C ... Chain Drives Multiple Choice Questions and Answers. Figure 2-38 is a schematic representation of an absorption refrigerated inlet system for the gas turbine. Water is used as a refrigerant and lithium bromide as an absorbent C. Ammonia is used as a refrigerant and lithium bromide as an absorbent D. None of the above. Refrigeration & Air-Conditioning MCQ with detailed explanation for interview, entrance and competitive exams. Figure 15.3 shows another chart wherein the mass fraction of lithium bromide is plotted on abscissa, while saturation Instead they use water as the refrigerant, and this is mixed with either ammonia or Lithium Bromide. In a lithium bromide absorption refrigeration system. Vapour compression, B. Figure 15.2 shows the water-lithium bromide based absorption refrigeration system on Dühringplot. Ans: a. 14. In a water-lithium bromide vapor absorption refrigeration system, water is used as the refrigerant while lithium bromide (Li Br) is used as the absorbent. The working temperature of the generator, adiabatic absorber, condenser, evaporator, the cooling capacity of the system, and the Ammonia-absorption refrigeration cycle requires (a) very little work input (b) maximum work input (c) nearly same work input as for vapour compression cycle (d) zero work input (e) none of the above. In that case absorption systems … Explanation are given for understanding. The following are the two principles that form the basis for the lithium bromide absorption refrigeration cycle: 1. Ammonia is used as a refrigerant and lithium bromide as an absorbent, D. Water under low pressure is evaporated from the coils that are to be chilled. In the absorber, the lithium bromide absorbs the water refrigerant, creating a solution of water and lithium bromide. B Water is used as a refrigerant and lithium bromide as an absorbent. This closing of valve will reduce the heat input to generator of absorption chillers and temperature in generator will be reduced. In this system, water is being used as a refrigerant whereas lithium bromide, which is a highly hydroscopic salt, is used as an absorbent. Ammonia vapour is driven out of solution, C. Vapour absorption, C. Such systems can cool the inlet air to 50°F (10°C). Water is used as a refrigerant and lithium bromide as an absorbent, C. Ammonia is used as a refrigerant and lithium bromide as an absorbent, In case of sensible heating of air, the coil efficiency is given by (where B.P.F. 26°C DBT and 50% RH, C. Learn Refrigeration And Air Conditioning MCQ questions & answers are available for a Mechanical Engineering students to clear GATE exams, various technical interview, competitive examination, and another entrance exam. In this investigation, a thorough thermodynamic analysis of the water/lithium bromide absorption refrigeration cycle in the absence of solution heat exchanger is performed. In both systems the required refrigeration is provided by refrigerants vaporizing in the evaporator. analysis of an absorption refrigeration system equipped with an adiabatic absorber using a lithium-bromide/water (LiBr/water) pair as the working fluid. The … A solar absorption system consisting of a lithium bromide-water unit, a solar collector and a storage tank is modelled with the TRNSYS computer program using a typical meteorological year (TMY) for a hot climate (Nicosia, Cyprus). 1.1 Single Effect Lithium Bromide (LiBr) - Water Cooling The single effect absorption technology provides a peak cooling coefficient of performance (COP) of approximately 0.7 and operates with heat input temperatures in the range of 80°C to 120°C. 7.44 kW, D. A system in which a secondary fluid absorbs the refrigerant, releasing heat, then releases the refrigerant and reabsorbs the heat. A number of feasible methods for determining the concentration of aqueous lithium–bromide solution are imperative to review here. The lithium-bromide absorption refrigeration system uses a solution of lithium bromide in water. Lithium Bromide is more common because it is safer and non toxic, so we’ll look at how the water Lithium Bromide type chillers work. 5. To get more questions visit other sections. It should be noted that the refrigerant in the water-lithium bromide system is water = Bypass factor), The undesirable property of a refrigerant is, The desirable property of a refrigerant is, Related Questions on Refrigeration and Air Conditioning, More Related Questions on Refrigeration and Air Conditioning. @article{osti_638420, title = {A comparison between ammonia-water and water-lithium bromide solutions in vapor absorption refrigeration systems}, author = {Horuz, I}, abstractNote = {A Vapor Absorption Refrigeration (VAR) System is similar to a Vapor Compression Refrigeration (VCR) System. The water is absorbed by a lithium bromide/water solution. Absorption systems typically employ lithium–bromide (Li–Br) and water, with the Li–Br being the absorber and the water acting as the refrigerant. Conventional generator in lithium bromide absorption refrigeration system is too bulky and heavy to be fitted into small scale device, and the temperature of the driving heater in the generator seems much higher than low grade energy such as regenerative energy or waste heat energy. The absorption system differs from the compression-type refrigeration machines. A simple absorption refrigeration system common in large commercial plants uses a solution of lithium bromide or lithium chloride salt and water. The lithium bromide solution has a strong affinity for water vapour because of its very low vapour pressure. The heat leakage from the surrounding is 30 kW for the ambient temperature of 40°C. The objective of this paper is to develop a mathematical model for thermodynamic analysis of an absorption refrigeration system equipped with an adiabatic absorber using a lithium-bromide/water (LiBr/water) pair as the working fluid. Pure water is sed as refrigerant and lithium bromide solution is used as u absorbent. Electrolux refrigerator, A. D None of these. In a lithium bromide absorption refrigeration system (A) Lithium bromide is used as a refrigerant and water as an absorbent (B) Water is used as a refrigerant and lithium bromide as an absorbent (C) Ammonia is used as a refrigerant and lithium bromide as an absorbent (D) None of the above it evaporates. of refrigeration plant used is one fourth that of ideal plant working between the same temperatures. The lithium bromide absorption refrigeration system uses a solution of lithium bromide in water. A. Lithium bromide is used as a refrigerant and water as an absorbent B. The influence of operating temperature on the thermal loads of components, COPc (Carnot Coefficient of Performance), COPE (Enthalpy based Coefficient of Performance) and efficiency ratio (η) is studied. 3.72 kW, C. Vapour absorption refrigeration systems using water-lithium bromide pair are extensively used in large capacity air conditioning systems. 6. Carnot cycle, D. 20°C DBT and 60% RH, D. C Ammonia is used as a refrigerant and lithium bromide as an absorbent. In aqua ammonia and Lithium bromide water absorption refrigeration systems, the refrigerants are respectively . The actual C.O.P. 20°C DBT and 50% RH, B. In the lithium bromide absorption system, the absolute pressure in the evaporator is approximately: A) 0.84 kPa B) 1.5 kPa C) 5.0 kPa The main aim of this work is to study of Lithium Bromide- Water (LiBr-H2O) absorption But as far as COP of these refrigeration systems is concerned, it System with the Capacity of 1.5 ton. The concentration of Lithium Bromide in an absorption refrigerating system will change while a) Going through the expansion valve b) Going through the suction valve c) Cooling through the heat exchanger d) Absorbing water vapour in the absorber e) going through the discharge valve In a lithium bromide absorption refrigeration system. Name the components of an absorption refrigeration system: Condenser, liquid receiver, expansion valve, pump. A. A. Lithium bromide is used as a refrigerant and water as an absorbent, B. A. Lithium bromide is used as a refrigerant and water as an absorbent. Abstract: This paper describes using the heat pipe exchanger replaces the traditional heat exchanger in the lithium bromide absorption-refrigeration system, and a LiBr solution physical properties computation procedure has been developed to predict the performance of an absorption refrigeration unit. Lithium bromide mixes with ammonia, D. In these systems water is used as refrigerant and a solution of lithium bromide in water is used as absorbent. Water-Lithium Bromide vapor absorption system Introduction • Vapor absorption refrigeration systems using water-lithium bromide pair are extensively used in large capacity air conditioning systems • water is used as refrigerant and a solution of lithium bromide in water is used as absorbent • It is used only in applications requiring refrigeration at temperatures above 00C Cont… 1.86 kW, B. Schematic diagram of a LiBr/water (lithium–bromide/water) absorption refrigeration system equipped with an adiabatic absorber [4]. Ammonia vapour goes into solution, B. 18.6 kW, A.