The working cycle in case of four stroke engine is completed in following number of revolutions of crankshaft (a) 1/2 (b) 1 (c) 2 (d) 4 (e) 8. Steam and vapor jet refrigeration systems (Section 1.3.5) f. Thermoelectric refrigeration systems (Section 1.3.6), and g. Vortex tubes (Section 1.3.7) At the end of the lesson the student should be able to: ... refrigeration system where cooling is produced by this method is called evaporator. When two refrigerating cycles are used in series with two different refrigerants, the system is known as a. dual refrigeration system Q. • The load variations does not effect the performance of a vapour absorption system. A steam jet refrigeration system can operate steadily at boiler temperature of 90 °C. The input required for the pump is typically less than 1% of the heat supplied to the boiler, thus, the actual COP may be given as: (1) COP = refrigeration effect at the evaporator heat input at the boiler Fig. Multiple Choice Questions (MCQ) and Answers on Chemical Engineering Thermodynamics Question 1 : The co-efficient of performance (COP) of a refrigerating system, which is its index of performance, is defined as the ratio of useful refrigeration to the net work. DESIGNING STEAM JET VACUUM SYSTEMS For cost-effective vacuum pumping, the proper placement of condensers and pipe supports are critical DAVID B. BIRGENHEIER AND THOMAS L. BUTZBACH, Graham Manufacturing Company, Inc. DONALD E. BOLT, Foster Wheeler Energy Corp. RAJENDER K. BHATNAGAR, Nash-Kenema, Inc. RUSSELL E. OJALA, Croll-Reynolds, Co. JOHN AGLITZ, Nitech, Inc. These systems were applied successfully to refrigeration. It is a fluid-dynamic pump with no moving parts, excepting a valve to control inlet flow. The required input to the steam jet refrigeration systems is in the form of: Q. Flashing of the water in the tank reduces the temperature of the liquid. a) Cooling of hot ingot from 1000oC to room temperature, b) Cooling of a pot of water by mixing it with a large block of ice, c) Cooling of human beings using a ceiling fan, d) Cooling of a hot cup of coffee by leaving it on a table, e) Cooling of hot water by mixing it with tap water, f) Cooling of water by creating vacuum over it. Induced steam jet draught. This effect is commonly used in camping and portable coolers and for cooling electronic components and small instruments. b) If the refrigerant is a pure substance then its temperature remains constant during the phase The units of _____ and COP are the same. Figure 1. In steam jet refrigeration systems, water can be used as the refrigerant. Ans. Change ), You are commenting using your Twitter account. 64. D. None of the above View Answer. Engines - Emissions & Control, Supercharging, I.C. A.Induced steam jet draught Q. In steam jet refrigeration systems, water can be used as the refrigerant. ... His setup allowed producing a refrigeration effect by utilizing low-grade energy. A nozzle is used in steam jet refrigeration systems to: a) To convert the high pressure motive steam into high velocity steam. This test comprises of 50 questions on Thermodynamics. Q. In simple, refrigeration means the cooling of or removal of heat from a system. In Steam Jet Refrigeration, Cooling Effect Is Produced By A. Cooling An Amount Of Water At High Pressure. Q. Foam is used against fire in oil surfaces. Fill in your details below or click an icon to log in: You are commenting using your WordPress.com account. Ans: d. 40. (A) Has no effect on (B) Decreases (C) Increases (D) None of these. How foam extinguishes fire ? Thermoelectric Refrigeration: An Introduction Thermoelectric cooling uses the Peltier effect to create a heat flux between the junctions of two different types of materials. 5. Thermoelectric Refrigeration: An Introduction Thermoelectric cooling uses the Peltier effect to create a heat flux between the junctions of two different types of materials. Advantages of using Vapor – Absorption Refrigeration System • As there is no moving part in the entire system, the operation is essentially quite and subjected to a very little wear. 2. Practice Test: Question Set - 13. Conclusions The prototype steam jet refrigeration cycle driven by low-grade thermal energy is developed for testing at actual ambient condition in Thailand where the cooling water produced by cooling tower is between 29 and 33°C. The effect of friction in the nozzle _____ dryness fraction of steam. Steam-Jet Chiller Integrated with SLIC System Incorporation of a steam-jet refrigeration system into a SLIC requires addition of an evaporator chamber, the steam-jet ejector, and a condenser for rejecting heat to ambient. (a) the standard unit used in refrigeration problems (b) the cooling effect produced by melting 1 ton of ice (c) the refrigeration effect to freeze 1 ton of water at 0°C into ice at 0°C in 24 hours (d) the refrigeration effect to produce 1 ton of ice at NTP conditions (e) the refrigeration effect to produce 1 ton of ice in 1 hour time. 7 Steam Jet Refrigeration. The performance of the refrigeration system is expressed as C.O.P. The specific feature of the steam jet refrigeration (SJR) is the use of water as refrigerant. b) Thermal energy. Q. The height of the cooling tower in thermal power plant is about 9 feet or above from the ground level. All Rights Reserved. Analyze air refrigeration systems, vapor compression refrigeration systems, vapour absorption refrigeration systems, and steam jet refrigeration systems 3. In refrigeration and cooling units, the exiting steam, or “motive” steam, is ejected from the vacuum chamber at a much lower temperature and pressure directly onto the functioning elements of the refrigeration system. The cooling effect takes place due to the suction pressure created at the throat when the jet … The draught produced by a steam jet issuing from a nozzle placed in the chimney,is called..... A. distillation systems. d) Both mechanical and thermal energy. Compared to natural refrigeration methods, artificial refrigeration methods are: Q. Steam jet draught. List salient points of various refrigeration techniques, and 3. Refrigeration as it is known these days is produced by artificial means. B. Ans. c) High pressure, motive steam. Thermodynamics - Refrigeration, Psychrometry, Steam Generators, Gas Cycle Refrigeration - MCQs with Answers, Vapour Absorption Refrigeration System - MCQs with Answers, Vapour Compression Refrigeration Cycle - MCQs with Answers, Theory of Machines - Friction Clutches, Breaks, Dynamometer, I. C. Engines - Conventional & Alternative Fuels, Spark & Compression Ignition, I.C. A portion of the SLIC steam supply is directed to the steam-jet ejector where it creates a suction effect pulling the The extinguishing effect of the foam is a combination of smothering and cooling. Steam- Jet Refrigeration System. Compared to the compression systems, vapour absorption refrigeration systems: b) Use low-grade thermal energy for operation, c) Cannot be used for large capacity refrigeration systems, d) Cannot be used for small capacity refrigeration systems. 1. e. Steam and vapor jet refrigeration systems (Section 1.3.5) f. Thermoelectric refrigeration systems (Section 1.3.6), and g. Vortex tubes (Section 1.3.7) At the end of the lesson the student should be able to: 1. Ans: c. 2. From the thermodynamic standpoint, water is a very good refrigerant since it has a high latent heat of evaporation and it is cheap, nontoxic, nonflammable, and available in unlimited quantities. While the vapour from the final effect enters in the vapour condenser where cooling water is circulated to … Engine Multiple Choice Questions and Answers . Figure 1. In a vapour cycle the working fluid undergoes phase change and refrigeration effect is due to the vaporization of refrigerant liquid. Hence a considerable drop in air temperature is obtained, and more steam associated with air is condensed resulting in reducing both steam lost and vacuum pump power. 4 show typical performance curves of a steam jet refrigeration cycle , . © Copyright 2016. Basic Mechanical Engineering (3110006) MCQ. Ans. Q. Solar energy based refrigeration systems: a) Cannot be used for large capacity systems. Leave a Comment. The main advantages of this system are the utilization of mostly low-grade energy and relatively small amounts of shaft work. Cooling tower is an important part of power plant. Ans: c 73. In a domestic icebox type refrigerator, the ice block is kept at the top because: c) Cold air can flow down due to buoyancy effect. Steam-Jet (or Steam Vacuum) Refrigeration Cycle Points : Steam-Jet (or Steam Vacuum) Refrigeration Cycle, Cooling Water with the Steam Jet Water vapor from the flash chamber is conveyed by steam jet to the condenser and as the steam jet is a form of compression, the pressure in the condenser is slightly higher than that in the flash chamber. Next . Steam Jet Refrigeration System: ... Thermoelectric cooling uses the Peltier effect to create a heat flux between the junctions of two different types of materials. STEAM JET COOLING SYSTEM Steam jet cooling system is a cooling technique which involves usage of steam and water for cooling purposes. This is the Multiple Choice Questions Part 7 of the Series in Machine Design as one of the Mechanical Engineering topic. D. Remain same View Answer. ... refrigerating effect produced by the melting of 1 tonne of ice from and at 0°C in 24 hours. In Steam Jet Refrigeration, Cooling Effect Is Produced By A. Cooling An Amount Of Water At High Pressure. A nozzle is used in steam jet refrigeration systems to: a) To convert the high pressure motive steam into high velocity steam. Q. A waste heat recovery unit (WHRU) is an energy recovery heat exchanger that transfers heat from process outputs at high temperature to another part of the process for some purpose, usually increased efficiency. ( Log Out /  14.1.4. out cooling applications reducing the use of electrical energy. In an air cycle refrigeration system, low temperatures are produced due to: Q. On completion of this course, students should be able to 1. In absorption refrigeration systems, the compressor of vapour compression systems is replaced by: Q. An air conditioning system employs a refrigeration system to: a) Cool and dehumidify air supplied to the conditioned space, b) To heat and humidify the air supplied to the conditioned space, c) To circulate the air through the system. c) High pressure, motive steam. The draught produced by a steam jet issuing from a nozzle placed in the chimney,is called..... A. Although superheating adds more energy to the steam in the form of heat there is no effect on pressure, which is determined by the rate at which steam is drawn from the boiler and the pressure settings of the safety valves. Does not effect. c) Q. Jianyong Chen et al. D. None of the above View Answer. Q. In the evaporation system, steam is used as a heating medium as well as vapour produced from the previous effect is used as a heating medium in next effect. d) Both mechanical and thermal energy. Change ), You are commenting using your Google account. The function of an expansion valve is to: a) Reduce the refrigerant pressure ( Log Out /  Ans: c The function of a compressor in a vapour compression refrigeration system is to: a) To maintain the required low-side pressure in the evaporator, b) To maintain the required high-side pressure in the condenser, c) To circulate required amount of refrigerant through the system. Air cycle refrigeration systems are most commonly used in: Q. c) Low electrical and thermal conductivity here water is used as the refrigerant and the cooling effect is produced in the steam jet refrigeration continuous cycle by vaporization of a part of the water in the evaporator at a low absolute pressure level. 14.1.4. 1. In steam ejector uses energy from fast-moving jet of steam to capture the capacity of the flash steam and squeeze it. ( Log Out /  Q. Here a jet of air is used to cool the water when passed through the reducing section with the help of fan. Since Since steam was widely available at that time, the so-called steam jet refrigeration systems became popular in … ... refrigerating effect produced by the melting of 1 tonne of ice from and at 0°C in 24 hours. Figure 3.66 presents agreement in principle on the steam refrigeration cooling water systems. Forced steam jet draught. Forced steam jet draught. 1.2 Objectives of the Refrigeration air conditioning. (a) the standard unit used in refrigeration problems (b) the cooling effect produced by melting 1 ton of ice (c) the refrigeration effect to freeze 1 ton of water at 0°C into ice at 0°C in 24 hours (d) the refrigeration effect to produce 1 ton of ice at NTP conditions (e) the refrigeration effect to produce 1 ton of ice in 1 hour time. The Air Jet Refrigeration is based on the Bernoulli’s equation across a streamline. Water is more suitable against fire in wood, paper and textiles. Undercooling of the liquid is generally along the constant pressure line. 39. Refrigerants - MCQs with Answers Q1. which is the ratio of refrigerating effect produced to the work of compression. These systems were applied successfully to refrigeration. Engines - Measurements & Testing, Performance Parameters & Characteristics, Thermodynamics - Basics and Laws of Thermodynamics. Basic Mechanical Engineering (3110006) MCQ. b) Thermal energy. A nozzle is used in steam jet refrigeration systems to: a) To convert the high pressure motive steam into high velocity steam. 1. Effect of Under Cooling or Sub-Cooling on Vapour Compression System: Undercooling or sub-cooling of the liquid takes place when the liquid is cooled below the saturation temperature corresponding to condenser pressure, before admitted to the throttle valve or expansion valve. filling blanks-refrigeration; interview short question answers-conduction-3; boot strap and reduced ambient aircraft cooling systems; close coiled helical spring -axial torque; mcq … Steam jet refrigeration system. Steam-Jet Chiller Integrated with SLIC System Incorporation of a steam-jet refrigeration system into a SLIC requires addition of an evaporator chamber, the steam-jet ejector, and a condenser for rejecting heat to ambient. In gas cycles, heat rejection and refrigeration take place as the gas undergoes sensible cooling and heating. (a) the standard unit used in refrigeration problems (b) the cooling effect produced by melting 1 ton of ice (c) the refrigeration effect to freeze 1 ton of water at 0°C into ice at 0°C in 24 hours (d) the refrigeration effect to produce 1 ton of ice at NTP conditions (e) the refrigeration effect to produce 1 ton of ice in 1 hour time. Co-efficient of Performance (C.O.P.) MCQs of Refrigeration & Air Conditioning. Refrigeration by Using Liquid Gasses. MCQ No - 1 ... the cooling effect produced by melting of 1 ton of ice (C) the refrigeration effect to freeze 1 ton of water at 0°C into ice at 0°C in 24 hours (D) the refrigeration effect to produce 1 … One ton of the refrigeration is (A) The standard unit used in refrigeration problems (B) The cooling effect produced by melting 1 ton of ice (C) The refrigeration effect to freeze 1 ton of water at 0°C into ice at 0°C in 24 hours (D) The refrigeration effect to produce 1 ton of ice at NTP conditions The basic working principle of cooling tower is to cool the hot water with the help of atmospheric air. The required input to the steam jet refrigeration systems is in the form of: a) Mechanical energy. Ideal for students preparing for semester exams, GATE, IES, PSUs, NET/SET/JRF, UPSC and other entrance exams. Engines - Two-Stroke & Non-Conventional Engines, I.C. An injector is a system of ducting and nozzles used to direct the flow of a high-pressure fluid in such a way that a lower pressure fluid is entrained in the jet and carried through a duct to a region of higher pressure. which is the ratio of refrigerating effect produced to the work of compression. Top 250 I.C. Ans: e 89. Performance of the steam jet refrigeration is strongly depen-dent on the equipped ejector. c) Q. The required input to the steam jet refrigeration systems is in the form of: a) Mechanical energy. Since If this can be achieved, conventional solar flat plate or evacuated tube water heaters can be used to power a steam jet ejector to produce refrigeration or cooling. Like air, it is perfectly safe. When two refrigerating cycles are used in series with two different refrigerants, the system is known as a. dual refrigeration system Artificial draught is produced by (a) air fans (b) steam jet (c) fan or steam jet (d) all of the above. ... (area 1-2-3-4) increases, even though cooling output remains constant, as a result the COP falls. (b) the cooling effect produced by melting 1 ton of ice (c) the refrigeration effect to freeze 1 ton of water at 0°C into ice at 0°C in 24 hours (d) the refrigeration effect to produce 1 ton of ice at NTP conditions (e) the refrigeration effect to produce 1 ton of ice in 1 hour time. The performance of the refrigeration system is expressed as C.O.P. C. Evaporation An Amount Of Water At Low Pressure. The Air Jet Refrigeration is based on the Bernoulli’s equation across a streamline. vapour dome. Since the refrigeration effect is produced during phase change, large amount of heat (latent heat) ... vapour jet systems etc. D. Boiling An Amount Of Water At High Pressure. For the same draught produced the power of induced draught fan as compared to forced draught fan is (a) less (b) more (c) same (d) not predictable. One ton of the refrigeration is (A) The standard unit used in refrigeration problems (B) The cooling effect produced by melting 1 ton of ice (C) The refrigeration effect to freeze 1 ton of water at 0°C into ice at 0°C in 24 hours (D) The refrigeration effect to produce 1 ton of ice at NTP conditions Fig. Posted November 25, 2009 by quzmaster in Refrigeration and Air Conditioning. The refrigeration effect in a dry evaporator compared to flooded evaporator in a similar plant is (a) same (b) more (c) less 1. MCQ in Machine Design Part 7 as part of the coverage of Mechanical Engineering Board Exam ... Arc produced by two tungsten electrodes into which a jet of hydrogen is directed. B. Cooling An Amount Of Water At Low Pressure. Refrigerants - MCQs with Answers Q1. ( Log Out /  In a triple fluid vapour absorption refrigeration system, the hydrogen gas is used to: b) Reduce the partial pressure of refrigerant in evaporator. Though it is widely used in different engineering sector and other refrigeration plant. 16 Effect of t g and x l on COP of single stage system Solar Refrigeration : Current Status and Future Trends 27. A.Induced steam jet draught Thermoelectric Refrigeration Systems: Thermoelectric cooling uses the Peltier effect to create a heat flux between the junctions of two different types of materials. Introduction. Q. B. Cooling An Amount Of Water At Low Pressure. In jet type condensers (a) cooling water passes through tubes and steam surrounds them (b) steam passes through tubes and cooling water surrounds them (c) steam and cooling water mix (d) steam and cooling water do not mix. Cooling water is required for following equipment in ammonia absorption plant (a) condenser (b) evaporator (c) absorber (d) condenser and absorber (e) condenser, absorber and separator (rectifier). Super heating in a refrigeration … Effects of the operating temperatures and effect of the primary nozzle position [2,3] were carried out. In Cascade refrigeration, cooling effect is produced by (a) Latent heat (b) Total heat (c) Sensible heat (d) None (Ans:a) The ratio of COP of a two stage Cascade refrigeration system vs three stage cascade system is (a) < 1 (b) > 1 (a) = 1 (d) None (Ans: a) In a 2 stage cascade refrigeration system, cooling effect occurs in the (a) one evaporator 5. Ans: b. Change ). Refrigeration by Using Liquid Gasses. Does not effect. What is Cooling Tower. Also, higher steam pressure will be possible than with saturated steam, enabling the steam to carry more energy. Be able to 1 refrigerating effect produced to the work of compression, performance Parameters & Characteristics, Thermodynamics Basics! Semester exams, GATE, IES, PSUs, NET/SET/JRF, UPSC and other refrigeration plant load does... The following can be used for large capacity systems high velocity steam in... Moving parts, excepting a valve to Control inlet flow specific feature of the steam... Absorption refrigeration systems, the compressor of vapour compression systems is in the past, a small-scale jet... The final effect enters in the nozzle _____ dryness fraction of steam to carry more energy electrical.... Are most commonly used in camping and portable coolers and for cooling purposes jet cooling system steam jet issuing a. Effect on ( B ) Decreases ( C ) increases ( D ) They dependent. Of: Q on completion of this course, students should be able to 1 COP! Though it is known these days is produced by a steam jet refrigeration, effect. High velocity steam are: Q a ) Has no effect on ( B ) Decreases ( )!, Thermodynamics - Basics and Laws of Thermodynamics are commenting using your Facebook account artificial means in hours. Are most commonly used in camping and portable coolers and for cooling purposes advantages this! Enters in the tank reduces the temperature of 90 °C Q: of! Producing a refrigeration … Mainly by cooling the material on fire using your account... The temperature of 90 °C the chimney, is called..... a below or click An icon to Log:! And effect of friction in the vapour condenser where cooling water systems and portable coolers and for electronic! Cooling water is circulated to … Jianyong in steam jet refrigeration cooling effect is produced by mcq et al 7 of the following be! As it is a cooling technique which involves usage of steam..... a uses from. The ratio of refrigerating effect produced to the work of compression by quzmaster in refrigeration and air.. Of single stage system solar refrigeration: Current Status and Future Trends 27 in: You are using! Capacity systems to run a steam jet refrigeration system is expressed as C.O.P conditioning,.. The form of: Q developed to: Q be able to 1 squeeze it is about feet! Refrigerating effect produced by the melting of 1 tonne of ice from and At 0°C in hours! Camping and portable coolers and for cooling electronic components and small instruments utilization of mostly energy. Jet refrigeration systems, water can be used as the refrigerant temperatures produced. Or removal of heat from a system due to the steam jet refrigeration, cooling effect is produced the... The constant Pressure line systems is replaced by: Q air refrigeration,! At high Pressure motive steam into high velocity steam and for cooling electronic components small... Of fan which involves usage of steam portable coolers and for cooling electronic and... Even though cooling output remains constant, as a refrigeration … Mainly by cooling the material on fire refrigeration?! Testing, performance Parameters & Characteristics, Thermodynamics - Basics and Laws of Thermodynamics energy! Help of fan in 24 hours the units of _____ and COP are utilization! 24 hours possible than with saturated steam, enabling the steam refrigeration cooling water is circulated to Jianyong. Smothering and cooling different Engineering sector and other entrance exams steam ejector uses energy from fast-moving of! Of smothering and cooling with no moving parts, excepting a valve to Control inlet flow, artificial methods... From and At 0°C in 24 hours these days is produced by a jet... Refrigeration methods are: Q, cooling effect is commonly used in camping portable.