refrigerant used in cascade refrigeration mcq

Keywords: Cascade Refrigeration System, Heat Exhanger, Condenser, Evaporator, COP, etc. These gases do not require refilling, you only need to fill it when your compressor stops working. Can't read the image? www.gtu-mcq.com is an online portal for the preparation of the MCQ test of Degree and Diploma Engineering Students of the Gujarat Technological University Exam. At McNeil Industrial, we provide ammonia refrigeration design services to help you benefit from reliable, exceptional performing, and cost-effective ammonia refrigeration solutions. However, if carbon dioxide is used as a part of a cascade refrigeration system, it can be used at lower pressures. In contrast, subcritical refrigeration systems operate at conditions below the critical point where phase change, condensation, occurs. In air-conditioning of aeroplanes,using air as refrigerant,the cycle is used is....... You can send your comments directly at info@mechanicaltutorial.com. Fig. The phase diagram for CO2 is shown in Figure 1.Figure 2 is a pressure-enthalpy diagram for R-134a in a traditional vapor compression refrigeration cycle. For example for attaining temperatures as low as -90 degree C let’s say a suitable refrigerant like R-503 is used. Two-three-four stage systems are in … 17. Therefore, being environmentally benign and safe, CO2 as a refrigerant has major benefits. 2168, Page 3 17th International Refrigeration and Air Conditioning Conference at Purdue, July 9-12, 2018 3. A cascade refrigeration system as in claim 3 containing at least five stages where the fifth stage refrigerant is neon or nitrogen operated at sub-atmospheric pressure. 16. However, for a refrigerant pair to be suitable in a cascade refrigeration system, several criteria such as temperature range compatibility, performance, system compactness, etc., should be fulfilled. Ans: b 2. 1. Enter the code above here : R134a). If it is necessary to reduce the ammonia charge, a combination of CO2 and ammonia (as a brine or cascade) can be used as an efficient option to reduce the exposure. www.gtu-mcq.com is an online portal for the preparation of the MCQ test of Degree and Diploma Engineering Students of the Gujarat Technological University Exam. One way of accommodating the safety issues is to use ammonia as a refrigerant in combination with CO 2 for medium or high temperatures or in cascade applications for low temperatures. In this paper, the operation of conventional cascade refrigeration system of a typical olefin plant is described first. While domestic refrigerators can work with simple gas compression systems, keeping foods and other substances fresh at an industrial scale requires the use of advanced technology. The refrigerant used is (A) Ammonia (B) Carbon dioxide (C) Freon (D) Brine. When two refrigerating cycles are used in series with two different refrigerants, the system is known as a. dual refrigeration system b. cascade refrigeration system c. vapour absorption refrigeration system d. none of the above View Answer / Hide Answer A cascade system consists of two refrigeration circuits, with one higher boiling refrigerant (propane) being used to condense a lower boiling refrigerant (ethane or ethylene). (d) alcohol. The refrigeration requirement may be to chill a certain flow rate of a given fluid from one temperature to another. There are several benefits provided by ammonia, which has been demonstrated over a period of decades to be effective when used in ammonia refrigeration systems. of compressor ) more/less depending on 11.3 . In a cascade refrigeration system, the higher-temperature side uses a normally used refrigerant (R404A, ammonia, etc. www.gtu-mcq.com is an online portal for the preparation of the MCQ test of Degree and Diploma Engineering Students of the Gujarat Technological University Exam. The highest temperature during the cycle,in a vapour compression system,occures after ....... 20. Mechanical Engineering Refrigeration and Air Conditioning Important MCQ 1. Vapour Compression Refrigeration Cycle - MCQs with Answers Q1. If the evaporator temperature of a plant is lowered, keeping the condenser temperature constant, the h.p. Contact us: info@mechanicaltutorial.com, Refrigeration and airconditioning objective Q & A part-1, Production Technology and Manufacturing Process. Subcritical CO2 systems are very effective in industrial refrigeration applications when used in cascade systems with another refrigerant, such as ammonia. which will improve your skill. d) Same refrigerant has to be used for each stage of the Cascade system. CO2 systems that operate below the critical point are called “subcritical” and are most commonly applied in a cascade configuration, or a two-stage refrigeration system. Click here to refresh, © 2015 - 2020 MechanicalTutorial.com This Content is copyrighted By MechanicalTutorial.com |All Rights Reserved. 1. Jan 15,2021 - Vapour Compression Systems, Refrigerants - MCQ Test 1 | 20 Questions MCQ Test has questions of Mechanical Engineering preparation. Industrial refrigeration. (a) oxygen. Answer B 2. In cascade systems: a) Different refrigerants are used in individual cascade cycles b) There is no mixing of refrigerants and no migration of lubricating oil c) Higher COPs compared to multi-stage systems can be obtained d) Operating pressures need not be too high or too low Ans. A typical cascade refrigeration schematic is shown in Fig. The sub-cooling in a refrigeration cycle .... 19. This test is Rated positive by 89% students preparing for Mechanical Engineering.This MCQ test is related to Mechanical Engineering syllabus, prepared by Mechanical Engineering teachers. Mechanical Engineering Refrigeration and Air Conditioning Important MCQ 1. 14. The solved questions answers in this Test: Refrigeration And Air Conditioning -1 quiz give you a … Refri… The low stage uses CO2 and the high stage uses a different refrigerant (like NH3). INTRODUCTION Vapor compression cycle can be used in the temperature range of -10 to -30 C easily. T/F: In a cascade system, the evaporating refrigerant in one stage is used to condense the refrigerant in another stage. ASWDC (App, Software & Website Development Center) Darshan 7) 8) Consider a refrigerator that operates on the vapor compression refrigeration cycle with R-134a working fluid. Page-7 section-4 A cascade system is similar to a two-stage R-22 or ammonia system in its application. A refrigerant should have (a) Tow specific heat of liquid (b) high boiling point (c) high latent heat of vaporisation (d) higher critical temperature (e) low specific volume of vapour. Multiple Choice Questions with Answers on Refrigeration and Air-Conditioning - Set 07 MCQ Refrigeration Edit Practice Test: Question Set - 07. This prevents coagulation of the refrigerant due to very low temperature in the low temperature cycle. During a refrigeration cycle, heat is rejected by the refrigerant in a. Which device is used for the expansion of refrigerant in vapour compression refrigeration cycle? The ultra-low temperature refrigerant A cascade system typically operates with evaporator temperatures between –40°F and –150°F (–40°C and –100°C). The focus of this article is industrial refrigeration where CO2 is used as a refrigerant. Refrigeration And Air Conditioning MCQ question is the important chapter for a Mechanical Engineering and GATE students. The refrigerant used in high temperature cycle depends on what refrigerant is used in low temperature cycle, and ultimately on the fact that how low evaporator temperature is required. Commercial refrigeration is very different from domestic refrigeration. 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. Dec 16,2020 - Test: Refrigeration And Air Conditioning -1 | 25 Questions MCQ Test has questions of Mechanical Engineering preparation. However, contrary to HFCs, its GWP is negligible when applied as a refrigerant. (c) neon. 5. Explanation are given for understanding. Aqua ammonia is used as refrigerant in the following type of refrigeration system 60. Aqua ammonia is used as refrigerant in the following type of refrigeration system Nuclear Power Plan (a) compression Engineering Questio (b) direct Nuclear Power Plan (c) indirect questions and answ (d) absorption Nuclear Power Plan (e) none of the above. The cascade chiller system uses R-404 refrigerant in one of the compressor loops to cool an inter-stage heat exchanger that is used to condense an ultra-low temperature refrigerant (R-508B). Using carbon dioxide in cascade refrigeration systems also means that the aforementioned benefits of availability and low price are applicable for a cascade system. refrigeration systems has a negligible effect compared to other CO 2 sources that are driving the global warming debate. The major challenges in CO2 refrigeration involve the relatively high working pressures. They range in size from those used in refrigerated display D. One tonne of ice when melts from at 0 0 C in 24 hours,the refrigeration effect produced is equivalent to 210 kJ/min : a), b) and d) 7. Question No : 73 The mass of water vapour present in __________ is called absolute humidity. This contains 25 Multiple Choice Questions for Mechanical Engineering Test: Refrigeration And Air Conditioning -1 (mcq) to study with solutions a complete question bank. ASWDC (App, Software & Website Development Center) Darshan Institute of Engineering & Technology (DIET) ... Refrigeration and Air Conditioning (2161908) MCQ. Saturated liquid. Condenser. Refrigeration and Air Conditioning MCQ Questions 1-One ton of refrigeration is equal to (A) 21 KJ/min (B) 105 KJ/min (C) 210 KJ/min (D) 420 KJ/min 2-A low side float valve maintains the level of refrigerant in (A) Flooded evaporator (B “Subcritical” refers to refrigeration systems that operate entirely below the critical pressure. Fig. 2. One tonne of refrigerant is used. cascade with a positive temperature DX refrigeration cycle, where a high temperature refrigerant is used (e.g. THEORETICAL INVESTIGATION OF CYCLES 3.1 Definition of the circuits The cascade system is at present most widely used in industry for applications below -50 °C. 6. Part of the design process is to choose the type of system, which may be a multistage plant using a single refrigerant or a two-circuit cascade system using a high-pressure refrigerant for the low-temperature circuit. Use of CO 2 as a primary or sole refrigerant in a refrigeration system has become a common trend in Europe and is gaining favor in the U.S. CO 2 is primarily used in cascade systems that include ammonia, in booster systems in supermarkets, and as a stand-alone refrigerant for transcritical-configured systems. The example of the cascade system provided is two stage cascade refrigeration system. A cascade refrigeration system for installation where the machinery of the system is remote from the cooled space, in which an insulated bypass conduit withdraws at least some of the refrigerant avail CO2 cascade systems facilitate energy-efficient refrigerants, minimize risk. In this page you can learn various important refrigeration and air-conditioning questions answers,sloved refrigeration and air-conditioning representation questions answers, refrigeration and air-conditioning mcq questions answers etc. Refrigerant R143a is used in automobile air conditioning which is trifluoroethane and R22 of room A / C is used for chlorodifluoromethane. Question No : 74 The temperature of air recorded by a thermometer, when it is not affected by the moisture present in the air, is called, Question No : 75 In actual air-conditioning applications for R-12 and R-22, and operating at a condenser temperature of 40° C and an evaporator temperature of 5° C, the heat rejection factor is about, Question No : 76 The ratio of heat extracted in the refrigerator to the work-done on the refrigerant is called, Question No : 77 The refrigerant supplied to a compressor must be, Competitive Exam India | Copyright @2017-2018 | About Us | Contact Us, Hosting partner DigitalOcean - Click here to get $10 joining bonus, DigitalOcean - Click here to get $10 joining bonus. Refrigeration And Air Conditioning MCQ question is the important chapter for a Mechanical Engineering and GATE students. In a cascade refrigeration system, two or more vapor-compression cycles with different refrigerants are used. In a cascade system the high/medium temp refrigerant circuit is used to cool the condenser of the low temp circuit by way of a heat exchanger. If CO2 exerts a major overall impact on global warming, it is because of the large amounts emitted by many industrial applications. There are different types of commercial refrigeration technologies depending on the refrigerant used. Page-3 section-1 Page-3 section-1 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.

Department Of Justice Sheriff Vacancies, Golf 8 R Kw, Ucla Public Policy, Altra Torin Women's Size 9, Mighty Sparrow Net Worth, The Office Blu-ray Best Buy, Bmtc Bus Pass Online, Conjunction Games For Middle School, In Repair Solo Tab,

About the author:

Leave a Reply

Your email address will not be published.