M E S S A G E ASHRAE INDIA CHAPTER P R E S I D E N T I A L BULLETIN. K.K. MITRA President ASHRAE India Chapter

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1 ASHRAE INDIA CHAPTER For the HVAC&R Industry August 2016 Volume 18 Issue 1 Editor : K.K. Mitra, Associate Editor : Dinesh Rawat BULLETIN The BOG for was installed on by respected Dr. Prem C. Jain. The BOG comprised of a well balanced team of Consultants, Manufacturers & Users. This time the BOG members are not only from Delhi but also from ASHRAE Sections of Jaipur, Chandigarh & Kolkata. The complete roadmap for the year was presented during the installation ceremony. The major events include AIC TECH Flagship Event in November, 2016 K.K. MITRA President ASHRAE India Chapter Participation in Technical Programs and conference like ACETECH Global Green Summit, Indian Green Building Congress, International conference by Jamia Milia Islamia, ACREX etc. Addition of new student chapters Technical seminars and quiz contest at Colleges Job Fair for Students P R E S I D E N T I A L M E S S A G E Under Sustainable activity, a Solar Cold Store shall be installed, which has already been developed and successfully tested at Delhi. Small Group Knowledge Workshops on specific topics will be taken up on regular basis. The trainers would be BOG members as well as outside faculty. Development of young members to take on responsibility in future, will be a major stress area this year and we pledge to develop new leaders for future. Efforts will be made to come out with more Technical Journals on HVAC. We will coordinate with other ASHRAE chapters to work on development of ASHRAE activities as a whole in India. This year we plan to organize ASHRAE meetings outside Delhi in places like Jaipur, Chandigarh, Dehradun etc. A close coordination will be maintained with ISHRAE local chapters and at National Level to successfully organize events jointly. A major achievement for all ASHRAE Chapters in India has been the selection for AVRC's from various chapters viz Mr. G.C. Modgil GGAC, ASHRAE India; Mr. V Krishnan CTTC, ASHRAE Mumbai; Mr. Yogesh Thakkar- Membership, ASHRAE Western India; Mr. G Ramesh Research, ASHRAE Bangalore. Our pledge would be to have more members from various Chapters nominated to Society positions to ASHRAE USA. In order to make our newsletter more adaptive, we are inviting articles from other ASHRAE chapters as well as other HVAC related associations. The class room education program started in the last edition, is being continued in the present edition. Regards, K.K. MITRA President - ASHRAE India Chapter

2 I nfocus Annual General Meeting and Installation Ceremony of AIC BOG The Annual General Meeting and Installation of the new BOG of AIC was held at The Theatre India Habitat Centre, Lodhi Road, New Delhi on 8th July, 2016, The oath to the new team was given by Hon'ble Dr. Prem C. Jain. AIC BOG Mr. K K Mitra President Mr. Kanagraj Ganesan Mr. Priyank S. Garg President Elect. Mr. Manoj Chakravorti Mr. Indrajit Bhattacharya Vice President Mr. Pankaj Sareen Dr. Rajinder Singh Mr. Dharmendra Rathore Mr. Uma Singh Jadon Dr. Varun Jain Mr. Abid Husain Mr. Sunil Bajaj Imm. Past President. Secretary Treasurer Mr. Subhasish Dasgupta Mr. S.S.Gangwar Mr. Ashu Gupta Mr. Raju Bhat (President Kolkata Section) (President Jaipur Section) Mr. Sunil Gupta, Chair - CTTC Mr. K.D.Singh, Chair - Research Promotion Dr. Rajinder Singh, Chair- Student Activities Mr. Dinesh Gupta, Chair - GGAC Mr. Indrajit Bhattacharya, Chair - Membership Promotion Mr. Ashu Gupta, Chair-YEA

3 A ctivities Chapter Activities Technical Workshop on 17th June, 2016 Technical Workshop on 16th July.,2016 ASHRAE India Chapter organised a full Day Technical Workshop on 17th June, 2016 at K-43, (Basement ), Kailash Colony, New Delhi , The topics of presentation were 'Best practices for operation and preventive maintenance of HVAC systems in Green Buildings' By Dr. Rajinder Singh, 'Energy Saving in Green Buildings by Insulation' By Mr. K K Mitra and 'Heat load Calculation' By Mr. U S Jadon. The event was appreciated by the participants. Yea Programme at Manali ASHRAE India Chapter organised a Full Day Technical Workshop on 'UNDERSTANDING REFRIGERANTS' by Mr. Kapil Singhal on 16th July.,2016 at Lodhi Road New Delhi, The event was well attended. Mexichem, India was the partner for the event. ASHRAE Distinguished Lecture ASHRAE India Chapter organized a tour programme at Manali from - 16th July 2016 to 19th July The event focused on technical session, YEAs meet-up with lots of fun & activities. In addition to this, a local sight-seen was conducted. Quiz Programme The 8th Sustainable Energy & Environment Quiz was successfully organized by Energy Club under the aegis of Center for Energy & Environment on 20th & 21st August, 2016 at MNIT Jaipur. The event was sponsored by ISHRAE and supported by ASHRAE India Chapter. A total of 277 teams from 13 different colleges across India had registered for the quiz. On the first day, a play titled 'Ummeed Nayi Subah Ki' was organized to convey the message of Energy Conservation from the Energy Club team in association with DIL (Dramatics Society of MNIT). ASHRAE Distinguished Lecture Programme was held at Poornima College of Engineering, Jaipur by DL Speaker Dr. Om Taneja on Future is the Smart Cities on 5th August.,2016 at Jaipur. The workshop was very well attended and appreciated by the participation. The occasion witnessed the presence of members from ASHRAE India and Jaipur section along with the faculty members of Mechanical Department, PCE. AIC BOG meeting was also held with the Jaipur Section members. IAQA India Chapter The India Chapter of IAQA the first chapter ever, outside of North America was launched on 26th of August, 2016 in Goa, India. At the launch, an MOU was signed with ISHRAE(Indian Society of Heating, Refrigerating& Air-conditioning Engineers) for sharing of knowledge and connecting with concerned industries. It was attended by about 150 delegates from all over India. A committee has been formulated with Richie Mittal as the Chapter Director and Viswanath Krishnan as Vice Chapter Director. The initiatives of the India Chapter are to develop the following guidelines: Parameters of good indoor air quality Identificationan effective home air purifier Formation of IAQA India Chapter - Stephanie, Richie, Donald and Krishnan The newly formed committee will work towards dissemination of knowledge and actively involve more organisations and people to improve air quality. By Richie Mittal, Chapter Director IAQA, India ASHRAE India Chapters coordination meeting was held at the Bogmalo Beach Resort, Goa on 27th Aug., Workshop on Productivity in Green Buildings WORKSHOP ON PRODUCTIVITY IN GREEN BUILDINGS was organised by IGBC in Jaipur under leadership of Dr Jyotirmay Mathur. The event was supported by ASHRAE Jaipur section.

4 A rticle Solar Milk Refrigerator Dr. Shishir Chand Bhaduri Prof, Dept of Mech Engg JK Lakshmipat University, Jaipur Mr. Shailendra Kasera HOD, Dept of Mech Engg Poornima College of Engineering, Jaipur India is the world's one of the largest producer of milk. It claims 20% of the world's total milk production. The milk preservation is a fast growing business in developing countries. High-energy cost and environmental concerns are two major issues in using the conventional energy sources. Besides, all the villages are not connected to the grid that's why refrigeration facility is not available. If the milk is exposed to high temperature for several hours, it will cause bacteria reproduction. Milk should be kept at a lower temperature to prevent bacteria reproduction and follow the permissible limit of bacteria content. At present, almost all dairy operations are performed using grid supply with the diesel generator as backup. If a village is not connected to the grid, then, it is difficult to preserve the milk. The village level co-operative societies for milk collections are provided by bulk milk coolers operating on conventional grid supply of electricity and in the case of unavailability of electric supply diesel generator sets are provided for cooling the milk. The problem of electricity and diesel generator sets can be solved by refrigeration system for cooling the milk based on renewable energy at society level. Milk Refrigerator using renewable energy may be one of the solutions to provide the refrigeration facility to rural areas. Solar energy can be used in either Vapor Absorption System or Vapor Compression Refrigeration System. Various solar operated vapor absorption systems are already reported and derelict the vapor compression system. Vapor compression system can be directly run by solar photovoltaic systems. It is simple in construction and has high power to weight ratio. It has no moving parts and simple to install. Photovoltaic array should produce sufficient power to run the refrigerator, as ample amount of solar irradiances are available in India. Studies reveal that solar PV should be designed by three times that of refrigerator load power. Crystalline silicon photovoltaic cell has high conversion efficiency from solar irradiance to electricity. It is a stand-alone solar photovoltaic system therefore; lead acid batteries with charge controller will be utilized. It is feasible to use the solar energy for Milk Refrigerator based on vapor compression system. In the case of refrigeration system, two different options for powering the compressor are either AC or DC. An AC current compressor is driven by alternative voltage such as 120 or 220 V and 50 Hz. On the other hand, DC compressor needs low voltage and direct current supply of V. Even though, DC compressor has similar type of mechanical compression element with AC compressor, it has a brushless electrical motor. Renewable energy technologies can be used to control a DC compressor directly while an AC compressor requires a power inverter. DC compressor provides a "soft-start" which means that the typical startup surge of an AC compressor running on an inverter is eliminated. A normal AC compressor will draw up to 500% more amps on startup, meaning that while running on an inverter, the inverter must be oversized accordingly. Oversized inverters are much less efficient. The DC compressor not only avoids needing an inverter, they also minimize the surge or spike at time of startup. Energy usage reduction through improved efficiency and use of renewable energy employing variable speed DC compressors is an advantage of such systems. R134a is being utilized in the domestic refrigerators, which solves the problem of Ozone Depletion Potential (ODP) but not Global Warming Potential (GWP). It has zero ODP but GDP100 of Similarly, R22 is going to be phased out. R290 (Propane) is natural refrigerant which may be one of the possible solution of ODP and GWP. R290 has zero ODP & 3 GWP100 and excellent thermodynamic properties. It has C boiling point and 96.70C critical temperature. It is compatible with mineral oil. Latent heat of vaporization of R290 is kj/kg and zero temperature glide but the most important concern is its flammability. It comes under A3 safety group. It should be taken into notice that millions of tons of hydrocarbon are used safely every year throughout the globe. R290 can also be used safely in refrigerator as it uses small quantity of charge around grams. Proper safety measures can solves the problem of flammability. This solar refrigerator is based on variable refrigerant flow (VRF) system. VRF system is a refrigerant system that varies the refrigerant flow rate with the help of the variable speed compressor and the electronic expansion valve. In this system, the compressor frequency and the electronic expansion valve opening is controlled simultaneously. In conclusion, this solar refrigerator can solve the problem of spoilage of milk and the same can be preserved for a long time. It is not dependent upon grid connection and fossil fuels. Solar energy is easily available in most of the parts of India. Milk refrigerator is utilizing the eco-friendly refrigerant. It not only promotes the renewable energy but also use of R290 solving the problems of Ozone Layer Depletion and Global Warming. DC variable speed compressor compatible with R290 refrigerant will be utilizing in this refrigerator. DC compressor has soft start and do not require power invertor. A VRF operation further improves its performance.

5 C lassroom Thermal Insulation of Buildings Buildings are large consumers of energy in all countries. In harsh climatic conditions, a substantial share of energy goes to the airconditioning of buildings. This airconditioning load can be reduced through many means; notable among them is the proper design and selection of building envelope and its components. The use of thermal insulation in building walls and roof does not only contribute in reducing the required air-conditioning system size but also in reducing the annual energy cost. Additionally, it helps in extending the periods of thermal comfort without reliance on mechanical airconditioning especially during interseasons periods. Therefore, proper use of thermal insulation in buildings enhances thermal comfort at less operating cost. However, the magnitude of energy savings as a result of using thermal insulation vary according to the building type, the climatic conditions at which the building is located as well as the type, thickness, and location of the insulating material used. The question now is no longer should insulation be used but rather which type and how much. Thermal insulation is an important technology to reduce energy consumption in buildings by preventing heat gain/loss through the building envelope. Thermal insulation is a construction material with low thermal conductivity, often less than 0.1W/mK. These materials have no other purpose than to save energy and protect and provide comfort to occupants. Of the many forms, shapes and applications of thermal insulation, this section focuses on those that are commonly used for building envelopes i.e., walls and roof Building insulation products are largely classified into two groups mineral fibre, cellular plastic. Mineral fibre products include rock wool, slag wool and glass wool. These materials are melted at high temperatures, spun into fibre and then have a binding agent added to form rigid sheets and insulation batts. If removed in appropriate conditions, mineral fibre can be reused and recycled at the end of its life. Cellular plastic products are oil-derived and include rigid polyurethane, phenolic, expanded polystyrene, and extruded polystyrene. The products are available as loose fill, rigid sheets and foam. Cellular plastic products can be recycled. It is more suitable for cellular plastic products to be incinerated for energy recovery at their end of life. Building envelope thermal insulation is a proven technology that contribute to energy efficient buildings. Feasibility of technology and operational necessities : In India, Energy Conservation building code include requirements to safeguard minimum acceptable insulation levels for building envelopes, and thus provide the opportunity for deploying the application of thermal insulation technologies. Therefore, a critical factor leading to large scale implementation of thermal insulation in India is to put in place supporting policies, both incentive and mandatory measures. The application requirements of most building envelope thermal insulation products include appropriate detailed design, good workmanship and appropriate product selection, handling and installation methods. Therefore, capacity building, such as workshops to train design professionals and construction work forces in these areas are required. Building envelope thermal insulation products are used in association with the construction details of floors, walls and roofs/ceilings for new building constructions and for retrofitting existing buildings. Good detailing and workmanship to prevent air leakage are crucial for all types of building envelope thermal insulation. It is important to pay additional attention to detail, when installing insulation materials at the electrical outlets and wiring inside walls, cutting and shaping the insulation materials to tightly enclose with the wall frame. Furthermore, as an overall quality control measure for building in extreme climatic conditions, it is recommended to have building envelope commissioning with attention paid to thermal insulation, especially in larger-scale buildings. How the technology could contribute to socio-economic development and environmental protection : The primary contribution of building envelope thermal insulation is to provide thermal comfort to its occupants. This supports healthy living environments and better productivity at workplaces. Thermal insulation reduces unwanted heat loss or heat gain through a building envelope. This, in turn, reduces energy demand for cooling and heating of buildings, and thus is a mitigation measure to reduce GHG emissions. Financial requirements and costs : Financial requirement for building envelope thermal insulation includes the costs of the products and their installation. The product and installation costs of thermal insulation are computed based on per unit of area and per unit of thermal conductivity value. Maintenance costs for thermal insulation products is low and not even required for cellular plastic products. In the case of mineral fibre, if the products do not perform as expected due to increased thermal conductivity caused by moisture or vermin infestation, replacement is required. For naturally-ventilated buildings in mild climatic conditions, roof insulation and westfacing wall insulation are the most effective methods of preventing heat gain through the building envelope, and thus have better return on investment compared to applying insulation to the entire building envelope. Cellular plastic products are rigid, stable and performed well in the long term. They require the least maintenance cost. Advantages of thermal insulation: Reduction of energy consumption for heating (by 30 % at least), Creation of a thermal comfort by increasing the surface temperature of the inside walls, Leaking elimination, Reduction of thermal stress of the framework, Building lifetime prolongation, By Dr. Sunil Bajaj ISOFOAM -INDIA AIC Improvement of the architectural look of the building The objective of this image is to address the impact of building envelope, effectiveness of thermal performance of buildings in hot/ composite climates. It emphasizes the role of insulation in achieving the desired objectives of reduction in heat flow through roof and wall.

6 C lassroom Refrigeration and Vapour Compression Refrigeration System (Cycle) for Refrigeration and Air-conditioning Engineers Dr. Rajinder Singh Senior Faculty, Pusa Institute of Technology, (Imm. Past President-ASHRAE India Chapter) 1.1 REFRIGERATION Refrigeration means production of cold and coldness is produced by abstraction (removal) of heat. Refrigeration is a process of moving heat from one location to another in controlled conditions. The work of heat transport is traditionally driven by mechanical work, but can also be driven by heat, magnetism, electricity, or other means. Fig.1.1 Refrigeration 1.2 VAPOUR COMPRESSION REFRIGERATION SYSTEM (VAPOUR COMPRESSION CYCLE) Vapor compression refrigeration system is the most widely used method for refrigeration used in domestic and commercial refrigerators, water coolers, large-scale warehouses for chilled or frozen storage of foods, ice plants, refrigerated trucks and refrigeration in oil refineries, petrochemical and chemical processing plants, natural gas processing plants etc. This system is used for air-conditioning of buildings like shopping malls, offices, hospitals, schools and colleges etc. This system is used for airconditioning of cars, buses and rail etc. 1.3 DESCRIPTION OF VAPOUR COMPRESSION REFRIGERATION SYSTEM (VAPOUR COMPRESSION CYCLE) The vapor-compression refrigeration system has four major components: evaporator, compressor, condenser, and expansion (or throttle) device. The most widely used refrigeration cycle is the vaporcompression refriger ation cycle. In an ideal vaporcompression refrigeration cycle, the refrigerant enters the compressor as a saturated vapor and is cooled to the saturated liquid state in the condenser. It is then throttled to the evaporator pressure and vaporizes as it absorbs heat from the refrigerated space. Fig.1.2 Ideal vapor-compression cycle The ideal vapor-compression refrigeration cycle consists of four processes. Process Description 1-2 Isentropic compression 2-3 Constant temperature heat rejection in the condenser 3-4 Throttling in a throttle device (expansion device) 4-1 Constant temperature heat abstraction (addition) in the evaporator The ideal vapor-compression refrigeration cycle is shown on the Pressure-Enthalpy (P-h) diagram (Fig. 1.3). Fig.1.3 Ideal vapor-compression cycle on the Pressure-Enthalpy (P-h) diagram Thus the refrigeration cycle comprises of: (1) Absorption of heat from the substance to be cooled by the evaporation of a liquid refrigerant in the evaporator at a controlled lower pressure. (2) Raising the pressure (to raise the condensing temperature) of the low pressure vapour coming from the evaporator, by the use of the compressor. (3) Removal /rejection of heat from the highpressure vapour in the condenser so as to liquefy or condense the vapour. (4) By the use of the throttling device, reducing the pressure of the high-pressure liquid (from the condenser) to the level of pres sure needed in the evaporator. These components are inter-connected by pipessuch a, evaporator to compressor by the suction line, compressor to condenser by the discharge or hot gas line and from condenser to throt tling device by the liquid line. In addition to raising the pressure of the vapour, the compressor also creates the pressure difference between the evaporator and condenser and thus maintain a continuous flow of the refrig erant through the system. 1.4 WORKING OF VAPOUR COMPRESSION REFRIGERATION SYSTEM Vapor-compression refrigeration system is a closed thermodynamic system and the working fluid used in this closed system is known as refrigerant. In this system compressor sucks low temperature low pressure refrigerant vapors from the evaporator and compresses to high temperature high pressure refrigerant vapors by application of work, after compression the refrigerant vapors are superheated. These high temperature high pressure superheated refrigerant vapors goes to the condenser, firstly these refrigerant vapors are desuperheated and then condensed to liquid refrigerant by rejecting latent heat to the atmosphere in case of air cooled condensers and rejecting the heat to cooling water in case of water cooled condensers, using cooling towers. Fig.1.4 Working of vapor-compression refrigeration system In rare cases the liquid refrigerant is sub-cooled in the condenser if the cooling water inlet temperature to condenser is lower or the flow rate of cooling water is higher. Sub-cooling is always advantageous. From condenser, the high-pressure

7 C lassroom liquid refrigerant enters the throttle device (expansion device or metering device) having narrow opening, expansion of refrigerant will takes place; pressure of the refrigerant is reduced. We get the cooling effect, after throttling the low temperature refrigerant is a mixture of liquid and the vapour part depend upon the pressure drop in throttling device, if pressure drop in more, more friction, more vapour formation. This low temperature refrigerant enters the evaporator and abstracting the heat from the food stuffs preserved in case of refrigeration or abstracting the heat from the space to be air-conditioned, evaporation of refrigerant will takes places, then again these low temperature low pressure refrigerant vapors sucked by the compressor. This cycle repeats again and again. This is known as vapour compression refrigeration cycle (system). 1.5 COEFFICIENT OF PERFORMANCE (COP) OF VAPOUR COMPRESSION REFRIGERATION SYSTEM Fig.1.5 Coefficient of performance of vapor-compression refrigeration system Coefficient of Performance of vapor-compression refrigeration system is defined as the ratio of net refrigerating effect to the compressor work. Coefficient of = Net refrigerating effect / performance (COP) Compressor work = N / W Net refrigerating effect (N) = m (h 1 h 4) Compressor Work (W) = m (h 2 h 1) Where (m) = mass flow rate of refrigerant h1 = specific enthalpy at compressor suction h2 = specific enthalpy at compressor discharge h3 = specific enthalpy at condenser outlet h4 = specific enthalpy after expansion 1.6 ACTUAL VAPOUR COMPRESSION REFRIGERATION SYSTEM (CYCLE) An actual vapor-compression refrigeration cycle involves irreversibilities in various components - mainly due to fluid friction (causes pressure drops) and heat transfer to or from the surroundings. As a result, the COP decreases. Differences Non-isentropic compression; Superheated vapor at evaporator exit; Sub-cooled liquid at condenser exit; Pressure drops in condenser and evaporator. In actual vapor-compression refrigeration cycle there is pressure drop in suction vapour in flowing through the suction line from evaporator to compressor inlet. Refrigerant vapours from evaporator flowing through suction valve, suction valve offers resistance, bulk volume of vapours is drawn through narrow opening of suction valve, there is wire drawing effect, its effect is pressure drop. Fig.1.6 Actual vapor-compression refrigeration system Suction is at low temperature and discharge of refrigerant is at high temperature, due to that cylinder walls are at high temperature. Hence there is heat transfer is from cylinder walls to suction, due to that there is increase in enthalpy. During compression, the temperature and pressure of the vapour refrigerant is increased. There is heat transfer from refrigerant to cylinder walls; hence there is increase in enthalpy. There is wire drawing effect during the passage of vapour refrigerant through discharge valve, its effect is pressure drop. There is pressure drop in discharge line because of frictional resistance to flow of refrigerant due to roughness of pipe. There is also pressure drop in condenser due to frictional resistance to flow of refrigerant. In liquid line there is also pressure drop due to frictional resistance to flow of refrigerant. In evaporator, there is pressure drop due to frictional resistance to flow of refrigerant. On changing from liquid to vapour, velocity of refrigerant is increased; its effect is pressure drop.

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