MECHANICAL SYSTEM Subject code -15BAR8.6
Kadeejath Shahana NU17UAR009
Mentor A r. S h o u m i k D e s a i
portfolio
Semester VIII
Nitte Institute of Architecture
CONTENTS P S Y C H R O M ET R I C C H A R T
O1110
Psychrometric Chart Design strategies Table Cooling strategies
COOLING SYSTEMS
11121
Radiant Cooling System Variable Radiant Flow Fan Coil System Dessicant Cooling System Split Air Conditioning System
H VA C L I NE D R AW I N G
22223
Variable Radiant Flow( VRF) Radiant Cooling System
L I F T S A ND E L E VAT O R S
24433
Lifts & Elevators Lift sub system Elevator Speeds Working of Escalator
Q U E S T I O NA I R S
34439
01
PSYCHROMETRIC CHART
Location:
Ahmedabad
Reference: https://drajmarsh.bitbucket.io/psychro-chart2d.html
Page No: 02 4 Page No: 2
Psychrometric Chart Psychrometric Chart
Psychrometric Chart Mechanical Systems
Strategy 1 How to achieve it Visuals Strategy 2 How to achieve it Visuals
What are the parameters that will change
January Internal heat gain
February Natural ventilation
March Natural ventilation
April Natural ventilation
May Natural ventilation
June July Air conditioning/DehumdificationAir conditioning/Dehum
Under floor heating panels
Cross ventilation
Cross ventilation
Cross ventilation
Cross ventilation
AC and Lime plaster
AC and Lime plaster
Humdification
Internal heat gain
Mass cooling
Mass cooling
Natural ventilation
Natural ventilation
Mistifier
Under floor heating panels
Evaporative cooling
Evaporative cooling
Mass cooling and night ventilation Evaporative cooling and passive ventilation
Cross ventilation
Cross ventilation
Increase in clothing
Very slight decrease in clothing and light activity
More decrease in clothing due to slight increase in More decrease clothing due room temp. to increase in temp Reduction of activity levels
Reduction of activity levels
Reduction of activity lev
Air velocity (m/s) Clo value (Clo) Metabolic rate (met) MRT (celsius)
May Natural ventilation
Strategy 1
0.2 1.35 1.3 20
How to achieve ACitand Lime plaster Visuals Strategy 2 Natural ventilation Mass cooling and night ventilation Evaporative cooling and passive How to achieve it ventilation ventilation Cross Visuals
0.2 0.6 0.85 25
0.2 0.85 0.95 25
January February June July August Internal heat gain NaturalNatural ventilation Air conditioning/DehumdificationAir conditioning/Dehumdification ventilation
Cross ventilation
ng due
0.2 1.15 1.3 20
parameters will levels change Reduction of activity levels What are theReduction ofthat activity Air velocity 0.25(m/s) Clo value0.6 (Clo) Metabolic rate (met) 0.55 MRT (celsius) 27
0.25 0.6 0.55 27
0.2 0.6 0.85 25
0.25 0.6 0.55 27
March September OctoberApril Natural ventilation Natural ventilation Natural ventilation Natural ventilation
May November Natural ventilation Natural ventilation
0.25 0.6 0.55 27
July December June Air conditioning/DehumdificationAir conditionin Passive solar heating Use of landscape as AC and Lime plaster AC and Lime p shading device
Under AC and floor Lime heating plaster panels
Cross ventilation Cross ventilation
Cross ventilation Cross ventilation
Cross ventilation Cross ventilation
ventilation Cross Cross ventilation
Humdification Natural ventilation
InternalAir heat gain conditioning
cooling AirMass conditioning
Mass cooling Mass cooling
Mistifier Cross ventilation
Under floor AC heating panels
Evaporative ACEvaporative cooling Evaporative cooling cooling
Mass cooling Natural ventilation Internal heat gain and night ventilation Natural ventilation Evaporative cooling and passive Cross ventilation Underventilation floor heating panels Cross ventilation
Increase inofclothing Reduction activity levels
Very slight decrease Slight increaseinin clothingactivity and light activity
More decrease in clothing Slighter decrease in temp More decrease clothing due due decrese to slight in increase in Slight Slighter decrease in temp and Slighter decrease in temp and and slighter increase in room temp. to increase in temp Reduction Reduction of activity levels temp. slighter increase in temp. slighter increase of in activity temp. levels temp.
0.2 1.35 1.3 20
0.25 0.6 0.55 27
0.250.2 1.15 0.6 0.751.3 2720
0.25 0.7 0.85 25.5
0.2 0.85 0.95 25
0.25 0.2 1.05 0.6 0.85 0.85 23 25
0.25 1.8 0.85 22
0.25 0.6 0.55 27
0.25 2.1 0.85 20.5
OBSERVATION: The top 3 design strategies that can be used are Cross-ventilation, Evaporative cooling and Air conditioners Page No: 3
Table
Mechanical Systems
Page No: 503
Table
Psychrometric Chart
Natural ventila
Cross ventilati
Reduction of a 0.25 0.6 0.55 27
Strategy 1
Internal Heat Gain
Underfloor Heating System
Modern underfloor heating systems use either electrical resistance elements (“electric systems”) or fluid flowing in pipes (“hydronic systems”) to heat the floor. Either type can be installed as the primary, whole-building heating system or as localized floor heating for thermal comfort.
Reference: https://royaltiles.co.uk/product/ambermat-150wm2/ Page No: 4
Strategy 1
Mechanical Systems
Page No: 604
Strategy 1
Psychrometric Chart
Strategy 2
Humidification Mistifier
A humidifier is a device, primarily an electrical appliance, that increases humidity (moisture) in a single room or an entire building. In the home, point-of-use humidifiers are commonly used to humidify a single room, while whole-house or furnace humidifiers, which connect to a home’s HVAC system, provide humidity to the entire house.
Reference: https://www.gofoginc.com/applications/commercial-humidification/ Page No: 5
Strategy 2
Mechanical Systems
Page No: 05 7
Strategy 2
Psychrometric Chart
Strategy 3
Natural Ventilation Cross-Ventilation
Natural cross ventilation is when openings in a certain environment or construction are arranged on opposite or adjacent walls, allowing air to enter and exit. Indicated for buildings in climatic zones with higher temperatures, the system allows constant changes of the air inside the building, renewing it and still, considerably reducing the internal temperature.
Reference: https://nzeb.in/knowledge-centre/passive-design/natural-ventilation/cross-ventilation-2/ Page No: 6
Strategy 3
Mechanical Systems
Page No:06 8
Strategy 3
Psychrometric Chart
Strategy 4
Mass Cooling
Evaporative Cooling
When warm air is passed through water, and then lowering its temperature gives us the evaporative cooling system. To lower the temperature, the water is absorbed by the air in the process. These evaporative cooling procedure provides a large amount of naturally cooled air into your room, and therefore, there is no problem if you keep your windows and doors in the far corner of the room open. Instead, it will take in the hot air, and give you the cool air.
Reference: https://www.vankool.com/blogs/portable-air-cooler-vs-portable-ac/how-evaporative-cooling-works/ Page No: 7
Strategy 4
Mechanical Systems
Page No: 07 9
Strategy 4
Psychrometric Chart
Strategy 5
Night Ventilation Passive Cooling
It is the removal of heat from a building by bringing in cool night air without the use of active HVAC cooling and ventilation. Typically, this is done by leaving windows and openings closed in the day, and opening them up at night to flush warm air out of the building.
Reference: https://knowledge.autodesk.com/search-result/caas/simplecontent/content/night-purge-ventilation.html Page No: 8
08 Page No: 10
Strategy 5
Strategy 5
Mechanical Systems
Psychrometric Chart
Strategy 6
Dehumidification Lime Plaster
The process in which the moisture or water vapor or the humidity is removed from the air keeping its dry bulb (DB) temperature constant is called as the dehumidification process.
Reference: https://mkl-technology.com/en/products/micropore-dehumidifying-plaster/ Page No: 9
Strategy 6
Mechanical Systems
Page No: 11 09
Strategy 6
Psychrometric Chart
REFERENCES: D. (n.d.). PD:March Psychrometric Chart. Drajmarsh.Bitbucket.Io. Retrieved March 20, 2021 R3. (2021, 4). Elevator Types. Archtoolbox. https://drajmarsh.bitbucket.io/psychro-chart2d.html https://www.archtoolbox.com/materials-systems/vertical-circulation/elevatortypes.html Royal Tiles Cardiff is under24). construction. (n.d.). Royaltiles.Co.Uk. Retrieved March 27, 2021 amazon. (2021, February TRANSPORTATION SYSTEM IN BUILDING LIFTS. Slideshare. https://royaltiles.co.uk/product/ambermat-150wm2/ https://www.slideshare.net/NurulAdha2/lift-29150998 GoFog. (n.d.).U.Commercial Humidification FoggersSlideshare. & Humidifiers. Retrieved March 23, 2021 Dhameliya, (2021, February 24). LIFTSSystems, & ESCALATORS. https://www.gofoginc.com/applications/commercial-humidification/ https://www.slideshare.net/MitaliGondaliya/lifts-46213003 cross ventilation. (2020, 22). Fastest-Moving NZEB. Which Building Has the July World’s Elevator? (2020, May 27). Archdaily. https://nzeb.in/knowledge-centre/passive-design/natural-ventilation/cross-ventilation-2/ https://www.archdaily.com/879757/which-building-has-the-worlds-fastest-moving-elevator Luo, V. (2017, November 27). how-evaporative-cooling-works. Vankool | Top Portable Evaporative Cooler Manufacturer in China https://www.vankool.com/blogs/portable-air-cooler-vs-portable-ac/how-evaporative-cooling-works/ Sustainable_Building_Design_LC95QKQ55GPR. (2018, April 27). Night-Purge Ventilation. Search | Autodesk Knowledge Network. https://knowledge.autodesk.com/search-result/caas/simplecontent/content/night-purge-ventilation.html MKL SolidTechnology GmbH. (2021, January 15). MicroPore Dehumidifying plaster ®️. https://mkl-technology.com/en/products/micropore-dehumidifying-plaster/
Page No: 10 Page No: 12 10
References References
Mechanical Systems Psychrometric Chart
02
COOLING SYSTEM
Radiant Cooling System
Outdoor unit
Radiant Cooling System
- Compressor A compressor absorbs gas refrigerant from low pressure side of an evaporator through the pipes and compresses the refrigerant, this increase both temperature and pressure of refrigerant before passing the fluid to condenser. How
Suitable for hot and dry climate and for residential setups. How Does Radiant Cooling Work?. (2016, September 19).
Indoor Unit - Pex Pipes Loops of cross-linked polyethylene pipes are embedded in walls/ floors/ ceiling and chilled water passed through them
Compressor Works in a Cooling System? (2019).
- Condenser The function of the condenser in a refrigeration system is to transfer heat from the refrigerant to another medium, such as air and/or water. Condensers - an overview | ScienceDirect Topics. (2019).
Fairconditioning. (2018, October 30).
- Manifold A manifold is a device connecting water pipes in an underfloor heating and cooling system.
- Evaporator The evaporator removes heat from the area that is to be cooled. The desired temperature of cooling of the area will determine if refrigeration or air conditioning is desired. Evaporators - an overview |
Cubick, R., & Cubick, R. (2018, October 23).
- Water Pump Used to pump the water throughout the system
ScienceDirect Topics. (2019).
-
- Water Storage and Chiller Used to store and cool the fluid medium to required temperature.
The expansion valve removes pressure from the liquid refrigerant to allow expansion or change of state from a liquid to a vapour in the evaporator. Expansion
Fairconditioning. (2018, October 30).
-
Thermostat
Temperature regulating device, placed on the interior wall Thermostats. (2019).
Figure 1: Radiant Cooling Process Page No: 2
Page No: 12 15
Expansion Valve
Psychrometric Chart
Radiant Cooling System
valves - an overview | ScienceDirect Topics. (2019).
Mechanical Systems
Cooling Systems
A radiant cooling system is a temperature-controlled surface that cools indoor temperatures by removing sensible heat and where more than half of heat transfer occurs through thermal radiation. Heat will flow from objects, occupants, equipment and lights in a space to a cooled surface as long as their temperatures are warmer than that of the cooled surface and they are within the line of sight of the cooled surface. The process of radiant exchange has a negligible effect on air temperature, but through the process of convection, the air temperature will be lowered when air comes in contact with the cooled surface. How Does Radiant Cooling Work? -. (2016b, September 19).
Figure 2: PEX piping layout floor section
Figure 3: Radiant Cooling System operating with Air Handling Unit (Prateek Srivastava, 2017)
No: 3 PagePage No: 13
Strategy 1 System Radiant Cooling
Mechanical Systems Cooling Systems
Variable Radiant Flow
Variable Radiant Flow Elements in the system: • Compressor • Condenser • Evaporator • Expansion valve • Controlling Manifold
Variable refrigerant flow (VRF), also known as variable refrigerant volume (VRV), is an HVAC (Heating, Ventilation and Air Conditioning) technology. VRFs use refrigerant as the cooling and heating medium. This refrigerant is conditioned by a single or multiple condensing units (which may be outdoors or indoors, water or air cooled), and is circulated within the building to multiple indoor units.
Working Principle Compressor
Air compressors work by forcing air into a container and pressurizing it. Then, the air is forced through an opening in the tank, where pressure builds up. Think of it like an open balloon: the compressed air can be used as energy as it’s released.
Condenser
Condenser a part of a refrigeration system, is a type of heat exchanger that transforms gas or vapor into a liquid that transfers heat from the tube to the air near the tube in a very rapid manner. It’s an exothermic process, so the condenser temperature is high.
Evaporator
Evaporation is a process that simultaneously heats and Transfers mass resulting into separation of vapour from a solution. Evaporation occurs where molecules obtain enough energy to escape as vapour from a solution. The rate of escape of the surface molecules depends primarily upon the temperature of the liquid, the temperature of the surroundings, the pressure above the liquid, surface area and rate of heat propagation to product.
Expansion Valve
A thermal expansion valve or thermostatic expansion is a component in vapor-compression refrigeration and air conditioning systems that controls the amount of refrigerant released into the evaporator and is intended to regulate the superheat of the refrigerant that flows out of the evaporator to a steady value. Although often described as a "thermostatic" valve, an expansion valve isn't able to regulate the evaporator's temperature to a precise value. The evaporator's temperature will only vary with the evaporating pressure, which will have to be regulated through other means. Reference:
Page No: 4
Page No: 14
Strategy 1
Variable Radiant Flow
Mechanical Systems
Cooling Systems
Fan Coil Systems
Fan Coil Systems Fan coil units are typically found in places where cooling requirements are small or on a room-byroom basis, such as hotel rooms and apartments. Working Principles Of FAN COIL UNITS Fan coil systems use terminal cabinets in each room serviced by 2, 3, or 4 pipes approximately 11/2" each in diameter. A fan blows air over the coils which are serviced by hot or chilled water or air. Each fan coil cabinet can be individually controlled. Four-pipe fan coils can provide both heating and cooling all year long. Most piping is steel. Non-cabinet units may be concealed in closets or custom cabinetry, such as benches, can be built. Air-water systems use the beneficial features from all air and all water systems. The energy is carried in the water and air is used, usually at high velocity, for ventilation.
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Fan Coil System Strategy 1
Cooling Systems Mechanical Systems
Components in the system: Indoor Units: Finned Tube Coils Filter Fan Motor Fan Water Control Valves Coil Connections Return Air Openings Auxillary Condensate Pan
Outdoor Units: - Central Plant
FINNED TUBE COILS Finned-tube coils (sometimes known as heat transfer coils) have two important parts that convey heat transfer. The first is the tubes, which also are called the “primary surface.” The second is the finned surface, which also is known as the “secondary surface.” Both are important to creating the designed heat transfer with balanced air- and water-side resistance. FILTER The primary function of a filter is to keep the components inside the system clean. This is what the basic filters are designed for; as the air travels the ductwork and arrives at the furnace the filter will trap all large debris and particles from the air. The result is air that is cleaner passing through the furnace to be delivered back to the home. AUXILLARY CONDENSATE PAN
These are only used when failure of the main drain pan will damage the house. This is a secondary pan, provided because the primary drain will eventually leak.This pan should be checked for rust, dirt accumulation, blocked drain line, improper slope and poor attachment. Page No: 6
Page No: 16
Strategy 1
Fan Coil System
Mechanical Systems
Cooling Systems
Desiccant Wheel A desiccant wheel is a common type of sorp�on dehumidifier using a solid desiccant. It is also known as a rotary dehumidifier. The desiccant material is coated, impregnated, or formed in place on the suppor�ng rotor structure. The desiccant wheel is called a passive desiccant wheel or enthalpy wheel or rotary energy wheel, when there is no regenera�on air heater. It is called an ac�ve desiccant wheel when it is provided with an air heater and the regenera�on and process air side are separated by clapboard. The wheel is installed with thermal insula�on and air-proof material, so no mass and energy exchange takes place with the surroundings.
Mechanism –
Warm and humid is passed through a damper to regulate flow of air; it is then passed through a filter to filter out the air. The warm air is passed through the rota�ng desiccant wheel. The silica gel present in the desiccant wheel absorbs the moisture in the air and releases hot air with no moisture. The unit heats this air to 90 to 140 degrees Celsius, and these high temperatures drive the moisture out of the silica gel. This hot air is released to cooling coil, which converts the high temperature air to lower temperature with higher moisture content. The cold air is pumped out. The warm air inside the room is passed through a heater, a desiccant wheel to absorb the moisture and the supplied outside the room. The air has to be changed from low temperature range to high temperature to con�nue the humidifica�on process.
Damper outside air
Air pump
F i l t e r
Dw e h s e i e c l c a n t
Cc oo oi l l i n g
Air pump
Damper A damper is a valve or plate that stops or regulates the flow of air inside. Filter A clean air filter is designed to capture dirt and debris from the outside air, preven�ng them from reaching the combus�on chamber and reducing the likelihood of you receiving a large repair bill. Desiccant wheel Desiccant wheels are also known as heat recovery wheels. The main purpose of a desiccant wheel is dehumidifica�on without the use of refrigera�on. A typical packaged air condi�oning system removes humidity from the air by lowering the air temperature below the dew point and allowing moisture to condense onto the fins of the indoor coil. Cooling coil To be more efficient, the cooling coils require flaps that can be of different designs, which fulfill the func�on of trapping the heat and improving the heat exchange between the fluid that is inside the coil and the ambient air Heater An evapora�ve air cooler is atype of air condi�oner that works by harnessing the power of evapora�on to cool air tempertaure. When water evaporates, it turns from liquid to gas .The highest energy par�cless leave the water first,and this leads to a change in temperature ReferenceSec�go RSA Domain Valida�on Secure Server CA. (2020, November 26). Desiccant cooling. Daviddarling.Info. h�ps://www.daviddarling.info/encyclopedia/D/AE_desiccant_cooling.html
Heater
Cloudflare Inc ECC CA - 3. (2020, July 31). Desiccant wheel technology. Brinco. h�ps://www.brinco.com/what-is-desiccant-wheel-technology-in-what-environments-are-they-most-efficient-and-in-what-environments-are-they-least-efficien t-do-they-really-work-well/ Cloudflare Inc ECC CA - 3. (2020, July 21). Desiccant Dehumidifiers And How They Work. Blog.Purennatural. h�ps://blog.purennatural.com/desiccant-dehumidifiers-work
Page No.07 17
Desiccant wheel
Mechanical Systems
Page No: 18
Page No: 8
Split Air Conditioning System
Strategy 1
Reference: https://royaltiles.co.uk/product/ambermat-150wm2/ Cooling Systems
Mechanical Systems
Page No: 19
Page No: 9
Split Air Conditioning System
Strategy 1
Reference: /
Cooling Systems
Mechanical Systems
REFERENCES: How Does Radiant Cooling Work?. (2016, September 19). Retrieved http://www.oorja.in/what-is-radiant-cooling/how-does-radiant-cooling-work/ R3. (2021, March 4). Elevator Types. Archtoolbox.
https://www.archtoolbox.com/materials-systems/vertical-circulation/elevatortypes.html Fairconditioning. (2018, October 30). Radiant Cooling Animation. Retrieved from https://www.youtube.com/watch?v=dYjMBfORftk amazon. (2021, February 24). TRANSPORTATION SYSTEM IN BUILDING LIFTS. Slideshare. Cubick, R., & Cubick, R. (2018, October 23). The Heart of An Effective Underfloor Heating & Cooling Project: The Manifold. Retrieved from https://www.slideshare.net/NurulAdha2/lift-29150998 https://web.uponor.hk/radiant-cooling-blog/the-heartof-an-effective-underfloor-heating-cooling-project-themanifold/#:%7E:text=Manifolds%3A%20 The%20Hub%20of%20Every,underfloor%20heating%20and%20cooling%20system.&text=Uponor%20is%20a%20leading%20international,enerDhameliya, U. (2021, February 24). LIFTS & ESCALATORS. Slideshare. gy%2Defficient%20radiant%20heating%20solutions. https://www.slideshare.net/MitaliGondaliya/lifts-46213003 Thermostats. (2019). Retrieved from Which Building Has the World’s Fastest-Moving Elevator? (2020, May 27). Archdaily. https://www.energy.gov/energysaver/thermostats https://www.archdaily.com/879757/which-building-has-the-worlds-fastest-moving-elevator
How Compressor Works in a Cooling System? (2019). Retrieved from https://www.harn.co.th/en/articles/how-compressor-works-in-a-coolingsystem/#:%7E:text=Compressor%20is%20extremely%20important%20in,passing%20the%20fluid%20to%20condenser. Condensers - an overview | ScienceDirect Topics. (2019). Retrieved from https://www.sciencedirect.com/topics/agricultural-and-biologicalsciences/condensers#:%7E:text=The%20function%20of%20the%20condenser,%2C%20and%20(3)%20evaporative. Evaporators - an overview | ScienceDirect Topics. (2019). Retrieved from https://www.sciencedirect.com/topics/agricultural-and-biologicalsciences/evaporators#:%7E:text=The%20function%20of%20the%20condenser,%2C%20and%20(3)%20evaporative. Prateek Srivastava, Y. K. (2017). ANALYSIS OF RADIANT COOLING SYSTEM INTEGRATED WITH COOLING. Oak Ridge, TN, 37831, USA.: Oak Ridge National Laboratory.
Page No: 10 Page No: 20
References Psychrometric Chart
Mechanical Systems Mechanical Systems
Expansion valves - an overview | ScienceDirect Topics. (2019). Retrieved from https://www.sciencedirect.com/topics/agricultural-and-biologicalsciences/evaporators#:%7E:text=The%20function%20of%20the%20condenser,%2C%20and%20(3)%20evaporative. How Does Radiant Cooling Work? -. (2016b, September 19). Retrieved from http://www.oorja.in/what-is-radiant-cooling/how-does-radiant-coolingwork/#:%7E:text=A%20radiant%20cooling%20system%20is,transfer%20occurs%20through%20thermal%20radiation.&text=Radiant%20cooling%20cools%20a%20floor,the%20rest%20of%20the %20room. A comparative thermodynamic and economic analysis and assessment of a conventional HVAC and a VRF system in a social and cultural center building. (2017, April 1). ScienceDirect. https://www.sciencedirect.com/science/article/abs/pii/S037877881730419X
Condenser Working Principle. (2018, February 5). Changzhou Vrcoolertech Refrigeration Co.,Ltd. https://www.vrcoolertech.com/news/what-is-condenser-working-principle-12276228.html Principles of Evaporators. (n.d.). Www.Jnkvv.Org. Retrieved February 2, 2020, from http://www.jnkvv.org/PDF/15042020094428BASIC%20PRINCIPLES%20OF%20EVAPORATORS.pdf Wikipedia contributors. (2021a, March 22). Thermal expansion valve. Wikipedia. https://en.wikipedia.org/wiki/Thermal_expansion_valve Wikipedia contributors. (2021b, March 29). Variable refrigerant flow. Wikipedia. https://en.wikipedia.org/wiki/Variable_refrigerant_flow Zitzman, L. (2020, January 3). Working of Compressor. Bigrentz.Com. https://www.bigrentz.com/blog/how-air-compressorswork#:~:text=Air%20compressors%20work%20by%20forcing,as%20energy%20as%20it’s%20released
Page No: 21
Psychrometric Chart
Mechanical Systems
03
HVAC LINE DRAWING
Page No: 23
Variable Refrigerant Flow & Radiant Cooling
HVAC Systems Line Diagram
04
LIFTS AND E L E VAT O R S
LIFTS & ELEVATORS:
Hyraulic Lift
Electric Lift
Common type used today. Use electric lift cable to lift the elevator car with the weight and movement is the catalyst action. Use the traction with the motor. Used in most building > 60ft. Motor room on top of lift shaft will increase the load of building structure. Possibility of noise structure Need a lift wells and maintenance room near the engine room. Traction elevator motor
Page No: 2 Page No: 25
Common type used today. Use electric lift cable to lift the elevator car with the weight and movement is the catalyst action. Use the traction with the motor. Used in most building > 60ft. Motor room on top of lift shaft will increase the load of building structure. Possibility of noise structure Need a lift wells and maintenance room near the engine room. Traction elevator motor
Lifts & Elevators Lifts & Elevators
Mechanical Systems Lifts & Escalator systems
Handicapped Lift
Paternoster
For people with disability who use wheelchair. Or with disabilities who are unable to use ordinary crowded lift of fast services. Mounted on the stair parallel to the ladder FIRE LIFT. Buildings over than 60ft high are required to provide fire lift. This lift controlled by a system back on in emergencies.
A lift systems moves continuously in one direction by providing the same car lifts. Provides the movement up and down continuously. No doors and passengers are forced into or out of the moving car lift Speed – 80 min. Suitable for 6 – 7 storey buildings Not suitable to used by children or older people.
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Lifts & Elevators Lifts & Elevators
Mechanical Systems Lifts & Escalator systems
Double Decker Lift
Machine-Room-Less Elevators
Machine - Room - Less Elevators are traction elevators that do
not have a dedicated machine room above the elevator shaft. The machine sits in the override space and is accessed from the top of the elevator cab when maintenance or repairs are required. The control boxes are located in a control room that is adjacent to the elevator shaft on the highest landing and within around 150 feet of the machine.
Carry passengers without raising double the lift shaft. Have two platforms which are increased. High transport capacity and reduce floor space Number of stops can reduced to 50% - reducing waiting time and shorter car lift trips. Can be used in building which has a same height in every level. The main lobby has two levels. Must have clear indication of the use in the main lobby to avoid confusion.
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Lifts & Elevators Lifts & Elevators
Mechanical Systems Lifts & Escalator systems
Hydraulic Elevators
Geared traction elevators
Hydraulic elevators are support-
ed by a piston at the bottom of the elevator that pushes the elevator up as an electric motor forces oil or another hydraulic fluid into the piston. The elevator descends as a valve releases the fluid from the piston.
Geared traction elevators are
middle of the road in terms of initial cost, ongoing maintenance costs, and energy consumption. Gear-less traction elevators have a high initial cost, medium ongoing maintenance costs, and use energy a bit more efficiently than geared traction elevators.
3 types of geared elevator: Traction elevators
3 types of hydraulic elevator: Conventional Hydraulic Elevators
Geared Traction Elevators Gear-less Traction Elevators
Hole-less Hydraulic Elevators Roped Hydraulic Elevators
Page No: 5 Page No: 28
Lifts & Elevators Lifts & Elevators
Mechanical Systems Lifts & Escalator systems
LIFT SUB SYSTEM :
Lift Shaft
Control motion :
Constructed with reinforced concrete.
Control system :
Size of lift shaft space is determined by the number of user.
includes motor, gear, engines, brakes and power supply
To accommodate the loading and fire resistance.
to get control of lift movements. Door control :
Contained motor connecting lift car platforms, gates and door safety devices.
Safety control :
Contain the safety gear, speed controller for the first balance, heat and lack of power.
Lift Car
Platform where passengers or goods is transported.
Constructed with steel or iron attached with steel frame.
Governor Usually placed at the top of lift shaft.
Fire resistance Elevator hoist ropes on top of a lift car
Placed in room equipped with a lifting beam for maintenance
Equipment to be provided – door, floor
purposes.
panel indicators, button of request,
Have electric motor, safety gear, guard rail, diaphragm mo-
phone, emergency button, lighting,
tion and gear.
ventilation and enough emergency supplies.
Divided into 2 types :
- Closed Lift (typical type)
- Open Lift (bubble type) Open Lift (bubble type) Closed Lift (typical type)
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Lift Sub-systems List Sub-systems
Mechanical Systems Lifts & Escalator systems
Lift Door
Buffer
Lift car is equipped with its own door (sliding type).
To absorb the impact of the lift car when it fell.
Security measure – resist the movement as long as the door
Placed in a room called the lift pit.
is still open
Self closing within a certain time frame. 2 types of sliding door :
Opened automatically when the lift stops at every level.
Swing door – will open when the lift stopped at the lobby.
Counterweight Load borne by the generator is balanced by the counterweight.
Guard Rail
Connected with a wire rope of the elevator car.
Work to keep the car and the counterweight.
Mounted on both sides of the lift shaft which is attached to the wheel of the car.
A safety device to hold the lift from crashing down if the rope break.
Function of counterweight : - To grip the lift car
- Reduce the power of generator
- Reduce the brake to stop the car lifts.
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Lift Sub-systems List Sub-systems
Mechanical Systems Lifts & Escalator systems
ELEVATOR SPEEDS
The fastest installed elevator reaches speeds of 67 feet per second (20.5 meters per second), or 46 miles per hour (73.8 kilometers per hour) in the Shanghai Tower. Not only does the Gensler-designed Shanghai Tower boast the fastest elevator, but also the longest continuous run of 1,898 feet of the 2,073-foot tower (578.5 of 632 meters), as revealed in a recent study by the Council on Tall Buildings and Urban Habitat (CTBUH). At these speeds, you can reach the 119th floor in 55 seconds.
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Elevator Speeds Elevator Speeds
Mechanical Systems Lifts & Escalator systems
WORKING OF ESCALATOR
The core of an escalator is a pair of chains, looped around two pairs of gears & an electric motor runs it.
The motor and chain system are housed inside the truss, a metal structure extending between two floors. As the chains move, the steps always stay level.
At the top and bottom of the escalator, the steps collapse on each other, creating a flat platform. This makes it easier to get on and off the escalator.
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Working of Escalator Working of Escalator
Mechanical Systems Mechanical Systems
REFERENCES: R3. (2021, March 4). Elevator Types. Archtoolbox. https://www.archtoolbox.com/materials-systems/vertical-circulation/elevatortypes.html amazon. (2021, February 24). TRANSPORTATION SYSTEM IN BUILDING LIFTS. Slideshare. https://www.slideshare.net/NurulAdha2/lift-29150998 Dhameliya, U. (2021, February 24). LIFTS & ESCALATORS. Slideshare. https://www.slideshare.net/MitaliGondaliya/lifts-46213003 Which Building Has the World’s Fastest-Moving Elevator? (2020, May 27). Archdaily. https://www.archdaily.com/879757/which-building-has-the-worlds-fastest-moving-elevator
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References References
Mechanical Systems Lifts & Escalator systems
05
QUESTIONAIRS
Ans: COP =
Principles of Mechanical Systems
10. what is EER?
=
Heat absorbed Heat rejected−Heat absorbed
=
Ans: A Carnot cycle is defined as an ideal reversible closed thermodynamic cycle in which there are four successive operations involved, which are isothermal expansion, adiabatic expansion, isothermal compression and adiabatic compression.
2. What is specific heat of water?
11. What is SEER? Ans: Seasonal Energy Efficient Ratio
12. what is MERV? Ans: Minimum Efficiency Reporting Value, commonly known as MERV, is a measurement scale by the ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) to report the effectiveness of air filters
Ans: 4.186 Joules/gram
3. What does the psychrometric chart consist of?
13. what is sensible heat?
Ans:
Ans: Sensible heat is heat exchanged by a body or thermodynamic system in which the exchange of heat changes the temperature of the body or system
DBT (degrees Celsius/ degrees Fahrenheit) WBT (degrees Celsius/ degrees Fahrenheit) Relative Humidity Specific Volume (m3/Kgda) Dew Point (degrees Celsius/ degrees Fahrenheit) Enthalpy (KJ/Kgda) Humidity Ratio (g/Kgda)
14. what is latent heat? Ans: the heat required to convert a solid into a liquid or vapor, or a liquid into a vapor, without change of temperature. E.g.: human beings’ metabolism
15. what is heat load?
4.What is psychrometric chart? Ans: Psychrometric charts are complex graphs that can be used to assess the physical and thermodynamic properties of gas-vapor mixtures at a constant pressure. They are often used to assess the properties of moist air. This can be useful in the design of heating, ventilation and air-conditioning systems for buildings
5.What is sensible heating? Ans: A psychrometric process that involves the increase or decrease in the temperature of air without changing its humidity ratio.
6. what is heating and humidifying?
Ans: The heating load is the amount of heat energy that would need to be added to a space to maintain the temperature in an acceptable range.
16. what is cooling load? Ans: The cooling load is the amount of heat energy that would need to be removed from a space (cooling) to maintain the temperature in an acceptable range.
17.what is SHF (Sensible Heat Factor)? Ans:
RSH
SHF = (SH+LH) =
SH TH
Where, SHF – sensible heat factor SH – sensible Heat
Ans: A psychrometric process that involves the simultaneous increase in both the dry bulb temperature and humidity ratio of the air
LH – latent heat
7. what is cooling and dehumidifying?
TH – total heat
Ans: A psychrometric process that involves the removal of water from the air as the air temperature falls below the dewpoint temperature.
18.what is RSHF (Room Sensible Heat Factor)?
8. what is Adiabatic or evaporative cooling?
Ans:
Ans: A psychrometric process that involves the cooling of air without heat loss or gain. Sensible heat lost by the air is converted to latent heat in the added water vapor.
9. What is COP (coefficient of performance)? Cooling effect
effect Ans: COP = Cooling = Work Input
10. what is EER?
Ans: Energy Efficient Ratio
Page No: 35
11. What is SEER?
Heat absorbed Heat rejected−Heat absorbed
Tc−Th Tc
Ans: Energy Efficient Ratio
1. What is Carnot cycle?
• • • • • • •
Cooling effect Work Input
RSH
RSHF = (RSH+RLH) =
RSH RTH
Where, RSHF – room sensible heat factor RSH – room sensible Heat RLH – room latent heat
Tc−Th
= Tc−Th Tc
RTH – room total heat
19.what is ERSHF (Effective Room Sensible Heat Factor)? Ans:
ERSH
ERSHF = (ERSH+ERLH) =
Principles of Mechanical Systems
ERSH ERTH
Where, ERSHF – Effective room sensible heat factor
Questionnaire
RLH – room latent heat
• •
RTH – room total heat
25. What is Space Cooling load?
19.what is ERSHF (Effective Room Sensible Heat Factor)? Ans:
ERSH
ERSHF = (ERSH+ERLH) =
Wind speed, sky clearness, ground reflectance etc. Design outdoor conditions data can be found in ASHRAE Fundamentals Handbook
Ans: The rate at which heat must be removed from a space to maintain air temperature and humidity at the design values. Cooling load differs from the heat gain due to
ERSH ERTH
Where, ERSHF – Effective room sensible heat factor
• •
ERSH –Effective room sensible Heat
delay effect of conversion of radiation energy to heat Thermal storage lag
ERLH – Effectiveroom latent heat
26. What are the cooling load components?
ERTH – Effectiveroom total heat
Ans:
20.What is BTU (British Thermal Unit)? Ans: A BTU is the amount of heat needed to raise 1 (one) pound of water by 1(one) degree Fahrenheit
21.What is the formula SEER (Seasonal Energy Efficiency Ratio)? Ans: SEER =
Output cooling energy in BTU over a season input cooling energy in WH during the same season
22. what is the purpose of load estimate?
Ans: Bypass factor is an important coil characteristic on moisture removal performance.
Load profile over a day Peak load (basis for equipment sizing) Operation Energy analysis HVAC Construction cost
Its value depends on: • Number of rows/fins per inch
23. what are the principles of cooling load estimate? 23. what are the principles of cooling load estimate? Ans: Ans: • • • • • • • • • • • • • • • • • • • •
• Velocity of air
28. What is the equation for EER?
Enclosure heat transfer characteristics Enclosure heat transfer characteristics Conduction Conduction Convection Convection radiation radiation Design conditions Design conditions Outdoor & indoor Outdoor & indoor Heat Gains Heat Gains Internal Internal External or Solar External or Solar Thermal capacity Thermal capacity
Ans:
Indoor air quality Indoor air quality Air contaminants Air contaminants Air cleaning Air cleaning Acoustic requirements Acoustic requirements Pressurization requirements Pressurization requirements Weather data required for load calculation Weather data required for load calculation Temperature & humidity Temperature & humidity Wind speed, sky clearness, ground reflectance etc. Wind speed, sky clearness, ground reflectance etc. Design outdoor conditions data can be found in ASHRAE Fundamentals Handbook Design outdoor conditions data can be found in ASHRAE Fundamentals Handbook
25.Page What Space Cooling load? No:is 25. What is36Space Cooling load?
Output cooling energy in BTU Input electrical energy in W
29. What are different types of external loads? Ans: • • •
24. Conditions required for indoor design? 24. Conditions required for indoor design? Ans: Ans: • • • • • • • • • • • • • • • • • •
Space cooling load Sizing of supply air flow rate, ducts, terminals and diffusers It is a component of coil load Bypassed infiltration is a space cooling load Cooling coil load Sizing of cooling coil and refrigeration system Ventilation load is a coil load
27. Define bypass factor?
Ans: • • • •
• • • • • • •
Heat gains from Walls and roofs Solar gains through fenestrations Outdoor air
30. What are different types of internal loads? Ans: • • •
People Appliances Lights
Principles of Mechanical Systems
Ans: The rate at which heat must be removed from a space to maintain air temperature and humidity at Ans: The rate at which heat must be removed from a space to maintain air temperature and humidity at the design values. Cooling load differs from the heat gain due to
Questionnaire
Lifts and Escalators
6. What are the factors affecting selection of lift?
1. Define Lift/Elevator
Ans: •
Ans: Vertical transport equipment that efficiently moves people between floors (levels, decks) of a building, vessel or any other structure. Generally, powered by an electric motor that drive by a traction cable and counterweight systems like a hoist or hydraulic pump.
2. What are the types of lifts based on their use? Ans: • • • • •
Trade LiftHospital Lift Car Lifts High Residential Lift Fire lift
3. What are the types of lifts based on their function?
• •
7. Define Escalators Ans: Escalators are moving stairs-a conveyor transport device where the treads move on a track at an incline or decline to transport people from one floor to another. These may not be used as a means of egress. The typical speed of an escalator is 100 feet per minute.
8. What Are the types of Escalators? Ans: • • •
Ans: • • • •
Electric Lift Hydraulic Lift Pneumatic Lift Paternoster Lift
Ans: • • • • • • • • •
Ans: Lift Car Lift Door Governor Lift Shaft Guard Rail Counterweight Buffer
5. What are the factors involved in designing a lift?
Ans: • • •
Population or the no. of people who require lift service. Handling Capacity or the maximum flow rate required by these people. Quality of Service required or interval.
Page No: 37
Angle of inclination Balustrade Handrails Treads/Steps Landings Comb plates Trusses/Girders Tracks System Rated Load
10. What are the advantages of Escalators?
Ans: • • •
Parallel type Multi-parallel type Criss-cross type
9. What are the design requirements of an Escalator?
4. What are the different components of Lifts?
• • • • • • •
Utility - The function must be identified whether lift is for residential, commercial, or hospital etc. Capacity - This depends on type of building and frequency of access to lift. Speed - This depends on no. of stops and users.
Lifts & Escalators
It has more loading capacity and allows large no of people to move from one place to another at the same time. It is more efficient as people don’t have to wait as in case of elevator. Its speed can be adjusted as per crowd management and can be turned off when not in use.
Questionnaire
HVAC Systems
8) What are the basic components in HVAC system? Ans:
1) What is HVAC?
• • • • • • • • • • • •
Ans: HVAC stands for Heating, Ventilation, and Air Conditioning. HVAC refers to the different systems used for moving air between indoor and outdoor areas, along with heating and cooling of buildings.
2) What is VRF? Ans: Variable refrigerant flow (VRF), also known as variable refrigerant volume (VRV) is an HVAC technology which uses refrigerant as the cooling and heating medium.
3) What is AHU? Ans: An air handling unit (AHU), is a device used to regulate and circulate air as part of a heating, ventilating, and air-conditioning (HVAC) system.
4) What is a condenser? Ans: a condenser is a heat exchanger used to condense a gaseous substance into a liquid state through cooling.
9)
What is split AC?
10)
What are refrigerant?
Ans: The split systems contain two central devices the condenser, located outdoor, and the evaporator, located indoors. The split systems can contain one condenser unit and connected to multiple evaporator units to serve multiple zones as possible under same conditions or different environmental conditions.
Ans: A substance used to absorb and transport heat for the purpose of cooling.
5) What is a compressor? Ans: The compressor is responsible for moving the refrigerant between the evaporator and condenser coils, ensuring that the refrigerant changes to gas or liquid as needed.
11)
What is cooling tower?
Ans: cooling tower A device used to reject the heat from a water-cooled condenser by spraying the condensing water over fill while drawing outdoor air upward through the slats.
6) What is a desiccant dehumidifier? Ans: A desiccant dehumidifier uses chemical attraction instead of condensation to remove moisture from the air. The most important piece of machinery in one of these units is the desiccant wheel. The desiccant wheel is a sort of honeycomb network of small airways lined with silica gel.
12)
Ans:
7) what is a fan coil unit? Ans: A fan coil unit (FCU) contains a fan which draws the air in a space into the unit then blows it over a cooling or heating coil. The air comes out of the FCU either cooler or hotter than before. They are used in some office buildings and shopping centers and typically specified where there are multiple small spaces requiring individual control.
Page No: 38
Air filter Supply fan Exhaust and an air outlet Outdoor air intake Ducts Return air system Heating and cooling coils Self-contained heating or cooling unit Cooling tower Boiler Control Water chiller
HVAC Systems
What are the components of split Ac? • • • • •
Refrigerant Compressor Condenser coil Expansion Valve Evaporator coil
Questionnaire
13)
Ans:
Difference between Window A/C and Split A/C.
Window A/C Heat exchangers, compressors, motor and connecting pipes are placed on the same base Occupies more space than split AC Installation is easy Multiple cooling units not possible Cheaper than the split AC for the same tonnage More noise (air) than split AC Easy serviceability Max. capacity is 2.0 ton
14)
Split A/C It consists of 2 units – indoor unit and outdoor unit Occupies less space Installation not as easy as window AC Multiple cooling units possible Costlier than window AC for same tonnage Less noise compared to window AC Difficult for service Capacity not restricted to 2.0 ton
List Components for radiant cooling.
Ans: • • • • • •
15)
Pex pipes Water pumps Thermostat Manifold Chiller Water storage tank
18)
What is a chiller?
Ans: A chiller is a machine that removes heat from a liquid via a vapor-compression, adsorption refrigeration, or absorption refrigeration cycles. This liquid can then be circulated through a heat exchanger to cool equipment, or another process stream (such as air or process water).
19)
What is an Expansion Valve?
Ans: A thermal expansion valve or thermostatic expansion valve is a component in vapor-compression refrigeration and air conditioning systems that controls the amount of refrigerant released into the evaporator and is intended to regulate the superheat of the refrigerant that flows out of the evaporator to a steady value.
20)
What is an evaporator?
Ans: in air conditioner’s evaporator coil, also called the evaporator core, is the part of the system where the refrigerant absorbs heat. That is, it’s where the cold air comes from. The evaporator coil is located inside or near the air handler where the blower fan is. Evaporator coils are made from copper, steel, or aluminum because these metals conduct heat easily.
----------------------------------------------------------------------X----------------------------------------------------------------------
Which climate radiant cooling is mainly used for?
Ans: hot and humid
16)
What is manifold, why is it used in radiant cooling?
Ans: It is chamber branching into several openings (primarily used in radiant cooling for distribution of chilled water in different rooms simultaneously)
17)
What is thermostat?
Ans: device to detect temperature changes and maintaining the temperature of the room.
Page No: 39
HVAC Systems
Questionnaire
Mechanical System