Your SlideShare is downloading. ×
Experimental performance analysis of flow of air curtain
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

Experimental performance analysis of flow of air curtain

104
views

Published on

Published in: Technology, Business

0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
104
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
0
Comments
0
Likes
0
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide

Transcript

  • 1. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 –6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 3, May - June (2013) © IAEME79EXPERIMENTAL PERFORMANCE ANALYSIS OF FLOW OF AIRCURTAINMr Nitin Kardekar1, Dr. V K Bhojwani2, Dr Sane N K31Principal, Jayawantrao Sawant Polytechnic.Research Scholar, Singhania University2Professor JSPM’s Jayawantrao Sawant College of Engineering, Pune3Research Supervisor, Singhania UniversityABSTRACTA study is undertaken to establish a relation between the power consumed by aircurtain and the performance of air curtain in terms of discharge air velocity from it. Theprototype experimental set up is established in the laboratory. The series of observations aremade by varying the input voltage and its effect on the output air velocity of the air curtain.The air velocity forms the invisible barrier of air in the form of curtain which separates theconditioned and unconditioned environments. The results are displayed in the form of graph.The graphs are analysed in the light of actual performance and conclusions are drawn fromthe study. The study reveals that there is great scope of savings in power consumption bymaking small changes in the design of air curtain.Keywords: air curtain, discharge air velocity, performance of air curtain, power consumptionof air curtain, effectiveness of air curtain.INTRODUCTIONFor the study and analysis of the performance of air curtain, the application chosen isdoor way air curtain. The door way air curtains are extensively used in shopping malls,banks, retail shop etc. The purpose is to restrict the cold/hot air loss from conditioned spaceby installing the air barrier. An air curtain device also helps in prevention of dust, dirt orinsects entering in to conditioned spaces. Air curtains are also finding applications inavoiding smoke propagation, biological controls and explosive detection portals. Accordingto research by US department of energy, 1875MW energy will be saved per year if supermarket display cabinet air curtain will be operated at optimised performance [4] In 2002 theINTERNATIONAL JOURNAL OF MECHANICAL ENGINEERINGAND TECHNOLOGY (IJMET)ISSN 0976 – 6340 (Print)ISSN 0976 – 6359 (Online)Volume 4, Issue 3, May - June (2013), pp. 79-84© IAEME: www.iaeme.com/ijmet.aspJournal Impact Factor (2013): 5.7731 (Calculated by GISI)www.jifactor.comIJMET© I A E M E
  • 2. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 –6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 3, May - June (2013) © IAEME80UK food and drinks industry used equivalent of 285 tonnes of oil to power its refrigerationindustry, with most being used in cold storage. In developing countries like India; the rise incold storages, super markets, retail stores, banks are not only limited to mega cities but theyhave also become the integral part of suburban’s and small towns. The effects ofglobalisation are inevitable. The air curtains are no more luxury but are the necessary part ofbusiness development and economy. Hence the study of air curtain with respect to Indianclimate is utmost necessary to ensure optimised performance of air curtains which will lead toenergy conservation. The saving of energy (Electrical energy) will always be boon for energystarving country like India.METHODOLOGYThe Technocrat make air curtain for door size W – 950 mm X H – 2530 mm Model 3ft. HV+ Beta is chosen for the analysis purpose. As shown in Figure 1 the prototype of doorway is manufactured with help of plywood which is supported by MS angle frame. The aircurtain is mounted on the door way. The flow straightener is added in order to reduce theturbulences in the air flow. In order to reduce direct interference of the suction head of the aircurtain, the suction duct is added as shown in Figure 1. The length of the Suction head is kept1000 mm from the end of the air curtain device. The power cord of air curtain is connected tomains through the dimmer stat. Dimmer stat helps in the variation of input voltage to the aircurtain device. The voltage change will change the output of dual motor (i.e. speed of theshaft). This results in variations of output air velocity of air curtain device. The air velocity inair curtains is a very important parameter impacting its effectiveness. The input voltage to fanmotor is measured by digital multi meter. The power supplied to air curtain is measured bythe watt meter. In order to measure the air velocity at fixed points, a grid of the thread isplaced in air flow path of air curtain. This facilitates to measure the velocity of air flow of aircurtain when input parameters are varied. With help of grid it is easy to find the location ofpoint in the space for measurement of velocity at different input voltages. The input voltage isvaried from 125 V to 225 V with increment of 25 Volts. The speed of the fan is measuredusing digital Tachometer and the velocity is measured using digital anemometer. All theinstruments are calibrated before use. The entire experimentation is carried out at isothermalconditions; ambient air at 240C ( + 10C) at one atmosphere.RESULT AND DISCUSSIONThe prototype experimental set up is established in the laboratory. The series ofexperimentation is carried out in the laboratory. In the observation, the input voltage therebypower to air curtain is varied and its effect on discharge air velocity of air curtain is observed.The voltage is varied in the steps of 25V with the help of dimmer stat. The speed of thecentrifugal fan of the air curtain is measured with tachometer. The discharge air velocity ismeasured with the help of turbine type anemometer in m/s. The observations and results arepresented graphically. Figure 2 shows the graph of Input voltage verses the power input to aircurtain. Figure 3 shows the graph of Input voltage verses speed of the centrifugal fan of aircurtain motor. Figure 4 shows the graph of Input voltage verses discharge air velocity of theair curtain. From figure 2 it is clear that, as input voltage is increased, the input power alsoincreases. At 125V input the input power observed is 50 watts where as at input voltage 225V it increases to 100 watts. At input of 175 V the input power recorded is 70 watts and at
  • 3. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 09766340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 3, Mayinput voltage of 200 V the input power is 90 watts.air curtain is increased the power consumed by the motor is also found increasing. Figure 3shows the graph of input voltage verses theinput voltage increases the fan speed is also increasethe fan speed is 822 rpm. It reaches to 1432 rpmvolts fan speed stabilises even for ivoltages of 200 V and 225 V the fan speed is 1460 rpm and 1468 rpm respectively.even though there are increments of 25 V and 50Vare only 28 rpm and 36 rpm. The graph of outputvelocity of 3.3 m/s and 5.2 m/s is measured at input voltage of 125V and 150 V. It increasesto 9.2 m/s at input voltage 175 V. A marginal increment of 0.4 m/s and 0.6 m/s is observedfor the further increment in the input voltage of 25 V and 50 V respectively. Thus outputvelocity stabilises beyond 175 V.velocity of the air curtain reveals all these detailsshould run the air curtain near optimum voltage tocan be used, without affecting the performance of air curtainform barrier of moving air to separate the two environments.out of the air curtain device decides the quality of barrier. Higher the velocity, more robust isthe air curtain barrier. From abothe discharge air velocity when it is operated at 175 V, 200 V and 225 V. Thus we can saythat equally strong air curtain can be obtained whenvoltage of 175 V. The furthersubstantial improvement in the dischargeFigure 1International Journal of Mechanical Engineering and Technology (IJMET), ISSN 09766359(Online) Volume 4, Issue 3, May - June (2013) © IAEME81nput voltage of 200 V the input power is 90 watts. Thus as input voltage to fan motor of theair curtain is increased the power consumed by the motor is also found increasing. Figure 3graph of input voltage verses the speed of the centrifugal fan. It is observed thatthe fan speed is also increases initially. For the input voltage of 125 Vthe fan speed is 822 rpm. It reaches to 1432 rpm for the input voltage of 175 V. Beyond 175stabilises even for increased input power to air curtain device.V and 225 V the fan speed is 1460 rpm and 1468 rpm respectively.though there are increments of 25 V and 50V in input voltage, the fan speed incrementsThe graph of output air velocity also shows similar nature. Thevelocity of 3.3 m/s and 5.2 m/s is measured at input voltage of 125V and 150 V. It increasesto 9.2 m/s at input voltage 175 V. A marginal increment of 0.4 m/s and 0.6 m/s is observedfor the further increment in the input voltage of 25 V and 50 V respectively. Thus output175 V. Figure 4 is the graph of input voltage verses the output airreveals all these details. It is clear from above discussionshould run the air curtain near optimum voltage to save the power else the lower power motorbe used, without affecting the performance of air curtain. The air curtains are provided toform barrier of moving air to separate the two environments. The velocity of the air comingdecides the quality of barrier. Higher the velocity, more robust isthe air curtain barrier. From above discussion it is clear that there is not much difference inair velocity when it is operated at 175 V, 200 V and 225 V. Thus we can saythat equally strong air curtain can be obtained when the device is operated even atf 175 V. The further increase in input of power will merely be wastedischarge air velocity.Figure 1: Photo of the Experimental set upInternational Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 –June (2013) © IAEMEThus as input voltage to fan motor of theair curtain is increased the power consumed by the motor is also found increasing. Figure 3It is observed that, asinitially. For the input voltage of 125 Vfor the input voltage of 175 V. Beyond 175For the inputV and 225 V the fan speed is 1460 rpm and 1468 rpm respectively. Thusthe fan speed incrementsshows similar nature. Thevelocity of 3.3 m/s and 5.2 m/s is measured at input voltage of 125V and 150 V. It increasesto 9.2 m/s at input voltage 175 V. A marginal increment of 0.4 m/s and 0.6 m/s is observedfor the further increment in the input voltage of 25 V and 50 V respectively. Thus output airis the graph of input voltage verses the output airfrom above discussion that onesave the power else the lower power motorThe air curtains are provided toThe velocity of the air comingdecides the quality of barrier. Higher the velocity, more robust isve discussion it is clear that there is not much difference inair velocity when it is operated at 175 V, 200 V and 225 V. Thus we can sayevice is operated even at the inputwaste without
  • 4. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 –6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 3, May - June (2013) © IAEME82Figure 2: Input Voltage Vs PowerFigure 3: Input Voltage Vs Fan Speed
  • 5. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 –6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 3, May - June (2013) © IAEME83Figure 4: Input Voltage Vs air Velocity.The optimum voltage there by optimum performance for this model is found to be at175 V. During experimentation it was observed that the power required by the air curtaindevice increases with increase in voltage. The power required at 175 V is 80 watts. At 200 Vand 225 V power consumed is 90 watt (12.5% more) and 100 watt (25% more) respectively.But there is hardly any improvement observed in terms of air velocity (2% and 4%respectively). Hence it is recommended to use lower capacity motor without affecting theperformance of the air curtain device. As discussed earlier the air curtain devices areextensively used across the globe to protect the conditioned environment. The millions of aircurtain are functioning at the malls, banks, commercial places, cold storages etc. If aircurtains devices are shifted to use lower capacity motors at optimised conditions as discussedin the paper without affecting their performance then the huge electrical power will be saved.Using lower power consumption motor for air curtain applications will certainly reduce thedemand of the electricity in larger extents for these commercial spaces.CONCLUSIONThe output of the air curtain device is measured in terms of velocity of air. The inputpower is varied and efforts are made to optimise the performance of the air curtain device. Itis concluded that instead of adopting the generalised approach for designing and installationof air curtain device, it is necessary to design the air curtain device considering the particularapplication. This will ensure the use of the lower capacity and lower power consumptionmotor for air curtain devices for a given application. Considering the extensive use of the aircurtain devices in the entire world the demand of the electricity will be certainly reduce in thelarger extents. And thus millions of dollar will be saved in energy bills globally.024681012100 125 150 175 200 225 250Maximumvelocityinm/sInput voltage to fan motorInput voltage vs discharge air velocity
  • 6. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 –6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 3, May - June (2013) © IAEME84REFERENCES[1] Tassou, S. A. and Pappas T. C., ‘Numerical Investigations into the Performance ofDoorway Vertical Air Curtains in Air-Conditioned Spaces’, ASHRAE Transactions,Vol. 109, No. 1, 2003, pp. 273–279.[2] Y. T, Ge, and S A Tassou,’Simulation of the performance of single jet air curtain forvertical display cabinets’, Applied Thermal Engineering, Vol. 21,2001 pp.201-219.[3] Field B. & Loth, E., ‘Entrainment of refrigerated air curtains down a wall’,Experimental Thermal and Fluid Science, 30, 2006, pp. 175-184,.[4] Dr. Homayun K. Nawaz, Dr. Dana Dabiri Mazyar Amin and Ramin Faramarzi ‘Past,Present and future Research towards air curtain performance optimisation’, OR-05-16-4.[5] Hampl, V., Johnston, O. E. and Murdock, D. J., Jr, ‘Application of an Air Curtain-Exhaust System at a Milling Process,’ American Industrial Hygiene AssociationJournal, Vol. 49, No. 4, 1988, pp. 167–175.[6] Etkin, B. and McKinney, W. D., ‘An Air-Curtain Fume Cabinet’, AmericanIndustrial Hygiene Association Journal, Vol. 53, No. 10, 1992 pp. 625–631[7] A. Aubert and C. Solliec, ‘Push-Pull Air Curtain Performances for VOCsContainment in an Vol 4, No.1 2011, pp.43-50, (ISSN 1735-3645)[8] Mr Nitin Kardekar and Dr Sane N K, ‘Effect of humanoid shaped obstacle on thevelocity profiles of flow of air curtain’ International Journal of MechanicalEngineering and Technology, Volume 3, Issue 3, 2012, pp. 511-516, ISSN Print:0976 – 6340, ISSN Online: 0976 – 6359[9] Kapil Chopra, Dinesh Jain, Tushar Chandana and Anil Sharma, “Evaluation ofExisting Cooling Systems for Reducing Cooling Power Consumption”, InternationalJournal of Mechanical Engineering & Technology (IJMET), Volume 3, Issue 2, 2012,pp. 210 - 216, ISSN Print: 0976 – 6340, ISSN Online: 0976 – 6359.