Performance Evaluation of a Mechanical Draft Cross Flow Cooling Towers Employed in a Subtropical Region

  • Palanisamy Muthukumar
  • Bukke Kiran Naik
  • Amarendra Goswami
Original Contribution
  • 6 Downloads

Abstract

Mechanical draft cross flow cooling towers are generally used in a large-scale water cooled condenser based air-conditioning plants for removing heat from warm water which comes out from the condensing unit. During this process considerable amount of water in the form of drift (droplets) and evaporation is carried away along with the circulated air. In this paper, the performance evaluation of a standard cross flow induced draft cooling tower in terms of water loss, range, approach and cooling tower efficiency are presented. Extensive experimental studies have been carried out in three cooling towers employed in a water cooled condenser based 1200 TR A/C plant over a period of time. Daily variation of average water loss and cooling tower performance parameters have been reported for some selected days. The reported average water loss from three cooling towers is 4080 l/h and the estimated average water loss per TR per h is about 3.1 l at an average relative humidity (RH) of 83%. The water loss during peak hours (2 pm) is about 3.4 l/h-TR corresponding to 88% of RH and the corresponding efficiency of cooling towers varied between 25% and 45%.

Keywords

Water cooled condenser Cross-flow cooling tower Efficiency Water loss 

Notations

A/C

Air conditioning

TR

Ton of refrigeration

RH

Relative humidity

TWL

Theoretical water loss

OTWL

Overall theoretical water loss

AWL

Actual water loss

Special Symbols

ω

Specific humidity, kg/kg of dry air

\({\dot{\text{m}}}\)

Mass flow rate, l/s

∆T

Temperature difference, °C

η

Efficiency, %

Subscript

Win

Hot water inlet

Wout

Cold water outlet

WBT

Wet bulb temperature

DBT

Dry bulb temperature

v

Water vapour

W

Chilled water

Notes

Acknowledgement

The authors express their sincere thanks to IIT Guwahati, Sterling and Wilson Company private Limited, Kolkata Branch and Trane Company private limited, Kolkata Branch for providing the necessary technical support during the experiment.

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Copyright information

© The Institution of Engineers (India) 2018

Authors and Affiliations

  • Palanisamy Muthukumar
    • 1
  • Bukke Kiran Naik
    • 1
  • Amarendra Goswami
    • 2
  1. 1.Department of Mechanical EngineeringIndian Institute of Technology GuwahatiGuwahatiIndia
  2. 2.Engineering SectionIndian Institute of Technology GuwahatiGuwahatiIndia

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