Bench top cooling tower
- Experimental setup and procedure
- The cooling tower experiment
- The flow control valve
- Bench top cooling
- Results and discussions
The cooling tower experiment was carried out using a Bench Top Cooling tower with an orifice at the top. In this case a wet cooling tower, where the coolant comes in to direct contact with atmospheric air and undergo energy and mass transfer was taken in to consideration. The best possible values for the range and the approach were determined and compared to the actual values. The best range was determined to be 10.38 C and the best approach to be 1.05 C. The cooling tower operates best at highest range values and lowest approach values.
Make-up water flow rate or in other words evaporation of water as waste was measured as well as calculated using a mass balance equation. The measured and the calculated make-up mass flow rates showed a deviation of 3.1% with respect to the higher cooling load of 1.5kW.
[...] = - Figure Sketch of Cooling Tower Indicating Air and Water Inlets and Outlets Equation represents the mass balance equation used in order to calculate the mass flow rate of water at the outlet (mH2O, out). ?ma' represents the mass flow rate of air in the system. ??in' and ??out' represent the humidity ratio at the inlet and outlet of the system. In the following equation the mass flow rate of air was calculated using the pressure drop of the orifice plate. [...]
[...] Experimental Setup & Procedure The cooling tower experiment was carried out by first removing the plastic cover and studying and identifying the parts, instruments and their locations. The separate paths for air and water were also studied. Precautions and warnings were taken in to consideration in order to prevent any harm to the participants and to avoid any damage to the apparatus. Then the load tank drain valve was opened and packings were wet down with distilled water by inserting the hose through the orifice. [...]
[...] Figure Variation of Range & Approach with respect to Cooling Load According to Figure the cooling range (difference between the liquid water temperature to and exit from the tower3) and approach (Difference between the temperature of the liquid water exiting the tower and the wet bulb temperature of the air entering the tower3) both increase as the cooling load increases. The range curve has a higher gradient than that of the approach curve. At the lower cooling load value kW) both the range and the approach show similar values, where as the higher cooling load ( 1.5 kW) show a significant increase in the range with respect to the approach. [...]