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. [...]
[...] This Bench Top cooling tower experiment was carried out for four separate combinations of the cooling load, water flow rate and the air flow rate. The design of experiment was carried out in a manner in which various different temperatures were measured for either a low or a high value for each of the parameters. The design of the experiment for the parameters; cooling load, water flow rate and air flow rate respectively were in the order of [low, low, low], [low, high, low], [high, high, low], [high, high, high]. [...]
[...] The actual values of a Bench Top Cooling Tower vary between 10 and 15 The best approach ( 1.05 is shown with respect to the mass flow rate of water although the approach with respect to the cooling load displays a close value. The actual values of approach for a Bench Top Cooling Tower vary between 1 and 2 Table Best Values of Range and Approach with respect to different Factors Factor Best Range Best Approach The best possible values of range and approach are extremely close and within the range of the actual values obtained by observation of the tower. [...]
[...] Q actual = CD Q theoretical Equation below represents the method in which the mass flow rate of air ‘ma' was calculated in order to be used in equation The other parameters are the same as defined previously. ma = ? Q actual Equation below represents the equation used to determine the humidity ratio at the inlet as well as the outlet of the system, which was used in equation ? = mass of water vapor/ mass of dry air The following equation represents the make-up mass flow rate make-up' which is the flow rate of the water, which was supplied to the water circuit to compensate for the water removed from the water circuit, due to evaporation and drift, determined by taking the difference between the inlet and outlet mass flow rates of water. [...]
using our reader.