Lab (abstract, results and discussion)
Paper instructions:
This week, your task is to design an experiment for the Shell & Tube Heat Exchanger.

You must use your knowledge of Chemical Engineering and your other resources to:

 

1. Calculate the duty of the system.

2. Assess whether the Dittus Boelter or the Gnielinski Correlation best applies to

the system. Is one better under certain conditions?

3. Estimate the wall thickness of a tube, assuming the material is copper.
Edit and write ( professional writing and all sentences are connected)

no sentence repeating
Abstract:
***The objective of this experiment is to study the function and the working of shell andtube heat exchanger. Calculations on the heat transfer and heat loss were carried outfor energy balance study.
The average amount of calcium carbonate collected by using one plate was 34 grams as compared to 11 grams collected when using two plates.
To make outlet temperature significant, a constant gauge pressure of 6 psig and varies the volumetric flow rate that was used, keeping pressure drop throughout the system constant. During each trail, shell and tube heat exchanger was run for two minutes to remove time as a potential variable. Since pressure drop and time were kept constant through each trial of the experiment, the duty was calculated which was 281.63 kJ/s. using Gnielinskiequction is better than Dittus-Boelter equation due to Reynolds number is greater than 3000.
Results and discussion:
Effect of flow rate of the cold fluid:
Increased the flow rate of cold fluid results in increase in the overall heat transfer coefficient. This is because in the flow rate increase the Reynold number will increase???. This caused the outlet temperature to decrease. Since the volumetric flow rate increased, caused the mass flow rate to increase as a result faster rate. The specific heat is constant, thentube outlet temperature decreased to comply with law of conservation of energy. The increase in flow rate of one of the stream will results in an increase in the rate of heat transfer.
Possible sources of error could have been introduced throughout the experiment. Pressure gauges fluctuate between 3 and 6 psi, it caused to decrease the outlet temperature. Since the time and pressures is fix value. It affected the reading of the outlet temperature. Flow rate is also another source of error, Which . Despite these possible sources of error, the data still showed a substantial difference in the duty in the last run.

From the data in Table 3 and Table 4, the temperature differences under constant flowrates are shown. Under constant flow rate conditions, the ratio between temperature differencesis also constant. If there is a rise in the temperature difference of the hot fluid, there will also bea rise in the temperature difference in the cold fluid. This is governed by a special case of theFirst Law of Thermodynamics. In this case, the energy is transferred from hot to cold fluids withconstant mass flow rates. Therefore the ratio between temperature differences does not changeeven though the numerical values of the temperature differences may change
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M[gpm] 0.5 M[gpm] 1.5 M[gpm] 2.5 M[gpm] 3.5
Trial #1 Trial #1 Trial #1 Trial #1
Tin [F] 72 Tin [F] 66 Tin [F] 66 Tin [F] 66
Tout [F] 201 Tout [F] 192 Tout [F] 165 Tout [F] 158
Pin [psi] 5 Pin [psi] 5 Pin [psi] 5 Pin [psi] 5 Ashell 240 in2
Time [min] 2 Time [min] 2 Time [min] 2 Time [min] 2 Tube Diameter 0.25
Number of Tubes 56
Trial #2 Trial #2 Trial #2 Trial #2 Shell Diameter 10 in.
Tin [F] 72 Tin [F] 66 Tin [F] 66 Tin [F] 66 Tube Length 2 ft.
Tout [F] 197 Tout [F] 161 Tout [F] 165 Tout [F] 159 Water Density 995 kg/m3
Pin [psi] 5 Pin [psi] 5 Pin [psi] 5 Pin [psi] 5
Time [min] 2 Time [min] 2 Time [min] 2 Time [min] 2

Trial #3 Trial #3 Trial #3 Trial #3
Tin [F] 70 Tin [F] 66 Tin [F] 66 Tin [F] 66
Tout [F] 197 Tout [F] 177 Tout [F] 162 Tout [F] 152
Pin [psi] 5 Pin [psi] 5 Pin [psi] 5 Pin [psi] 5
Time [min] 2 Time [min] 2 Time [min] 2 Time [min] 2

dT 127 110.67 98 90.33