Cape Peninsula University of TechnologyBellville Campus

Department of Mechanical Engineering

THERMODYNAMICS LABORATORY

BOILER EFFICIENCY & CONDENSERS

By

L. Nyandu

Subject: APT200SLecturer: Mr Magoda

Evaluation Criteria

Introduction: (Aim for each lab, Background, List of the apparatus, Procedure etc)

10%

Result: (Calculations, Correct method, etc) 55%

Explanations (did you explain what you are doing rather than put formulas.)

10%

Discussion: (Discussion of the results, do they make sense? Any possible errors, etc)

10%

Conclusion and Recommendations: (Did we achieve our aims? What do we need to do to improve our results)

5%

Presentation, layout and neatness: (Cover page, Typed/ print neat, report format, etc)

10%

Total 100%

Date of submission: 28/10/2014

LAB 1: BOILER EFFICIENCY & CONDENSERS

The aim of this experiment is to determine boiler efficiency and equivalent evaporator.

1. Apparatus Steam boiler plant. Separating and throttling calorimeter and a Measuring beaker.

2. Procedure Boiler was switched off, and then switched on. The boiler was run for 7 minutes, 31 seconds. Take readings from the pressure gauge (740 kPa) and add with the atmospheric

pressure to determine the absolute pressure. Take the readings of the thermometer from the feed water. Take the readings of the volume of fuel and the steam mass.

3. Results

Determine the mass of the fluid:

M f=V f × ρ

¿0.00287×6010×840=14,465kg/h

Mass of the Steam as read from experiment:

M s=318.18kg/h

h0=CP×t 0

¿4.187×18

¿75.366kJ /kg

Boiler efficiency determined:

ƞ0=M s(h¿−h0)M f ×CV

¿318.18×(2860.29−75.366)

25.2×45500

¿78.72%

Equivalent Evaporation determined:

EE=M s(h¿−h0)M f ×2257

¿318×(2860.29−75.366)

14.465×2257

¿27.126 kg steamkg fuel

Rackine efficiency determined:

ƞR=(h1−h2)(h1−h3)

¿(h¿−hwet )(h¿−h f @75)

¿(2860.29−1987.89)(2860.29−384.4 )

¿35.23%

Readings taken from experiment

Reading UnitsVolume of fuel 2.87×10−6 m3

Time 7 minMass flow rate of steam 318 kg/hCV of fuel 45 MJ/kgDensity of fuel 0.84 kg/L

Figure 3: The above table shows the experimental readings for the boiler efficiency &

condensers lab.

4. Discussion

The efficiency of the boiler is found to be 77.43%, the rankine efficiency is 35.23% and the equivalent evaporator determined is 15.754. This is what we expected because the boiler efficiency is greater than 75% and rankine efficiency is less than 40%.

5. Conclusion

Looking at the results of the experiment done for the boiler lab, it was found that the boiler had the more than 75% of efficiency as it was expected because the reading for the efficiency is 77.34% which then sows than the experiment was a success. The Rankin cycle’s efficiency is found to be less than 40% percent and that is what we have expected based on the literature we know.

6. Recommendations

In order to make results more precisely, the students should be given time to repeat the lab more than two times to ensure that students get the correct readings. There should be enough data sheets given for instructions on how to carry the experiment of the boiler reading with the procedure included and every apparatus.