FLUID MECHANICS
CALIBRATION OF WIRES
RESULTS AND DISCUSSION
CALIBRATION OF WEIRS | |||||
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WEIR DIMENSIONS | |||||
Replication Number | “Ho” | H0(m) | Volume in L | Elapsed Time in seconds | Flowrate in m3/s |
1 | 62.5 | 0.0625 | 30 | 33.4 | 0.00090 |
2 | 56.2 | 0.0562 | 30 | 37.2 | 0.00081 |
3 | 52.6 | 0.0526 | 30 | 43.4 | 0.00069 |
4 | 42.9 | 0.0429 | 30 | 58.3 | 0.00051 |
5 | 34.0 | 0.0340 | 30 | 79.4 | 0.00038 |
6 | 20.1 | 0.0201 | 20 | 98.1 | 0.00031 |
Table 1 shows rectangular weir data
In the table 1, the Q(m3/s) is calculated from the Volume (v) dividing it by time (t).
Figure 1 plot Q vs. H0
From the figure 1, the value of n=0.985 which is not so close to the theoretical value of 1.50. The square R value is 0.921. The k value is 0.012. The Cd value is coming to be 0.1355.
WEIR DIMENSIONS | |||||
Replication Number | “Ho” | H0(m) | Volume in L | Elapsed Time in seconds | Flowrate in m3/s |
1 | 49.0 | 0.0490 | 35 | 39.3 | 0.00076 |
2 | 44.5 | 0.0445 | 35 | 50.9 | 0.00059 |
3 | 40.5 | 0.0405 | 35 | 61.8 | 0.00049 |
4 | 37.9 | 0.0379 | 35 | 75.9 | 0.00040 |
5 | 29.3 | 0.0293 | 35 | 135.8 | 0.00022 |
6 | 21.3 | 0.0213 | 10 | 69 | 0.00043 |
Table 2 shows triangular weir data
Figure 2 Plot Q vs H0
From the figure 2, the value of n=0.816 which is not so close to the theoretical value of 2.50. The square R value is 0.358. The k value is 0.006. The Cd value is coming to be 0.0677.
CONCLUSION
As the final results, the rectangular weir k=0.012, Cd=0.1355 and n =0.985 which really bad and not close to the theoretical value n=1.50.
While in the triangular weir k=0.006, Cd=0.0677 and n =0.816 which really bad and not close to the theoretical value n=2.50.
REFERENCES
- Bagheri S, Heidarpour M (2010) Flow over rectangular sharp-crested Irrig Sci 28:173–179
- Chanson H (1996) Free-surface flows with near-critical flow conditions. Can J Civ Eng 23(6):1272–1284 Chaudhry MH (1993) Open channel flow. Prentice Hall, Englewood Cliffs
- Finnemore EJ, Franzini JB (2002) Fluid mechanics with engineering applications. McGraw-Hill, New York
- Herschy H (1995) General purpose flow measurement equations for flumes and thin plate weirs. Flow Meas Instrum 6(4):283–293
