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Table 7

Head discharge observations (experimental and CFD approach) for modified compound weir geometry

Sr. No.	Head over weir, h (expt) (cm)	Time to collect 100 litres (sec)	Q_expt (lps)	Q_CFD (lps)	Q_th (lps) for corresponding step size	C_d (expt approach)=[Q_expt/Q_th]×0.6	C_d (CFD approach)	Remarks
1	4.87	49.79	2.006	2.01	2	0.6	0.6	Exact prediction of discharge values. C_d remains constant for various flow ranges
2	6.03	35.502	2.82	2.82	2.8	0.596	0.6
3	7.01	27.784	3.59	3.6	3.6	0.594	0.6
4	7.89	22.622	4.42	4.39	4.4	0.602	0.6
5	8.68	19.134	5.22	5.19	5.2	0.602	0.6
6	9.41	16.554	6.03	5.97	6	0.598	0.6
7	10.08	14.682	6.806	6.78	6.8	0.596	0.6
8	10.78	13.152	7.602	7.68	7.6	0.596	0.61
9	11.31	11.81	8.47	8.53	8.4	0.6	0.61
10	11.87	10.822	9.24	9.45	9.2	0.6	0.62

Sr. No.	Head over weir, h (expt) (cm)	Time to collect 100 litres (sec)	Q_expt (lps)	Q_CFD (lps)	Q_th (lps) for corresponding step size	C_d (expt approach)=[Q_expt/Q_th]×0.6	C_d (CFD approach)	Remarks
1	4.87	49.79	2.006	2.01	2	0.6	0.6	Exact prediction of discharge values. C_d remains constant for various flow ranges
2	6.03	35.502	2.82	2.82	2.8	0.596	0.6
3	7.01	27.784	3.59	3.6	3.6	0.594	0.6
4	7.89	22.622	4.42	4.39	4.4	0.602	0.6
5	8.68	19.134	5.22	5.19	5.2	0.602	0.6
6	9.41	16.554	6.03	5.97	6	0.598	0.6
7	10.08	14.682	6.806	6.78	6.8	0.596	0.6
8	10.78	13.152	7.602	7.68	7.6	0.596	0.61
9	11.31	11.81	8.47	8.53	8.4	0.6	0.61
10	11.87	10.822	9.24	9.45	9.2	0.6	0.62