Hydraulic Study on the Rearing Facilities for the Spawn of Prawn，Penaeus Japonicus S_<PENCE> B_<ATE>

In order to investigate the surface profile of supply waterway with close end and many orifices on both walls, the hydraulic test was carried out by the writer. The following results were obtained: 1) Total loss head △His △H=((f〓)/(12)・(l)/(R)+(Nf_1)/(4))(V^2_A)/(2g) where, R: hydraulic mcan radius, N: numbers of orifices, V_A: upstream velocity, f: ^1_<C_〓>^^12-1, C_〓: velocity coefficient, f: coefficient of fluid resistance. According to his culculation, △H is about 0.3^m/_m in this test case, and the surface profile is to be almost level. 2) Time to keep equilibrium (T) is T=(2・303Q・A)/(N^2・C^〓・α＾2・g) log_<10>√<H_m>/√<H^m-H>-√<2A>/√<N・C・a・√<2g>>√H where Q: discharge, A: surface area, C: discharge coefficient, ....