789. 乱流ナトリウム流れの管摩擦係数

抄録

An experimental investigation is made of the friction factor for fully developed turbulent sodium flow in small smooth tubes. Pressure drop for single and double tubes is measured by means of NaK pressure transducers, under several sets of conditions of fluid flow, temperature and metallic impurity.
From the results obtained it is found that the friction factor-Reynolds number relationships for the small tubes vary fairly with the operating time of the sodium loop (about 1, 260-4, 100h). The primary cause of the characteristic change is the deposition of fine metallic impurities on the tube surfaces.