Abstract: A plant with piping mounted on branch pipe, wherein said piping which introduces gas has a nozzle portion as a joint portion to a vessel and a branch portion connected with a branch pipe; and wherein an enlarged passage portion is formed at least at one of said branch portion and said nozzle portion, and a passage sectional area of said enlarged passage portion is larger than that of said piping other than said enlarged passage portion. Since the flow velocity of the gas flowing inside slows down at the enlarged passage portion, the occurrence of acoustic resonance at the branch portion or the nozzle portion can be suppressed. Accordingly, the fluctuation pressure of the gas flowing in the piping can be reduced even more.

Abstract: The object of the invention is to accurately evaluate integrity of vibration of a dryer of an actual system. The evaluating method for integrity of vibration of a steam dryer using a reduced model in a nuclear plant including the steam dryer for reducing moisture of steam generated inside a steam dome of a nuclear reactor pressure vessel, and a plurality of main steam pipes for transporting the steam to outside includes the steps of performing a steam test with the reduced model, calculating fluctuating stress applied to the steam dryer, and confirming integrity of vibration. According to the invention, it is possible to evaluate the pressure fluctuation of a dryer of an actual system more accurately.

Abstract: A plant with piping mounted on branch pipe, wherein said piping which introduces gas has a nozzle portion as a joint portion to a vessel and a branch portion connected with a branch pipe; and wherein an enlarged passage portion is formed at least at one of said branch portion and said nozzle portion, and a passage sectional area of said enlarged passage portion is larger than that of said piping other than said enlarged passage portion. Since the flow velocity of the gas flowing inside slows down at the enlarged passage portion, the occurrence of acoustic resonance at the branch portion or the nozzle portion can be suppressed. Accordingly, the fluctuation pressure of the gas flowing in the piping can be reduced even more.

Abstract: A subterranean environment evaluating apparatus and method, which measure, e.g., the geologic distribution coefficient in a subterranean environments using, e.g., a pit formed by boring. The subterranean environment evaluating apparatus comprises a geologic evaluation sensor, a pump, an analyzer, a PC, a data transmitter, etc., and it is disposed in the pit formed underground by boring. The geologic evaluation sensor is disposed to form a thin layer channel defined by the surface of a rock bed. Groundwater mixed with a tracer is caused to flow through the sensor, and the analyzer measures a change of tracer concentration in the groundwater between before and after contact of the groundwater with the rock bed. The PC determines a breakthrough curve from the change of tracer concentration, thereby calculating the distribution coefficient (Kd) between the rock bed and the groundwater and the effective diffusion coefficient of the rock bed.

Abstract: A subterranean environment evaluating apparatus and method, which measure, e.g., the geologic distribution coefficient in a subterranean environments using, e.g., a pit formed by boring. The subterranean environment evaluating apparatus comprises a geologic evaluation sensor, a pump, an analyzer, a PC, a data transmitter, etc., and it is disposed in the pit formed underground by boring. The geologic evaluation sensor is disposed to form a thin layer channel defined by the surface of a rock bed. Groundwater mixed with a tracer is caused to flow through the sensor, and the analyzer measures a change of tracer concentration in the groundwater between before and after contact of the groundwater with the rock bed. The PC determines a breakthrough curve from the change of tracer concentration, thereby calculating the distribution coefficient (Kd) between the rock bed and the groundwater and the effective diffusion coefficient of the rock bed.