An analysis is presented which describes and predicts the process of drainage of noxious liquid substances from piping arrangement consisted of horizontal and vertical pipe line in chemical tanker during the operation of air blowing. The process is modeled in three stages according to the location of the head of flowing single air slug in pipe line, that is,
stage 1: the head of slug locates in horizontal pipe,
stage 2: the head locates in vertical pipe,
stage 3: the head locates outside the outlet of pipe line.
Analytical expression is derived by taking into account the important factors in each stage.
The results predicted by the analysis in stage 1 and stage 2 are compared with experimental data obtained for various operational conditions using water and air as working fluid. Good agreement with experimantal data of pressure and the quantity of residue in horizontal pipe are shown.

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In developing marine engines, optimum specifications, which meet customers' needs and market trends, well-balanced in various aspects such as reliability, performance and price, must be sought.
Among the specifications, the engine weight has a close connection with the reliability and performance, and the reduction in engine weight, which leads to a larger cargo capacity and a more compact engine room of the ship, is one of the major factors.
If the planning of the engine can be forwarded while estimating the engine weight accurately from the early stage of development, the optimum principal particulars of engine can be selected rationally and efficiently.
In this study, the degree of influence of each item on the engine particulars has been analyzed by means of the weight simulation method for the low speed two-stroke cycle crosshead diesel engines.
The fruits of this study can be summarized as follows.
(1) The degree of influence of principal particulars on the total weight and specific weight per output of the engines has been analyzed and clarified quantitatively.
(2) The simple evaluating formulas, by which the engine weight can be estimated and evaluated easily from the principal particulars when planning the engine, can be introduced by applying the results of these analyses.
(3) It has been clarified that the principal particulars, which are most suitable for the specification being aimed at and have good balance, can be selected rationally by introducing the relationships between the principal particulars and the reliability and the performance together with these results of the engine weight analyses.

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Liquid-liquid direct contact heat exchangers have many advantages over conventional multi-tubular type exchangers from the point of view of area of heat exchange and scaling. However, the mechanism of liquid-liquid direct contact heat exchange is so complicated that many experimental researches are going on.
Hot water and n-Pentane are mixed and exchanged each other in a acrylic cylinder, 40 mm dia. and 220 mm height, of our experimental apparatus.
It is the main object of our research to observe flooding phenomenon of n-Pentane from the cylinder since research reports about the flooding phenomenon are very rare and a portion of liquid n-Pentane still exists in hot water at higher temperature than its boiling point. The evaporation rate of n-Pentane is an important scale of exchanged heat flux between hot water and n-Pentane.
We have found evaporation rate of n-Pentane (evaporated n-Pentane/injected n-Pentane) from the measurement of flooding n-Pentane. From the measurement results, the evaporation rate (λ) is expressed by superheated temperature (ΔT_W) of hot water and the mass flow rate (φ=n-Pentane/hot water) . Equation of the rate is obtained as follow;
λ=1-exp{-[ΔT_w-(10∅+2.0)/16∅^0.6]} where ΔT_W = T_l-T_b
T_l: Inlet hot water temperature (K) . T_b : Boiling temperature of water and n-Pentane mixture (K) . φ : Mass flow rate (n-Pentane/hot water) .
The equation is in accord with the experimental results in all superheated temperature region at hot water flow of 8.33×10^-6 (m³/s) . And it differs about 5-10% at hot water flow of 16.7×10^-6 (m³/s) . The experimental equation can be adopted to estimate evaporation rate, and the experimental process is acceptable to observe the flooding phenomenon in Liquid-Liquid Direct Contanct Heat Exchange.

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