It is attractive to investigate the gas turbine engine by simulating technique, since it gives an improved understanding of engine dynamics and control problems without any dangers. And it will save both cost and time of engine development.
As a few examples of transient operations, the sudden changes of fuel flow rate during acceleration and deceleration are examined. It is shown clearly that the complicated dynamic behaviour of a small gas turbine can be analyzed, and these calculated results are compared with experimental data during the transient operations.
Pollutant emissions (CO, THC, NO_x and NO) from the gas turbine are measured and analyzed during acceleration and deceleration. Especially, the NO emission levels are calculated by the Zeldovich mechanism during accelerations, and these data are compared with those obtained experimentally. As can be seen, the data from both tests agreed with each other fairly well.

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For applying ceramics to engine parts, a method to measure flexural strength of ceramics was studied. Alumina and mullite were evaluated in flexural strength at high temperature. The ring flexural test method was proposed to obtain flexural strength simply and the results were compared with the ones obtained from the three point bending measurement. It was discussed also to have the influence of ring size on the difference of the measured values. The flexural strength of alumina and mullite ceramics at high temperature was measured for two cases. In one case the specimens were cut out from the virgin materials and in the other from the corroded materials exposed to combustion gas of kerosene, heavy oil and kerosene with ash constituents.
The results of these tests are summarized as follows:
(1) The ring flexural test method can be used for the evaluation of flexural strength.
(2) Alumina has the high flexural strength at the room temperature. But it decreases remarkably under the environment exposed to combustion gas at 600 °C to 1400 °C.
(3) Mullite shows an unusual phenomenon that the flexural strength at 1000°C is more than twice as high as it at room temperature. Corrosion resistance is slightly good, but the strength level and heat resistance are low as compared with other ceramics and engineering materials.

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NKK have developed a new type of control equipment for saving energy to the medium and small sized diesel ship.
That is the one making it possible to use turbo-generator whenever ship is sailing.
The conceptions of the control are as follows.
1) Turbo-generator is operated synchronously and shares the load with diesel generator.
2) Turbo-generator carries so much of the load which steam source can afford to generate, and diesel-generator carries the remaining. However the diesel-generator's load should not be lower than the limit, under which the operation yields a change for worse of the engine efficiency and causes to many kind of troubles.
NKK have already applied this equipment to the generating system in the 383rd ship in Shimizu Works and confirmed its effectiveness and practicability.
Now the consideration to apply this equipment has been started in many users, and in several ships the fitting has been already decided.

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Recently diesel engines for generators have become compact by applying a high-super charging system, and generators have also become small by applying a cylindrical type rotor.
So, momentary speed variations of the diesel generator system has been increased because of high super-charging of the engine and small GD² of the generator rotor. And the generator system whose engine has a little margin to the system output can not sometimes satisfy the rule requirement about the momentary speed variation in case of a loading condition being 0→50%→400%.
And so there are some cases that generator engines are obliged to have larger capacity for required output to the generator in order to satisfy the requirement of the speed variation and it causes a price increase for the generator system.
But after our research through some simulations, we have come to the conclusion that the capacity increase of the diesel engine can be avoided without any problems, if an appropriate protection device is provided.

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Container- and Ro/Ro-vessels are featured especially by the reduction of terminal time as a result of containerized cargo handling of lift-on/lift-off and roll-on/roll-off method, respectively. This paper analyzes the transportation energy efficiency of both vessels built in Japan so far, with paying attention to the feature mentioned above. Firstly the hull resistance characteristics are analyzed. In the same as car ferry, both vessels have the property being able to separate the hull function into buoyant support and cargo vessel. This property permits the hull form to have less resistance than general cargo ships. The performance level of hull resistance is same for all container-and Ro/Ro-vessels except the large, high speed container vessels with the speed above 26 knots and the displacement above 50, 000 tons, of which hull form are different because of the Panamax limit, and result in inferior level by about 30%. It is pointed out, therefore, that the enlargement of hull size over the Panamax limit is excessive as for the container ship. Secondly the cargo performance, which is indicated by the payload-to-displacement ratio, is analyzed. The payload of container- and Ro/Ro-vessels can be regarded as the carrying number of containers. The above ratio of container vessel is mainly determined by two factors of deadweight-to-displacement ratio and container number on deck loading. The deadweight-to-displacement ratio raises undesirably with speed. While it cannot be improved by the increase of displacement. Therefore the high speed container ship above 26 knots cannot have necessarily good cargo performance in spite of the design for increase of container number on deck loading. The cargo performance of the Ro/Ro ship is worse by two times than the container ship due to the roll-on/roll-off cargo handling method. This demerit sets off inevitably the merit that the Ro/Ro ship can handle cargoes without the special equipment ashore.

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