The dynamical gas flow through an exhaust valve in Diesel engine has never been reported clearly.
The authors have made the experimental equipment so as to open and shut the exhaust valve by compressed air, in order to examine the gas flow through the exhaust valve using air during the whole valve opening interval.
Using the equipment, we have obtained the dynamical discharge coefficients of the exhaust valve with the face angle 30 and 45 degrees.
The obtained dynamical discharge coefficients at every step of the valve openings were compared with the steady discharge coefficients of the exhaust valve reported previously¹⁾ by the authors.
It was resulted from comparing the discharge coefficients in case of statical and dynamical tests that these both discharge coefficients change with similar tendency each other.
So that, it is able to know approximately the hydrodynamical gas flow through exhaust valve on the statical tests without the dynamical tests.

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Burmeister & Wain, Copenhagen has developed a long stroke version of K-GF engines, to be designated as L-GF, to meet the demand of market emerging in the wake of the energy crisis which meant a return to a situation with an importance of fuel prices relative to other costs as known before 1960.
The change from K-GF to L-GF means an 18% reduction of rpm., resulting in a 5% increase in propulsion efficiency which, again, corresponds to a reduction of fuel consumption of approximately 5%.
The engines have been designed to retain identy with the K-GF series in the majority of components and operate at the same pressures and levels of loading, thus keeping the same degree of reliability as of well proven K-GF engines.

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For the stern tube seal liner, high chrome stainless steel made by centrifugal casting is generally used. This material, though high resistance against corrosion and abrasion, is in some instances subjected to pitting corrosion on the seal rubber sliding surface or to its abnormal abrasion, depending upon the environment and the conditions of using. Looking into the cause of such damage and as the preventive method thereof, a new material has been developed for seal liner and electrical protection method for corrosion has been also investigated.

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