Hayao Akizawa
University of Tokyo
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Journal of the Marine Engineering Society in Japan | 1992
Hisaharu Sakai; Sadami Yada; Hiroaki Yonemoto; Hayao Akizawa
The space for acommodation and engine room of a fishing boat are much narrower than those of a merchant ship. Thus it is impossible to install all lighting apparatus on the required position. Judging from ”the recommended levels of illumination” of the Japanese lndustrial Standard, some parts where illuminance are lower than the standard level are found.The heigh frequency operation of the fluorescent lamp. as the countermeasures of increase in the illumination and decrease in the electric power were noted. Likewise, experiments on the fundamental characteristic amd the continuous action performance were conducted to compare the electronic invertor ballast and the conventional coil ballast.The following could be concluded;1) Performance of the fluorescent lamp using invertor ballast was independent of f luctuatuons in the voltage and frequency of power source.2) Luminous flux amd luminous efficiency of the fluorescent lamp using the invertor ballast increased to 18% and 23% respectively, compared with those using coil ballast.3) Each secular change of luminous flux showed approximately a similar decreasing tendency. The extended lifetime of the fluorescent lamp was assumed to be 107 days approximately in consideration of the increased luminous flux within the invertor ballast.4) Saving of running cost using high frequency operation was estimated to be 142, 000 yen per year on a research and training fishing boat.
Journal of the Marine Engineering Society in Japan | 1991
Hisaharu Sakai; Sadami Yada; Hiroaki Yonemoto; Yosuke Kitano; Hayao Akizawa
Experiments on twe variable discharge systems of cooling sea water pump for main engine and for generator engines were conducted to evaluate the effects of electric power saving. One was a combination of a general purpose inverter, an automatic controller and a pair of temperature sensors, and maintained the required temperature difference of cooling sea water between inlet and outlet of main engine. The other was a combination of the inverter, the controller and a pressure sensor, and maintained the required delivery pressure within cooling sea water pump for generator engines.The results showed that it was possible to control the discharge of these pumps, so that the temperature difference amd delivery pressure were kept constant all the time. These systems could save the electric power consumption. In the case of the cooling sea water pump for main engine, the cost of equipment could be offset from the saving of the running cost in approximately 2 years, also the cooling sea water pump for generator engine, 0.6 years. These were suitable for small-powered pump unit (5.5-7.5 kW ) on fishing vessels, these methods also could be widely introduced to fishery machines.
Journal of the Marine Engineering Society in Japan | 1989
Hisaharu Sakai; Hayao Akizawa; Yosuke Kitano; Katsuyuki Yamane
Determination of generator capacity on fishing and training vessel is based on the estimations of necessary power under the various operating conditions, using the electric power consmption table, the same table as a merchant ship uses, which is adopted also on fishing boat. In spite of such a determination on Shinyo-maru (Tokyo University of Fisheries), generator was forced the operation under low load.We researched, here the operationg condition of automatic start-stop machines on Shinyo-maru, as well as the power consumptions on large fishing and training vessels of other national universities.Then we found out the real situation concerning the necessary power on fishing and training vessel, and the difference between the standpoints of a merchant ship and ours concerning the table. The diversity factor and demand factor were also estimated.We came to the following conclusions;1) The operations of the generator under low load frequently occurred.2) Comparing to a merchant ship, we are apt to overestimate the necessary power.3) As the special generator during the anchorage generate little electricity, which can hardly supply the airconditioning units with enough power, generator capacity of that suitable for all-seasuns, is, therefoer, desirable.4) As a value of diversity factor, we recommend the use of 35%, 5) Normal necessary power (Y) under summer service condition is related to gross tonnage (X), complement (Z) and length between perpendiculars (W), by the following equations.Y=0.0988X+59.0, Y=2.11Z-25.5, Y=6.72W-232
Nippon Suisan Gakkaishi | 1987
Masanobu Ishikawa; Kaname Sato; Hayao Akizawa; Yoshio Sakai; Hisahiko Watanabe
Nippon Suisan Gakkaishi | 1989
Kaname Sato; Hisahiko Watanabe; Masanobu Ishikawa; Hayao Akizawa
Nippon Suisan Gakkaishi | 1991
Hisaharu Sakai; Kaname Satoh; Sadami Yada; Yosuke Kitano; Hiroaki Yonemoto; Katsuyuki Yamane; Hayao Akizawa
Nippon Suisan Gakkaishi | 1990
Hisaharu Sakai; Kaname Satoh; Sadami Yada; Yosuke Kitano; Hiroaki Yonemoto; Katsuyuki Yamane; Hayao Akizawa
Journal of Fisheries Engineering | 1993
Sadami Yada; Hayao Akizawa; Hisaharu Sakai; Makio Sakamoto
Marine engineering | 1990
Hisaharu Sakai; Yosuke Kitano; Kazuya Kumagae; Katsuyuki Yamane; Jiro Asida; Hayao Akizawa
Journal of the Marine Engineering Society in Japan | 1990
Hisaharu Sakai; Sadami Yada; Makio Sakamoto; Hayao Akizawa