ENGINE CYLINDER COOLING DEVICE, CYLINDER COOLING METHOD, METHOD OF MODIFYING CYLINDER COOLING DEVICE, AND ENGINE AND SHIP EACH EQUIPPED WITH CYLINDER COOLING DEVICE

摘要

PROBLEM TO BE SOLVED: To prevent a cylinder liner from being overcooled during partial load operation of an engine and suppress low temperature corrosion.SOLUTION: A cylinder cooling device 30A comprises: a communication partition valve 37 isolating a cooling water passage 32 corresponding to the position of a low temperature area of a cylinder liner 6 from the other cooling water passages 31 and 33; a discharge valve 46 discharging cooling water flowing in the cooling water passage 32; a temperature measuring unit 48 measuring the temperature of the low temperature area; and a controller 50 controlling the communication partition valve 37 and the discharge valve 46 to be opened or closed depending on temperature data input from the temperature measuring unit 48. The controller 50 closes the communication partition valve 37 and opens the discharge valve 46 to thereby temporarily discharge the cooling water in the cooling water passage 32 if the temperature of the low temperature area falls below a cooling critical temperature that is a critical point at which it is determined whether to cool the cylinder liner 6, and opens the communication partition valve 37, closes the discharge valve 46, and re-feed the cooling water to the cooling water passage 32 if the temperature of the low temperature area exceeds the cooling critical temperature.