The Use of Availability and Energy Balances in Diesel Engines 890822
In this study the application of an availability balance and two alternative forms of energy balance to two experimental single-cylinder engines, a water-cooled and an uncooled diesel, are described. Both the first-law efficiency and the second-law efficiency of the uncooled engine were significantly higher than those of the water-cooled engine for equal BMEP levels. The loss of availability due to irreversibilities accounted for as much as 50% of the input fuel availability at light loads. Based on an energy balance, the heat loss from the uncooled engine was found to range from 50 to 70% of the corresponding heat loss from the water-cooled engine.