Question 174Steam Plants - 1st Asst/Chief

The correct answer is C) calorimeter. The BTU (British Thermal Unit) value of fuel oil is determined by a calorimeter, which is a device used to measure the amount of heat energy released during the combustion of a fuel. By burning a known quantity of the fuel in the calorimeter and measuring the resulting temperature increase, the BTU value can be calculated. The other answer choices are incorrect because they do not directly measure the BTU value. An open cup test measures the flash point of the fuel, a hydrometer measures the density, and a viscosimeter measures the viscosity, but none of these methods directly determine the BTU content of the fuel.