METHOD OF INJECTING FLUID, A METHOD OF AND APPARATUS FOR CONTROLLING INJECTION OF FLUID, AND AN INTERNAL COMBUSTION ENGINE

In a method of injecting a fluid with a liquid-to-gas phase transition, the fluid is injected via a specified path of a change in an isobaric specific heat capacity per volume [Cp/V] of the fluid, the specified path leading from a temperature-pressure condition (i) to a temperature-pressure condition (ii). The condition (i) realizes an equality [Cp/V]=[Cp/V]L, where [Cp/V]L denotes an isobaric specific heat capacity per volume of the fluid in the liquid phase. The temperature-pressure condition (ii) realizes an equality [Cp/V]=[Cp/V]J, where [Cp/V]J denotes an isobaric specific heat capacity per volume of the fluid at timing of injection. The value [Cp/V]J is less than the value [Cp/V]L and included in a temperature-pressure region extending in close proximity to a high-temperature side of a temperature-pressure region corresponding to a temperature-pressure condition (iii) that realizes an isobaric specific heat capacity per volume [Cp/V]C greater than the value [Cp/V]L.