We investigate the ideal single-cycle, single-tube pulse detonation performance of partially oxidized jet fuel. The analysis is based on a sequence of ideal combustion and mixing processes using thermodynamic computations based on a realistic set of product species and thermochemical properties. The calculated specific impulse of partially-oxidized fuel is compared to the reference case of detonating the original fuel in air. Partially oxidized fuel always has a smaller impulse than the original fuel and the specific impulse increases with increasing partial oxidation equivalence ratio. For a partial oxidation equivalence ratio of 2, the impulse is reduced to about 60% of the reference case; for a partial oxidation equivalence ratio of 4, the impulse is reduced to 80% of the reference case. In the second part of the present study, we report numerical simulations, analysis, and experimental studies of detonation cell width of the mixtures investigated in the first part. We find that the detonation cell width is predicted to be a minimum for a partial oxidation equivalence ratio Φ{sub}b of approximately 3. This minimum is shown to be a consequence of thermodynamic and chemical kinetic factors, mainly that the largest mole fractions of H{sub}2 and CO occur after the primary burn for Φ{sub}(b～3). Detonation cell size measurements with synthetic mixtures of partial oxidation products and air were carried out in the Caltech 280-mm diameter detonation tube for partial oxidation equivalence ratios of 2 and 3. This data and numerical computations are used to estimate minimum detonation cell widths of 22-24 mm at 1 atm and 3-9 mm at 6 atm, depending on the initial temperature (24-404°C). Comparison with estimated cell widths for the detonation of a representative hydrocarbon fuel (propane) without partial oxidation indicate that, at best, a factor of two reduction in detonation cell size can be achieved by partial oxidation.
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