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A multi-fluid model for an atomic hydrogen-proton mixture in the upperatmosphere of extrosolar planet is presented when the continuity and momentumequations of each component have been already solved with an energy equation.The particle number density, the temperature distribution and the structure ofvelocity can be found by means of the model. We chose two special objects, HD209458b and HD 189733b, as discussion samples and the conclusion is that theirmass loss rates predicted by the model are in accordance with those ofobservation. The most important physical process in coupling each component ischarge exchange which tightly couples atomic hydrogen with protons. Most of thehydrogen escaping from hot Jupiters is protons, especially in young star-planetsystem. We found that the single-fluid model can describe the escape ofparticles when the mass loss rate is higher than a few times $10^{9}$ g/s whilebelow $10^{9}$ g/s the multi-fluid model is more suitable for it due to thedecoupling of particles. We found that the predicted mass loss rates of HD189733b with the assumption of energy-limit are a factor of 10 larger than thatcalculated by our models due to the high ionization degree. For the ionizedwind which is almost compose of protons, the assumption of energy-limit is nolonger effective. We fitted the mass loss rates of the ionized wind as afunction of $F_{UV}$ by calculating the variation of the mass loss rates withUV fluxes.

Escaping Particle fluxes in the atmospheres of close-in exoplanets: I. model of hydrogen