  A 1-D loop radiative hydrodynamic model that incorporates the effects of
gravitational stratification, heat conduction, radiative losses, external heat
input, presence of helium, and Braginskii viscosity is used to simulate
elementary flare loops. The physical parameters for the input are taken from
observations of the Bastille-Day flare of 2000 July 14. The present analysis
shows that: (a) The obtained maximum values of the electron density can be
considerably higher (4.2 X 10^{11} cm^{-3} or more) in the case of footpoint
heating than in the case of apex heating (2.5 X 10^{11} cm^{-3}). (b) The
average cooling time after the flare peak takes less time in the case of
footpoint heating than in the case of apex heating. (c) The peak apex
temperatures are significantly lower (by about 10 MK) for the case of footpoint
heating than for apex heating (for the same average loop temperature of about
30 MK). This characteristic allows us to discriminate between different heating
positioning. (d) In both cases (of apex and footpoint heating), the maximum
obtained apex temperature T^{max} is practically independent of the heating
duration sigma_{t}, but scales directly with the heating rate E_{H0}. (e) The
maximum obtained densities at the loop apex, n_e^{max}, increase with the
heating rate E_{H0} and heating duration sigma_{t} for both footpoint and apex
heating. In Paper II we will use the outputs of these hydrodynamic simulations,
which cover a wide range of the parameter space of heating rates and durations,
as an input for forward-fitting of the multi-loop arcade of the Bastille-day
flare. KEYWORDS: Sun: Flares -- Sun: Activity -- Sun: Corona
