Search Results

You are looking at 1 - 4 of 4 items for :

  • Author or Editor: S. Hameed x
  • Journal of Applied Meteorology and Climatology x
  • Refine by Access: All Content x
Clear All Modify Search
S. A. Lebedeff
and
S. Hameed

Abstract

Full access
S. A. Lebedeff
and
S. Hameed

Abstract

The two-dimensional diffusion equation has been solved by an integral method to obtain the distribution of ground-level concentration of an inert effluent emitted from a semi-infinite area source in a steady-state and horizontally homogeneous atmospheric surface layer. Mean wind velocity and eddy diffusivity profiles derived from empirically determined flux-profile relations of Businger et al. (1971) for stable and unstable surface layers were used. It is found that concentration as a function of downwind distance can be described by a simple formula over distances of practical interest in surface layer dispersion. Corresponding results for a cross-wind infinite line source are obtained by simple differentiation. The concentration distribution is completely determined by the friction velocity u *, the Monin-Obukhov length L, the roughness length z0, and the effluent source strength Q. The generalization of the integral method needed to obtain accurate solutions of the diffusion equation with the given wind velocity and diffusivity profiles is discussed in an appendix.

Full access
S. A. Lebedeff
and
S. Hameed

Abstract

Turbulent transport of material emitted from a surface may be described by the steady-state, two-dimensional, semi-empirical diffusion equation. It is shown that, with wind velocity and eddy diffusivity expressed as power functions of the vertical coordinate, this equation can be solved exactly by introducing a similarity variable. The solution gives the vertical distribution of concentration for area sources in terms of the incomplete gamma function. Implications of the solution are discussed.

Full access
Hameed Rasheed
,
A. S. Aldabagh
, and
Murur V. Ramamoorthy

Abstract

Power transformation was used to normalize the peak daily and peak monthly rainfall at various raingage stations in Iraq. Excellent correlations were found between the coefficient of skewness (Cs ) and a parameter for power transformation (λ), coefficient of kurtosis (Ck ) and λ, and between Cs and Ck . The relationship between Cs and λ is used to develop an estimation procedure for calculation of the transformation parameter. The method eliminates the use of trial and error for estimating λ. The method has been used for estimating T-year peak daily and peak monthly rainfall by power transformation. The results are compared with results from other methods.

Full access