considering the importance of adequate roughness coefficient estimation in river engineering studies, evaluation of image processing technique in estimating manning’s roughness coefficient in the surface layer of riverbeds carried out in this study. the mentioned approach evaluation conducted by implementing of sieving analysis and digital image processing methods simultaneously for a 7.5km rea...

The present paper is an experimental investigation of roughness effects on nucleate pool boiling of refrigerant R113 on horizontal circular copper surfaces. The copper samples were treated by different sand paper grit sizes to achieve different surface roughness. The average surface roughness of the four samples was 0.901, 0.735, 0.65, and 0.09, respectively. The experiments were performed in t...

Influence of initial surface roughness on friction and wear processes under fretting conditions was investigated experimentally. Rough surfaces (Ra=0.15-2.52 μm) were prepared on two materials: carbon alloy (AISI 1034) and titanium alloy (Ti-6Al-4V). Strong influence of initial surface roughness on friction and wear processes is reported for both tested materials. Lower coefficient of friction ...

The goal of this study is to assess the rehabilitation Bahr Awlad Mohamed canal.The canal was rehabilitated by installing lining trapezoidal cross-sections. Before and after process, a field investigation, hydraulic hydrographic measurements, mathematical model (Sobek – 1D) were conducted. According findings, canal's improved average water velocity from 0.18 m/s 0.32 m/s, Manning roughness coef...

Abstract Urbanization and climate change have resulted in an increase catchment runoff, often exceeding the designed capacity of sewer systems. The decision to modernize a system should be based on appropriate criteria. In engineering practice, above is commonly achieved using hydrodynamic model simulation various rainfall events. article presents methodology analyze effect characteristics para...

The effect of surface roughness on the Seebeck coefficient in the sub-50-nm scale silicon ultra thin films is investigated theoretically using nonequilibrium Green's function formalism. For systematic studies, the surface roughness is modelled by varying thickness periodically with square wave profile characterized by two parameters: amplitude (A 0) and wavelength (λ). Since high Seebeck coeffi...