The compatibility between the needed structural designed dimensions of the irrigation works and the dimensions of the water stream or the canal in which the irrigation work will be located has a great importance from more than one point of view. As it is well known, the main aim of the designer of such works is to reach the optimum design for maximum performance efficiency with economical cost, and minimize negative technical impacts that may be harmful to the safety of the whole work. Since the complete suitability between the obtained designed dimensions of the different construction elements of the work, and the original properties and dimensions of the canal in which the work will be constructed, is rarely occurring. The designer always has to make some changes in the original engineering properties and dimensions of canals, such as bed width, bed level, and/or inside side slope, to reach the needed suitable compatibility between the structural design and the natural original canal cross section. For the economical purposes, the design always needs less width of the work, than the width of the bed of the original stream cross section, so a contraction may be needed where the work will be constructed; the literature indicated that, such a contraction must not be less than 0.6 of the original bed width. That contraction, of course, has a direct impact on the different hydraulic parameters, such as water depth, velocity, and flow regime in the location of the work. Changes of such hydraulic parameters may exceed their safe permissible values, and so the whole structure may face some dangerous situations, which must be overcome. In this paper, we present a technical survey of the previous research concerning canal width contraction, with the needed technical comments, and comparisons as a logical approach for a master-thesis under the same title.

Uplift is one of the main design factors for heading up works. This fact occupied the attention of many investigators in recent decades. The work presented herein comes as a trial for investigating the effect of arrangement of cutoffs and their depths on the uplift forces under the floor of diversion and head water structures. Cutoffs are one of the most important methods for decreasing the uplift forces if located at the right positions. Such positions are usually the beginning, the end of the solid apron, under the main heading up structure or combinations of them. The present study introduces an experimental investigation to clarify the precise behavior of the uplift forces due to the above mentioned locations. So, the experiments were carried out by providing the floor with one or two of cutoffs with different depths and locations. However, the sum of the total depths of the cutoff is kept constant and equal 20% of the floor length. The cutoffs were arranged in their locations to be at the beginning, end of the floor, or in-between to detect their effects on the uplift pressure. The obtained results for the studied cases proved that; for a fixed cut off depth, the nearer the location of such cutoff to the upstream the bigger the reduction of uplift distribution affecting the rest of the solid apron length. When the cutoff is used at the end of the floor, the reduction of the uplift force is not significant although its positive influence on exit gradient. The best location of cutoffs giving maximum uplift reduction is obtained. The results give a clear picture about the uplift distribution in longitudinal directions.

Uplift is one of the main design factors for heading up works. This fact occupied the attention of many investigators in recent decades. The work presented herein comes as a trial for investigating the effect of arrangement of cutoffs and their depths on the uplift forces under the floor of diversion and head water structures. Cutoffs are one of the most important methods for decreasing the uplift forces if located at the right positions. Such positions are usually the beginning, the end of the solid apron, under the main heading up structure or combinations of them. The present study introduces an experimental investigation to clarify the precise behavior of the uplift forces due to the above mentioned locations. So, the experiments were carried out by providing the floor with one or two of cutoffs with different depths and locations. However, the sum of the total depths of the cutoff is kept constant and equal 20% of the floor length. The cutoffs were arranged in their locations to be at the beginning, end of the floor, or in-between to detect their effects on the uplift pressure. The obtained results for the studied cases proved that; for a fixed cut off depth, the nearer the location of such cutoff to the upstream the bigger the reduction of uplift distribution affecting the rest of the solid apron length. When the cutoff is used at the end of the floor, the reduction of the uplift force is not significant although its positive influence on exit gradient. The best location of cutoffs giving maximum uplift reduction is obtained. The results give a clear picture about the uplift distribution in longitudinal directions.

Uplift is one of the main design factors for heading up works. This fact occupied the attention of many investigators in recent decades. The work presented herein comes as a trial for investigating the effect of arrangement of cutoffs and their depths on the uplift forces under the floor of diversion and head water structures. Cutoffs are one of the most important methods for decreasing the uplift forces if located at the right positions. Such positions are usually the beginning, the end of the solid apron, under the main heading up structure or combinations of them. The present study introduces an experimental investigation to clarify the precise behavior of the uplift forces due to the above mentioned locations. So, the experiments were carried out by providing the floor with one or two of cutoffs with different depths and locations. However, the sum of the total depths of the cutoff is kept constant and equal 20% of the floor length. The cutoffs were arranged in their locations to be at the beginning, end of the floor, or in-between to detect their effects on the uplift pressure. The obtained results for the studied cases proved that; for a fixed cut off depth, the nearer the location of such cutoff to the upstream the bigger the reduction of uplift distribution affecting the rest of the solid apron length. When the cutoff is used at the end of the floor, the reduction of the uplift force is not significant although its positive influence on exit gradient. The best location of cutoffs giving maximum uplift reduction is obtained. The results give a clear picture about the uplift distribution in longitudinal directions.

Uplift is one of the main design factors for heading up works. This fact occupied the attention of many investigators in recent decades. The work presented herein comes as a trial for investigating the effect of arrangement of cutoffs and their depths on the uplift forces under the floor of diversion and head water structures. Cutoffs are one of the most important methods for decreasing the uplift forces if located at the right positions. Such positions are usually the beginning, the end of the solid apron, under the main heading up structure or combinations of them. The present study introduces an experimental investigation to clarify the precise behavior of the uplift forces due to the above mentioned locations. So, the experiments were carried out by providing the floor with one or two of cutoffs with different depths and locations. However, the sum of the total depths of the cutoff is kept constant and equal 20% of the floor length. The cutoffs were arranged in their locations to be at the beginning, end of the floor, or in-between to detect their effects on the uplift pressure. The obtained results for the studied cases proved that; for a fixed cut off depth, the nearer the location of such cutoff to the upstream the bigger the reduction of uplift distribution affecting the rest of the solid apron length. When the cutoff is used at the end of the floor, the reduction of the uplift force is not significant although its positive influence on exit gradient. The best location of cutoffs giving maximum uplift reduction is obtained. The results give a clear picture about the uplift distribution in longitudinal directions.

Using of shrouded valve creates high swirl ratio inside the engine cylinder. Moreover, using of swirl generation device in the inlet port can improve this swirl ratio. In this paper, both twisted tap and guide vanes devices inserted in the inlet port are used individually for enhancing the generated swirl by the shrouded valve. In addition, the effect of these combinations on the volumetric efficiency and the turbulent kinetic energy (TKE) is studied. A three-dimensional simulation model based on SST k- ω model was used for predicting the air flow characteristics through the inlet port and the engine cylinder in both intake and compression strokes. The results showed that the using of twisted tap and guide vanes with the shrouded valve combinations increases the swirl ratio by 5.2% and 2%, respectively, at the start of injection. They also increase the TKE by 145% and 86.5% but they decrease the volumetric efficiency by about 3%.

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