The present thesis offers two methods for the analysis and design of long columns according to the new Egyptian code for limit state design of reinforced concrete structures. A theoretical study of the basic assumptions and methods of stress analysis of columns subject to axial loads, biaxial moment is presented. A computer program to carry out the above analysis and create the interaction surface for long column which taking the boundary conditions into consideration is developed. ”A simple method to design long column according the code of practice has been derived and presented in closed form >and design tables. Two realistic columns of different shapes, reinforcement and end conditions have been used to demonstrate both methods. A discussion and compansons between the two methods are given with the conclusions drown from the above study. 1- Heat transfer coefficient of the different arrangements with anther Sh/d and S/d for both in-line and staggered arrangements in the different fixed volumes.2- Heat transfer coefficient of enhanced tubes surface at the same conditions for both in-line and staggered arrangements in the same fixed volume.3- Optimum design of tube surface enhancement for both in-line and staggered arrangements .4- Study the effect of using hot and moist air on the heat transfer coefficient of the same different arrangements ( in-line and staggered) in the same fixed values.4-1 ConclusionsFrom the experimental results presented and discussed in the previous chapter, the following conclusions may be made :1- The heat transfer characteristics of tubes in fixed volume , bothfor staggered and in-line arrangements are better than those forsingle tube at the same conditions .2- Staggered arrangements of tubes in fixed volume gives better heat transfer coefficient compared with in line one and at the same conditions .3- The optimal tube spacing for different arrangements at is Sh /d and S/d = 1 at S/d = 1 , for both in-line and staggered arrangements.4- A correlation for in-line and staggered arrangements of the present data are developed. This correlation satisfactorily expresses the influences of Re, Pr, and cylinder spacing on the Nusselt Number Nu . The correlation can be used to predict the heat transfer coefficient with reasonable accuracy not exceeding ± 30% of measured values.4-2 Recommendations For Future WorkFrom the experimental study of heat transfer coefficient of single smooth tube, in-line and staggered arrangements of smooth tubes in a fixed volume , we recommend the following research points for the future work as follows:1- Heat transfer coefficient of the different arrangements with anther Sh/d and S/d for both in-line and staggered arrangements in the different fixed volumes.2- Heat transfer coefficient of enhanced tubes surface at the same conditions for both in-line and staggered arrangements in the same fixed volume.3- Optimum design of tube surface enhancement for both in-line and staggered arrangements .4- Study the effect of using hot and moist air on the heat transfer coefficient of the same different arrangements ( in-line and staggered) in the same fixed values.4-1 ConclusionsFrom the experimental results presented and discussed in the previous chapter, the following conclusions may be made :1- The heat transfer characteristics of tubes in fixed volume , bothfor staggered and in-line arrangements are better than those forsingle tube at the same conditions .2- Staggered arrangements of tubes in fixed volume gives better heat transfer coefficient compared with in line one and at the same conditions .3- The optimal tube spacing for different arrangements at is Sh /d and S/d = 1 at S/d = 1 , for both in-line and staggered arrangements.4- A correlation for in-line and staggered arrangements of the present data are developed. This correlation satisfactorily expresses the influences of Re, Pr, and cylinder spacing on the Nusselt Number Nu . The correlation can be used to predict the heat transfer coefficient with reasonable accuracy not exceeding ± 30% of measured values.4-2 Recommendations For Future WorkFrom the experimental study of heat transfer coefficient of single smooth tube, in-line and staggered arrangements of smooth tubes in a fixed volume , we recommend the following research points for the future work as follows:1- Heat transfer coefficient of the different arrangements with anther Sh/d and S/d for both in-line and staggered arrangements in the different fixed volumes.2- Heat transfer coefficient of enhanced tubes surface at the same conditions for both in-line and staggered arrangements in the same fixed volume.3- Optimum design of tube surface enhancement for both in-line and staggered arrangements .4- Study the effect of using hot and moist air on the heat transfer coefficient of the same different arrangements ( in-line and staggered) in the same fixed values.4-1 ConclusionsFrom the experimental results presented and discussed in the previous chapter, the following conclusions may be made :1- The heat transfer characteristics of tubes in fixed volume , bothfor staggered and in-line arrangements are better than those forsingle tube at the same conditions .2- Staggered arrangements of tubes in fixed volume gives better heat transfer coefficient compared with in line one and at the same conditions .3- The optimal tube spacing for different arrangements at is Sh /d and S/d = 1 at S/d = 1 , for both in-line and staggered arrangements.4- A correlation for in-line and staggered arrangements of the present data are developed. This correlation satisfactorily expresses the influences of Re, Pr, and cylinder spacing on the Nusselt Number Nu . The correlation can be used to predict the heat transfer coefficient with reasonable accuracy not exceeding ± 30% of measured values.4-2 Recommendations For Future WorkFrom the experimental study of heat transfer coefficient of single smooth tube, in-line and staggered arrangements of smooth tubes in a fixed volume , we recommend the following research points for the future work as follows:1- Heat transfer coefficient of the different arrangements with anther Sh/d and S/d for both in-line and staggered arrangements in the different fixed volumes.2- Heat transfer coefficient of enhanced tubes surface at the same conditions for both in-line and staggered arrangements in the same fixed volume.3- Optimum design of tube surface enhancement for both in-line and staggered arrangements .4- Study the effect of using hot and moist air on the heat transfer coefficient of the same different arrangements ( in-line and staggered) in the same fixed values.4-1 ConclusionsFrom the experimental results presented and discussed in the previous chapter, the following conclusions may be made :1- The heat transfer characteristics of tubes in fixed volume , bothfor staggered and in-line arrangements are better than those forsingle tube at the same conditions .2- Staggered arrangements of tubes in fixed volume gives better heat transfer coefficient compared with in line one and at the same conditions .3- The optimal tube spacing for different arrangements at is Sh /d and S/d = 1 at S/d = 1 , for both in-line and staggered arrangements.4- A correlation for in-line and staggered arrangements of the present data are developed. This correlation satisfactorily expresses the influences of Re, Pr, and cylinder spacing on the Nusselt Number Nu . The correlation can be used to predict the heat transfer coefficient with reasonable accuracy not exceeding ± 30% of measured values.4-2 Recommendations For Future WorkFrom the experimental study of heat transfer coefficient of single smooth tube, in-line and staggered arrangements of smooth tubes in a fixed volume , we recommend the following research points for the future work as follows:1- Heat transfer coefficient of the different arrangements with anther Sh/d and S/d for both in-line and staggered arrangements in the different fixed volumes.2- Heat transfer coefficient of enhanced tubes surface at the same conditions for both in-line and staggered arrangements in the same fixed volume.3- Optimum design of tube surface enhancement for both in-line and staggered arrangements .4- Study the effect of using hot and moist air on the heat transfer coefficient of the same different arrangements ( in-line and staggered) in the same fixed values.4-1 ConclusionsFrom the experimental results presented and discussed in the previous chapter, the following conclusions may be made :1- The heat transfer characteristics of tubes in fixed volume , bothfor staggered and in-line arrangements are better than those forsingle tube at the same conditions .2- Staggered arrangements of tubes in fixed volume gives better heat transfer coefficient compared with in line one and at the same conditions .3- The optimal tube spacing for different arrangements at is Sh /d and S/d = 1 at S/d = 1 , for both in-line and staggered arrangements.4- A correlation for in-line and staggered arrangements of the present data are developed. This correlation satisfactorily expresses the influences of Re, Pr, and cylinder spacing on the Nusselt Number Nu . The correlation can be used to predict the heat transfer coefficient with reasonable accuracy not exceeding ± 30% of measured values.4-2 Recommendations For Future WorkFrom the experimental study of heat transfer coefficient of single smooth tube, in-line and staggered arrangements of smooth tubes in a fixed volume , we recommend the following research points for the future work as follows:1- Heat transfer coefficient of the different arrangements with anther Sh/d and S/d for both in-line and staggered arrangements in the different fixed volumes.2- Heat transfer coefficient of enhanced tubes surface at the same conditions for both in-line and staggered arrangements in the same fixed volume.3- Optimum design of tube surface enhancement for both in-line and staggered arrangements .4- Study the effect of using hot and moist air on the heat transfer coefficient of the same different arrangements ( in-line and staggered) in the same fixed values.4-1 ConclusionsFrom the experimental results presented and discussed in the previous chapter, the following conclusions may be made :1- The heat transfer characteristics of tubes in fixed volume , bothfor staggered and in-line arrangements are better than those forsingle tube at the same conditions .2- Staggered arrangements of tubes in fixed volume gives better heat transfer coefficient compared with in line one and at the same conditions .3- The optimal tube spacing for different arrangements at is Sh /d and S/d = 1 at S/d = 1 , for both in-line and staggered arrangements.4- A correlation for in-line and staggered arrangements of the present data are developed. This correlation satisfactorily expresses the influences of Re, Pr, and cylinder spacing on the Nusselt Number Nu . The correlation can be used to predict the heat transfer coefficient with reasonable accuracy not exceeding ± 30% of measured values.4-2 Recommendations For Future WorkFrom the experimental study of heat transfer coefficient of single smooth tube, in-line and staggered arrangements of smooth tubes in a fixed volume , we recommend the following research points for the future work as follows:1- Heat transfer coefficient of the different arrangements with anther Sh/d and S/d for both in-line and staggered arrangements in the different fixed volumes.2- Heat transfer coefficient of enhanced tubes surface at the same conditions for both in-line and staggered arrangements in the same fixed volume.3- Optimum design of tube surface enhancement for both in-line and staggered arrangements .4- Study the effect of using hot and moist air on the heat transfer coefficient of the same different arrangements ( in-line and staggered) in the same fixed values.4-1 ConclusionsFrom the experimental results presented and discussed in the previous chapter, the following conclusions may be made :1- The heat transfer characteristics of tubes in fixed volume , bothfor staggered and in-line arrangements are better than those forsingle tube at the same conditions .2- Staggered arrangements of tubes in fixed volume gives better heat transfer coefficient compared with in line one and at the same conditions .3- The optimal tube spacing for different arrangements at is Sh /d and S/d = 1 at S/d = 1 , for both in-line and staggered arrangements.4- A correlation for in-line and staggered arrangements of the present data are developed. This correlation satisfactorily expresses the influences of Re, Pr, and cylinder spacing on the Nusselt Number Nu . The correlation can be used to predict the heat transfer coefficient with reasonable accuracy not exceeding ± 30% of measured values.4-2 Recommendations For Future WorkFrom the experimental study of heat transfer coefficient of single smooth tube, in-line and staggered arrangements of smooth tubes in a fixed volume , we recommend the following research points for the future work as follows:1- Heat transfer coefficient of the different arrangements with anther Sh/d and S/d for both in-line and staggered arrangements in the different fixed volumes.2- Heat transfer coefficient of enhanced tubes surface at the same conditions for both in-line and staggered arrangements in the same fixed volume.3- Optimum design of tube surface enhancement for both in-line and staggered arrangements .4- Study the effect of using hot and moist air on the heat transfer coefficient of the same different arrangements ( in-line and staggered) in the same fixed values.4-1 ConclusionsFrom the experimental results presented and discussed in the previous chapter, the following conclusions may be made :1- The heat transfer characteristics of tubes in fixed volume , bothfor staggered and in-line arrangements are better than those forsingle tube at the same conditions .2- Staggered arrangements of tubes in fixed volume gives better heat transfer coefficient compared with in line one and at the same conditions .3- The optimal tube spacing for different arrangements at is Sh /d and S/d = 1 at S/d = 1 , for both in-line and staggered arrangements.4- A correlation for in-line and staggered arrangements of the present data are developed. This correlation satisfactorily expresses the influences of Re, Pr, and cylinder spacing on the Nusselt Number Nu . The correlation can be used to predict the heat transfer coefficient with reasonable accuracy not exceeding ± 30% of measured values.4-2 Recommendations For Future WorkFrom the experimental study of heat transfer coefficient of single smooth tube, in-line and staggered arrangements of smooth tubes in a fixed volume , we recommend the following research points for the future work as follows:1- Heat transfer coefficient of the different arrangements with anther Sh/d and S/d for both in-line and staggered arrangements in the different fixed volumes.2- Heat transfer coefficient of enhanced tubes surface at the same conditions for both in-line and staggered arrangements in the same fixed volume.3- Optimum design of tube surface enhancement for both in-line and staggered arrangements .4- Study the effect of using hot and moist air on the heat transfer coefficient of the same different arrangements ( in-line and staggered) in the same fixed values.4-1 ConclusionsFrom the experimental results presented and discussed in the previous chapter, the following conclusions may be made :1- The heat transfer characteristics of tubes in fixed volume , bothfor staggered and in-line arrangements are better than those forsingle tube at the same conditions .2- Staggered arrangements of tubes in fixed volume gives better heat transfer coefficient compared with in line one and at the same conditions .3- The optimal tube spacing for different arrangements at is Sh /d and S/d = 1 at S/d = 1 , for both in-line and staggered arrangements.4- A correlation for in-line and staggered arrangements of the present data are developed. This correlation satisfactorily expresses the influences of Re, Pr, and cylinder spacing on the Nusselt Number Nu . The correlation can be used to predict the heat transfer coefficient with reasonable accuracy not exceeding ± 30% of measured values.4-2 Recommendations For Future WorkFrom the experimental study of heat transfer coefficient of single smooth tube, in-line and staggered arrangements of smooth tubes in a fixed volume , we recommend the following research points for the future work as follows:1- Heat transfer coefficient of the different arrangements with anther Sh/d and S/d for both in-line and staggered arrangements in the different fixed volumes.2- Heat transfer coefficient of enhanced tubes surface at the same conditions for both in-line and staggered arrangements in the same fixed volume.3- Optimum design of tube surface enhancement for both in-line and staggered arrangements .4- Study the effect of using hot and moist air on the heat transfer coefficient of the same different arrangements ( in-line and staggered) in the same fixed values.4-1 ConclusionsFrom the experimental results presented and discussed in the previous chapter, the following conclusions may be made :1- The heat transfer characteristics of tubes in fixed volume , bothfor staggered and in-line arrangements are better than those forsingle tube at the same conditions .2- Staggered arrangements of tubes in fixed volume gives better heat transfer coefficient compared with in line one and at the same conditions .3- The optimal tube spacing for different arrangements at is Sh /d and S/d = 1 at S/d = 1 , for both in-line and staggered arrangements.4- A correlation for in-line and staggered arrangements of the present data are developed. This correlation satisfactorily expresses the influences of Re, Pr, and cylinder spacing on the Nusselt Number Nu . The correlation can be used to predict the heat transfer coefficient with reasonable accuracy not exceeding ± 30% of measured values.4-2 Recommendations For Future WorkFrom the experimental study of heat transfer coefficient of single smooth tube, in-line and staggered arrangements of smooth tubes in a fixed volume , we recommend the following research points for the future work as follows:1- Heat transfer coefficient of the different arrangements with anther Sh/d and S/d for both in-line and staggered arrangements in the different fixed volumes.2- Heat transfer coefficient of enhanced tubes surface at the same conditions for both in-line and staggered arrangements in the same fixed volume.3- Optimum design of tube surface enhancement for both in-line and staggered arrangements .4- Study the effect of using hot and moist air on the heat transfer coefficient of the same different arrangements ( in-line and staggered) in the same fixed values.4-1 ConclusionsFrom the experimental results presented and discussed in the previous chapter, the following conclusions may be made :1- The heat transfer characteristics of tubes in fixed volume , bothfor staggered and in-line arrangements are better than those forsingle tube at the same conditions .2- Staggered arrangements of tubes in fixed volume gives better heat transfer coefficient compared with in line one and at the same conditions .3- The optimal tube spacing for different arrangements at is Sh /d and S/d = 1 at S/d = 1 , for both in-line and staggered arrangements.4- A correlation for in-line and staggered arrangements of the present data are developed. This correlation satisfactorily expresses the influences of Re, Pr, and cylinder spacing on the Nusselt Number Nu . The correlation can be used to predict the heat transfer coefficient with reasonable accuracy not exceeding ± 30% of measured values.4-2 Recommendations For Future WorkFrom the experimental study of heat transfer coefficient of single smooth tube, in-line and staggered arrangements of smooth tubes in a fixed volume , we recommend the following research points for the future work as follows:1- Heat transfer coefficient of the different arrangements with anther Sh/d and S/d for both in-line and staggered arrangements in the different fixed volumes.2- Heat transfer coefficient of enhanced tubes surface at the same conditions for both in-line and staggered arrangements in the same fixed volume.3- Optimum design of tube surface enhancement for both in-line and staggered arrangements .4- Study the effect of using hot and moist air on the heat transfer coefficient of the same different arrangements ( in-line and staggered) in the same fixed values.4-1 ConclusionsFrom the experimental results presented and discussed in the previous chapter, the following conclusions may be made :1- The heat transfer characteristics of tubes in fixed volume , bothfor staggered and in-line arrangements are better than those forsingle tube at the same conditions .2- Staggered arrangements of tubes in fixed volume gives better heat transfer coefficient compared with in line one and at the same conditions .3- The optimal tube spacing for different arrangements at is Sh /d and S/d = 1 at S/d = 1 , for both in-line and staggered arrangements.4- A correlation for in-line and staggered arrangements of the present data are developed. This correlation satisfactorily expresses the influences of Re, Pr, and cylinder spacing on the Nusselt Number Nu . The correlation can be used to predict the heat transfer coefficient with reasonable accuracy not exceeding ± 30% of measured values.4-2 Recommendations For Future WorkFrom the experimental study of heat transfer coefficient of single smooth tube, in-line and staggered arrangements of smooth tubes in a fixed volume , we recommend the following research points for the future work as follows:1- Heat transfer coefficient of the different arrangements with anther Sh/d and S/d for both in-line and staggered arrangements in the different fixed volumes.2- Heat transfer coefficient of enhanced tubes surface at the same conditions for both in-line and staggered arrangements in the same fixed volume.3- Optimum design of tube surface enhancement for both in-line and staggered arrangements .4- Study the effect of using hot and moist air on the heat transfer coefficient of the same different arrangements ( in-line and staggered) in the same fixed values.4-1 ConclusionsFrom the experimental results presented and discussed in the previous chapter, the following conclusions may be made :1- The heat transfer characteristics of tubes in fixed volume , bothfor staggered and in-line arrangements are better than those forsingle tube at the same conditions .2- Staggered arrangements of tubes in fixed volume gives better heat transfer coefficient compared with in line one and at the same conditions .3- The optimal tube spacing for different arrangements at is Sh /d and S/d = 1 at S/d = 1 , for both in-line and staggered arrangements.4- A correlation for in-line and staggered arrangements of the present data are developed. This correlation satisfactorily expresses the influences of Re, Pr, and cylinder spacing on the Nusselt Number Nu . The correlation can be used to predict the heat transfer coefficient with reasonable accuracy not exceeding ± 30% of measured values.4-2 Recommendations For Future WorkFrom the experimental study of heat transfer coefficient of single smooth tube, in-line and staggered arrangements of smooth tubes in a fixed volume , we recommend the following research points for the future work as follows:1- Heat transfer coefficient of the different arrangements with anther Sh/d and S/d for both in-line and staggered arrangements in the different fixed volumes.2- Heat transfer coefficient of enhanced tubes surface at the same conditions for both in-line and staggered arrangements in the same fixed volume.3- Optimum design of tube surface enhancement for both in-line and staggered arrangements .4- Study the effect of using hot and moist air on the heat transfer coefficient of the same different arrangements ( in-line and staggered) in the same fixed values.4-1 ConclusionsFrom the experimental results presented and discussed in the previous chapter, the following conclusions may be made :1- The heat transfer characteristics of tubes in fixed volume , bothfor staggered and in-line arrangements are better than those forsingle tube at the same conditions .2- Staggered arrangements of tubes in fixed volume gives better heat transfer coefficient compared with in line one and at the same conditions .3- The optimal tube spacing for different arrangements at is Sh /d and S/d = 1 at S/d = 1 , for both in-line and staggered arrangements.4- A correlation for in-line and staggered arrangements of the present data are developed. This correlation satisfactorily expresses the influences of Re, Pr, and cylinder spacing on the Nusselt Number Nu . The correlation can be used to predict the heat transfer coefficient with reasonable accuracy not exceeding ± 30% of measured values.4-2 Recommendations For Future WorkFrom the experimental study of heat transfer coefficient of single smooth tube, in-line and staggered arrangements of smooth tubes in a fixed volume , we recommend the following research points for the future work as follows:1- Heat transfer coefficient of the different arrangements with anther Sh/d and S/d for both in-line and staggered arrangements in the different fixed volumes.2- Heat transfer coefficient of enhanced tubes surface at the same conditions for both in-line and staggered arrangements in the same fixed volume.3- Optimum design of tube surface enhancement for both in-line and staggered arrangements .4- Study the effect of using hot and moist air on the heat transfer coefficient of the same different arrangements ( in-line and staggered) in the same fixed values.4-1 ConclusionsFrom the experimental results presented and discussed in the previous chapter, the following conclusions may be made :1- The heat transfer characteristics of tubes in fixed volume , bothfor staggered and in-line arrangements are better than those forsingle tube at the same conditions .2- Staggered arrangements of tubes in fixed volume gives better heat transfer coefficient compared with in line one and at the same conditions .3- The optimal tube spacing for different arrangements at is Sh /d and S/d = 1 at S/d = 1 , for both in-line and staggered arrangements.4- A correlation for in-line and staggered arrangements of the present data are developed. This correlation satisfactorily expresses the influences of Re, Pr, and cylinder spacing on the Nusselt Number Nu . The correlation can be used to predict the heat transfer coefficient with reasonable accuracy not exceeding ± 30% of measured values.4-2 Recommendations For Future WorkFrom the experimental study of heat transfer coefficient of single smooth tube, in-line and staggered arrangements of smooth tubes in a fixed volume , we recommend the following research points for the future work as follows:1- Heat transfer coefficient of the different arrangements with anther Sh/d and S/d for both in-line and staggered arrangements in the different fixed volumes.2- Heat transfer coefficient of enhanced tubes surface at the same conditions for both in-line and staggered arrangements in the same fixed volume.3- Optimum design of tube surface enhancement for both in-line and staggered arrangements .4- Study the effect of using hot and moist air on the heat transfer coefficient of the same different arrangements ( in-line and staggered) in the same fixed values.because the area involves an important industrial sector as well as a relaxing access toDamietta port the rest of the Delta..These results show important cost reductions that are analysed and comparedwith the main model.