Wind load on irregular plan shaped tall building - a case study

Chakraborty, Souvik,Dalui, Sujit Kumar,Ahuja, Ashok Kumar Techno-Press 2014 Wind and Structures, An International Journal (WAS Vol.19 No.1

This paper presents the results of wind tunnel studies and numerical studies on a '+' plan shaped tall building. The experiment was carried out in an open circuit wind tunnel on a 1:300 scale rigid model. The mean wind pressure coefficients on all the surfaces were studied for wind incidence angle of $0^{\circ}$ and $45^{\circ}$. Certain faces were subjected to peculiar pressure distribution due to irregular formation of eddies caused by the separation of wind flow. Moreover, commercial CFD packages of ANSYS were used to demonstrate the flow pattern around the model and pressure distribution on various faces. k-${\varepsilon}$ and SST viscosity models were used for numerical study to simulate the wind flow. Although there are some differences on certain wall faces, the numerical result is having a good agreement with the experimental results for both wind incidence angle.

Wind load on irregular plan shaped tall building – a case study

Souvik Chakraborty,Sujit Kumar Dalui,Ashok Kuman Ahuja 한국풍공학회 2014 Wind and Structures, An International Journal (WAS Vol.19 No.1

This paper presents the results of wind tunnel studies and numerical studies on a '+' plan shaped tall building. The experiment was carried out in an open circuit wind tunnel on a 1:300 scale rigid model. The mean wind pressure coefficients on all the surfaces were studied for wind incidence angle of 0 and 45. Certain faces were subjected to peculiar pressure distribution due to irregular formation of eddies caused by the separation of wind flow. Moreover, commercial CFD packages of ANSYS were used to demonstrate the flow pattern around the model and pressure distribution on various faces. k-e and SST viscosity models were used for numerical study to simulate the wind flow. Although there are some differences on certain wall faces, the numerical result is having a good agreement with the experimental results for both wind incidence angle.

Impact of iron deficiency anemia on chronic periodontitis and superoxide dismutase activity: a cross-sectional study

Chakraborty, Souvik,Tewari, Shikha,Sharma, Rajinder Kumar,Narula, Satish Chander,Ghalaut, Pratap Singh,Ghalaut, Veena Korean Academy of Periodontology 2014 Journal of Periodontal & Implant Science Vol.44 No.2

Purpose: Both chronic periodontitis (CP) and iron deficiency anemia (IDA) induce oxidative stress in the body and cause an imbalance between reactive oxygen species and antioxidants, such as superoxide dismutase (SOD). This study explored the SOD enzyme activity of saliva and serum in CP patients with and without IDA and analyzed the impact of IDA on CP. Methods: A total of 82 patients were divided into four groups: control group (CG, 22), periodontally healthy IDA patients (IDA-PH, 20), CP patients (CP, 20), and IDA patients with CP (IDA-CP, 20). After clinical measurements and samplings, serum and salivary SOD levels were determined using an SOD assay kit. Results: IDA-CP patients exhibited a higher gingival index, bleeding on probing, probing pocket depth, and percentage (%) of sites with a clinical attachment loss (CAL) of ${\geq}6mm$ (P<0.008) than CP patients. The mean salivary and serum SOD levels were significantly lower in the IDA-PH, CP, and IDA-CP patients than in the CG group (P<0.008). A significant positive correlation between salivary and serum SOD activity was observed in IDA (P<0.05). Furthermore, serum and salivary SOD levels were significantly and negatively correlated with all periodontal parameters including the percentage of sites with CAL of 4-5 and ${\geq}6mm$ (P<0.05) except the significant correlation between salivary SOD activity and mean CAL and the percentage of sites with CAL of 4-5 mm (P>0.05) in these patients. Conclusions: Within the limits of this study, it may be suggested that IDA patients with chronic periodontitis have more periodontal breakdowns than patients with chronic periodontitis. Serum and salivary SOD activity levels were lower in the IDA-PH, CP and IDA-CP groups than in the CG. Iron deficiency anemia influenced the serum SOD activity but did not seem to affect the salivary SOD activity in these patients.

Impact of iron deficiency anemia on chronic periodontitis and superoxide dismutase activity: a cross-sectional study

Souvik Chakraborty,Shikha Tewari,Rajinder Kumar Sharma,Satish Chander Narula,Pratap Singh Ghalaut,Veena Ghalaut 대한치주과학회 2014 Journal of Periodontal & Implant Science Vol.44 No.2

Purpose: Both chronic periodontitis (CP) and iron deficiency anemia (IDA) induce oxidativestress in the body and cause an imbalance between reactive oxygen species and antioxidants,such as superoxide dismutase (SOD). This study explored the SOD enzyme activity ofsaliva and serum in CP patients with and without IDA and analyzed the impact of IDA on CP. Methods: A total of 82 patients were divided into four groups: control group (CG, 22), periodontallyhealthy IDA patients (IDA-PH, 20), CP patients (CP, 20), and IDA patients with CP(IDA-CP, 20). After clinical measurements and samplings, serum and salivary SOD levels weredetermined using an SOD assay kit. Results: IDA-CP patients exhibited a higher gingival index, bleeding on probing, probingpocket depth, and percentage (%) of sites with a clinical attachment loss (CAL) of ≥6 mm(P<0.008) than CP patients. The mean salivary and serum SOD levels were significantly lowerin the IDA-PH, CP, and IDA-CP patients than in the CG group (P<0.008). A significantpositive correlation between salivary and serum SOD activity was observed in IDA (P<0.05). Furthermore, serum and salivary SOD levels were significantly and negatively correlated withall periodontal parameters including the percentage of sites with CAL of 4–5 and ≥6 mm(P<0.05) except the significant correlation between salivary SOD activity and mean CAL andthe percentage of sites with CAL of 4–5 mm (P>0.05) in these patients. Conclusions: Within the limits of this study, it may be suggested that IDA patients withchronic periodontitis have more periodontal breakdowns than patients with chronic periodontitis. Serum and salivary SOD activity levels were lower in the IDA-PH, CP and IDA-CPgroups than in the CG. Iron deficiency anemia influenced the serum SOD activity but did notseem to affect the salivary SOD activity in these patients.

Wind induced pressure on 'Y' plan shape tall building

Mukherjee, Sourav,Chakraborty, Souvik,Dalui, Sujit Kumar,Ahuja, Ashok Kumar Techno-Press 2014 Wind and Structures, An International Journal (WAS Vol.19 No.5

This paper presents a comprehensive study of pressure developed on different faces of a 'Y' plan shape tall building using both numerical and experimental means. The experiment has been conducted in boundary layer wind tunnel located at Indian Institute of Technology Roorkee, India for flow condition corresponding to terrain category II of IS:875 (Part 3) - 1987, at a mean wind velocity of 10 m/s. Numerical study has been carried out under similar condition using computational fluid dynamics (CFD) package of ANSYS, namely ANSYS CFX. Two turbulence models, viz., $k-{\varepsilon}$ and Shear Stress Transport (SST) have been used. Good conformity among the numerical and experimental results have been observed with SST model yielding results of higher magnitude. Peculiar pressure distribution on certain faces has been observed due to interference effect. Furthermore, flow pattern around the model has also been studied to explain the phenomenon occurring around the model.

Wind induced pressure on 'Y' plan shape tall building

Sourav Mukherjee,Sujit Kumar Dalui,Souvik Chakraborty,Ashok Kumar Ahuja 한국풍공학회 2014 Wind and Structures, An International Journal (WAS Vol.19 No.5

This paper presents a comprehensive study of pressure developed on different faces of a 'Y' plan shape tall building using both numerical and experimental means. The experiment has been conducted in boundary layer wind tunnel located at Indian Institute of Technology Roorkee, India for flow condition corresponding to terrain category II of IS:875 (Part 3) – 1987, at a mean wind velocity of 10 m/s. Numerical study has been carried out under similar condition using computational fluid dynamics (CFD) package of ANSYS, namely ANSYS CFX. Two turbulence models, viz., k-ε and Shear Stress Transport (SST) have been used. Good conformity among the numerical and experimental results have been observed with SST model yielding results of higher magnitude. Peculiar pressure distribution on certain faces has been observed due to interference effect. Furthermore, flow pattern around the model has also been studied to explain the phenomenon occurring around the model.