Numerical study on the maneuvering of a container ship in shallow water waves Journal of Maritime Research, 2023
On the design of a compact emergency mechanical ventilator with negative expiratory exit pressure for COVID-19 patients Sheeja Janardhanan, Vidya Chandran, Rajesh Rajan Journal of Medical Engineering and Technology, 2023 The present work deals with the design of a cylinder-piston arrangement to deliver the required tidal volume (TV) of air to the patient through the respiratory tract especially in the setting of severe acute respiratory syndrome corona virus 2 (SARS CoV-2) or corona virus disease (COVID-19). The design ensures that only the desired volume of air is delivered in each breath and a negative pressure is retained at the delivery point in a separate cylinder. The frequency of piston motion is the same as that of the average human respiratory rate (RR). The effect of negative pressure on time of evacuation under the present condition has been verified. The present design provides a compact ventilator unit with a surface area of 0.8 × 0.4 m2 with a minimal power requirement of 116.48 W. An RR of 16 is obtained with a volume flow rate in lit/s by using a twin cylinder arrangement with bore diameter 0.1 m and length 0.4 m. The ratio of inspiration time to expiration time is designed to be 1:2 by controlling the stroke frequency as 16 and piston speed 0.32 m/s. The present design provides promising quantitative information on the design of an automated continuous mechanical ventilator (CMV), which is different from bag mask valve (BMV) operated ventilators, and on preventing and minimising barotrauma.
Numerical study on maneuvering a container ship in shallow water waves Premchand Mallampalli, Sheeja Janardhanan, Kesavadev Varikattu Karottu, Gnaneswar Ommi International Journal of Innovative Research and Scientific Studies, 2023 Numerous practical and mathematical techniques have been piloted to study ships’ behavior in deep water conditions with and without waves, and shallow water conditions without waves, while only limited investigations have been carried out to assess ships’ behavior in shallow waters with wave conditions as the flow around the stern region and appendages and the interaction effects are intricate. Therefore, this study attempts to understand the infrequently explored subset of a vessel’s behavior in regular waves in shallow water conditions (channel depth to ship draft ratio taken as 1.5). A container ship (S175) model scaled at 1:36 was the subject of a numerical study in which it was subjected to static and dynamic maneuver simulations in head sea conditions. The waves were induced using the dispersion relationship of waves in a given depth. The trends of forces and moments acting on the hull while undergoing maneuvering motions were obtained using a smooth particle hydrodynamics-based computational fluid dynamics solver. The resulting periodic trends of forces and moments were analyzed using the Fourier series method to extract the Fourier coefficients and, in turn, calculate the hydrodynamic derivatives. The trajectories in turning circle and zigzag maneuvers were also simulated using a MATLAB code. The results demonstrate an increase in trajectory parameters and improvement in counter maneuverability owing to the complex flow physics around the hull when encountering regular waves in shallow water conditions compared to waves in deep waters and a lack of waves in shallow waters.
A STUDY ON THE EFFECT OF SHIPPING POLLUTION IN THE PORT AND TERRITORIAL WATERS OF VISAKHAPATNAM Proceedings of the International Association of Maritime Universities Conference, 2023
Stability Derivatives of Various Lighter-than-Air Vehicles: A CFD-Based Comparative Study Anoop Sasidharan, Ratna Kishore Velamati, Sheeja Janardhanan, Venkata Ramana Murthy Oruganti, Akram Mohammad Drones, 2022 An aerostat with a single tether is proposed for the application of wind measurements at low altitudes. In the current study, the aerodynamic model parameters (stability derivatives) of the aerostat are investigated based on a CFD-based approach. The static, as well as the dynamic stability derivatives of the aerostats are presented. The calculation of the dynamic stability derivatives involves the simulation of the oscillations of the aerostats in their axial direction (surge), the vertical direction (heave) and angular motions with respect to the lateral direction (pitch). A forced sinusoidal oscillation is used for the simulation of the aerostat, and one stable period of oscillation is taken for the derivatives’ extraction. Four different aerostats are considered for the current study with four different angles of attack. The Zhiyuan aerostat, HAA aerostat, NPL aerostat and GNVR aerostat are the aerostats considered for this study. The stability derivative results obtained for the four aerostats are analyzed and compared with respect to their geometrical features. From the static aerodynamic characteristics, the Zhiyuan aerostat shows better performance than the other aerostats in terms of the lift–drag ratio. The dynamic stability derivatives of the Zhiyuan aerostat suggest its application as the proposed low-altitude wind measurement system.
MATHEMATICAL MODELING AND DESIGN OF A BARREL CAM BASED TRANSMISSION MECHANISM FOR UNINTERRUPTED ENERGY HARNESSING FROM VORTICES 21st Annual General Assembly Iamu Aga 2021 Proceedings of the International Association of Maritime Universities Iamu Conference, 2021
Preface Lecture Notes in Mechanical Engineering, 2020
Controllability studies on fish-shaped unmanned under water vehicle undergoing manoeuvring motions Sustainable Development and Innovations in Marine Technologies Proceedings of the 18th International Congress of the International Maritime Association of the Mediterranean Imam 2019, 2020
Towards the development of a bio-inspired shark-shaped unmanned underwater vehicle Sustainable Development and Innovations in Marine Technologies Proceedings of the 18th International Congress of the International Maritime Association of the Mediterranean Imam 2019, 2020
Numerical simulation of centrifugal casting for functionally graded metal-matrix composites International Journal of Mechanical Engineering and Technology, 2017
Maneuverability assessment of a container ship using steady RANS method Proceedings of the International Offshore and Polar Engineering Conference, 2014
Effect of environmental loads on the maneuverability of a tanker Rina Royal Institution of Naval Architects International Conference on Computational and Experimental Marine Hydrodynamics Marhy 2014, 2014
