Parnab Saha - Academia.edu (original) (raw)

Papers by Parnab Saha

Applied Thermal Engineering

Heat Transfer

In recent years, humidification and dehumidification (HDH) systems have garnered significant atte... more In recent years, humidification and dehumidification (HDH) systems have garnered significant attention due to their enhanced effectiveness with packed beds, particularly for high‐salinity waters. The direct‐contact packed beds HDH system offers a more convenient and efficient installation compared with conventional HDH systems. This paper introduces a novel, compact cylindrical crossflow HDH system design that is easily constructed and scalable for industrial and residential applications. The compact crossflow‐packed bed condenser employs perforated air tubes to distribute humidified air radially while cooling water drips vertically through the packed bed, coming into direct contact with the humidified air. To evaluate the system's performance, two‐dimensional steady‐state energy, and mass conservation equations were developed solving enthalpies instead of temperatures as dependents. The coupled partial differential equations were numerically solved to predict water temperature,...

Proceeding of 8th Thermal and Fluids Engineering Conference (TFEC)

Journal of Chemical Technology & Biotechnology, 2020

BACKGROUNDIn order to protect water resources and reduce the harmful effects of releasing contami... more BACKGROUNDIn order to protect water resources and reduce the harmful effects of releasing contaminated wastewater to the environment, the textile industry has increasingly demanded improved water reclamation technologies, such as membrane distillation. In this work, theoretical and experimental investigations were carried out to evaluate the behavior of the operational parameters of a direct contact membrane distillation (DCMD) setting with a commercial membrane applied to synthetic dye solutions, simulating textile wastewater from the fabric dyeing stage.RESULTSThe analytical model based on heat and mass transfer correlations specific to textile effluents implemented using Matlab® predicted the permeate flux with good agreement, with errors less than 10% when compared with the experimental values. There was a different trend for reactive and disperse dyes when input variables were changed. In general, increasing all variables led to an increase in permeate flux. An increase of 30 °...

Proceedings of the 2nd International Conference on Fluid Flow and Thermal Science (ICFFTS'21), 2021

A direct contact condenser with a packed bed is a highly efficient component of air/vapor mixture... more A direct contact condenser with a packed bed is a highly efficient component of air/vapor mixture condensation systems. A mathematical model is crucial to predict the performance of the condenser but existing models contain empirical correlations with limited or undefined range of validity. In this research, a comparison between several mass transfer coefficient correlations for air/vapor and liquid and the interfacial area is performed. An experimental setup has been built and tested for validation purposes. The boundary conditions and experimental data have been compared with the prediction from various listed models. It is concluded from the study that the Onda and Billet correlations are compatible with most of the results obtained from the experimental study.

2017 6th International Youth Conference on Energy (IYCE), 2017

the efficient and effective utilization of limited fossil fuel with a potential leverage from ren... more the efficient and effective utilization of limited fossil fuel with a potential leverage from renewable energy will certainly reduce the footprint and will improve the power generation process at the same time. Offshore covering two third of the world also a vast source of renewable energy is always a better location to place such hybrid plants especially for those well already bored at offshore. Such kind of plants will also reduce the risk of human loss in case of a disaster. Our work therefore, focuses on producing electricity in a floating power plant based on a recent discovery of gas in the Bay of Bengal. The objective is to design a hybrid floating gas turbine power plant, which will harness tidal and solar energy as well. Produced electricity can be added to the grid using submarine cable. A statistical analysis, coupled with simulated data will be presented to investigate the feasibility of such power plant. As Bangladesh, India and Myanmar surround the Bay of Bengal, surpassed electricity can be exported to neighboring countries. For countries like Bangladesh with high population density, this type of plants will eliminate the risk of pollution and the subsequent adverse effects on locality and surrounding wildlife.

The paper deals with the calculation of the performance of a marine propeller. For this the geome... more The paper deals with the calculation of the performance of a marine propeller. For this the geometrical characteristics and operating conditions have to be known. In order to analyze the marine propeller performance, the calculation of section lift co-efficient (CL) and section drag co-efficient (CD) of a particular blade section will develop a particular advance co-efficient, J which is required. This calculation is performed using Ansys Fluent Software. After Knowing CL ,CD, other section particulars are calculated by using propeller theories and then the corresponding thrust co-efficient (KT), torque co-efficient (KQ) as well as efficiency of different blade sections can be calculated. Finally after that overall performance of the propeller is calculated. Then the calculated results are compared with available experimental results.

International Journal of Sustainable Engineering, 2020

Earth pipe cooling (EPC) is a type of passive cooling system that takes advantage of the nearly c... more Earth pipe cooling (EPC) is a type of passive cooling system that takes advantage of the nearly constant underground temperature of the Earth to cool the atmospheric air in a confined space. The efficiency of this system depends on several factors, including the size and position of the inlet pipe, the velocity of the incoming air, shape of the cooling spaces and inlet surface pattern. However, ensuring uniform dispersion of the incoming cooled air can also improve the thermal comfort and efficiency of the EPC system, which has been overlooked in most of the existing studies. This paper, in this regard, presents a relevant parametric study to highlight that the efficiency of the EPC can be improved significantly by dispersing the oming flow through the proper utilisation of turbulators near the inlet. Thermal models are developed in ANSYS Fluent to perform this simulation-based study. It is found that the application of turbulators can help to reduce the domain temperature by around 0.8°C, thus saving an additional 0.84 kWh of energy per day for the particular cooling space considered in this study.

E3S Web of Conferences, 2018

Earth pipe cooling (EPC) is one of the passive cooling systems which has proven to be a very ener... more Earth pipe cooling (EPC) is one of the passive cooling systems which has proven to be a very energy efficient sustainable cooling technique for the sub-tropical areas. This cooling system uses the soil as a medium of heat transfer. Efficiency of this system largely depends on the velocity of the cooling air, shape of the cooling space, pattern of the walls in cooling space, inlet size and position of the incoming air. It is well-known that increasing the velocity of the cooling air will improve the efficiency of the cooling system. Therefore, this study focused on the optimization of the shape and pattern of the inlet which might improve the efficiency of the cooling system. ANSYS Fluent is used to perform this simulation-based study. It is found that inclusion of aerofoil shaped turbulator in the inlet cross sectional area provide better circulation of the air inside the cooling space, thus, enhance the effectiveness of the system.

Proceeding of 7th Thermal and Fluids Engineering Conference (TFEC)