Mohan Kumar Gajendran

Dr. Mohan Kumar Gajendran

orcid

Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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4 June 2021 in IEEE Access
Verified
Journal Article
Open access
MKMuhammad Zubair Khan
Muhammad Zubair Khan
MGMohan Kumar Gajendran
Mohan Kumar Gajendran
YLYugyung Lee
Yugyung Lee
MKMuazzam A. Khan
Muazzam A. Khan
Deep learning has an enormous impact on medical image analysis. Many computer-aided diagnostic systems equipped with deep networks are rapidly reducing human intervention in healthcare. Among several applications, medical image semantic segmentation is one of the core areas of active research to delineate the anatomical structures and other regions of interest. It has a significant contribution to healthcare and provides guided interventions, radiotherapy, and improved radiological diagnostics. The underlying article provides a brief overview of deep convolutional neural architecture, the platforms and applications of deep neural networks, metrics used for empirical evaluation, state-of-the-art semantic segmentation architectures based on a foundational convolution concept, and a review of publicly available medical image datasets highlighting four distinct regions of interest. The article also analyzes the existing work and provides open-ended potential research directions in deep medical image semantic segmentation.

Verified
Journal Article
Open access
PDF file
MGMohan Kumar Gajendran
Mohan Kumar Gajendran
IKIjaz Fazil Syed Ahmed Kabir
Ijaz Fazil Syed Ahmed Kabir
SVSudhakar Vadivelu
Sudhakar Vadivelu
Eddie YK NgEddie YK Ng
Eddie YK Ng
As wind energy continues to be a crucial part of sustainable power generation, the need for precise and efficient modeling of wind turbines, especially under yawed conditions, becomes increasingly significant. Addressing this, the current study introduces a machine learning-based symbolic regression approach for elucidating wake dynamics. Utilizing WindSE’s actuator line method (ALM) and Large Eddy Simulation (LES), we model an NREL 5-MW wind turbine under yaw conditions ranging from no yaw to 40 degrees. Leveraging a hold-out validation strategy, the model achieves robust hyper-parameter optimization, resulting in high predictive accuracy. While the model demonstrates remarkable precision in predicting wake deflection and velocity deficit at both the wake center and hub height, it shows a slight deviation at low downstream distances, which is less critical to our focus on large wind farm design. Nonetheless, our approach sets the stage for advancements in academic research and practical applications in the wind energy sector by providing an accurate and computationally efficient tool for wind farm optimization. This study establishes a new standard, filling a significant gap in the literature on the application of machine learning-based wake models for wind turbine yaw wake prediction.

6 October 2022 in Wind
Verified
Journal Article
Open access
PDF file
IKIjaz Fazil Syed Ahmed Kabir
Ijaz Fazil Syed Ahmed Kabir
MGMohan Kumar Gajendran
Mohan Kumar Gajendran
Eddie YK NgEddie YK Ng
Eddie YK Ng
AMAmirfarhang Mehdizadeh
Amirfarhang Mehdizadeh
Berrouk Abdallah S.Berrouk Abdallah S.
Berrouk Abdallah S.
Wind turbine blades experience excessive load due to inaccuracies in the prediction of aerodynamic loads by conventional methods during design, leading to structural failure. The blade element momentum (BEM) method is possibly the oldest and best-known design tool for evaluating the aerodynamic performance of wind turbine blades due to its simplicity and short processing time. As the turbine rotates, the aerofoil lift coefficient enhances, notably in the rotor’s inboard section, relative to the value predicted by 2D experimentation or computational fluid dynamics (CFD) for the identical angle of attack; this is induced by centrifugal pumping action and the Coriolis force, thus delaying the occurrence of stall. This rotational effect is regarded as having a significant influence on the rotor blade’s aerodynamic performance, which the BEM method does not capture, as it depends on 2D aerofoil characteristics. Correction models derived from the traditional hard computing mathematical method are used in the BEM predictions to take into account stall delay. Unfortunately, it has been observed from the earlier literature that these models either utterly fail or inaccurately predict the enhancement in lift coefficient due to stall delay. Consequently, this paper proposes a novel stall delay correction model based on the soft computing technique known as symbolic regression for high-level precise aerodynamic performance prediction by the BEM process. In complement to the correction model for the lift coefficient, a preliminary correction model for the drag coefficient is also suggested. The model is engendered from the disparity in 3D and 2D aerofoil coefficients over the blade length for different wind speeds for the NREL Phase VI turbine. The proposed model’s accuracy is evaluated by validating the 3D aerofoil coefficients computed from the experimental results of a second wind turbine known as the MEXICO rotor.

3 August 2024 in Atmosphere
Verified
Journal Article
Open access
PDF file
IKIjaz Fazil Syed Ahmed Kabir
Ijaz Fazil Syed Ahmed Kabir
MGMohan Kumar Gajendran
Mohan Kumar Gajendran
PTPrajna Manggala Putra Taslim
Prajna Manggala Putra Taslim
SBSethu Raman Boopathy
Sethu Raman Boopathy
Eddie YK NgEddie YK Ng
Eddie YK Ng
AMAmirfarhang Mehdizadeh
Amirfarhang Mehdizadeh
Renewable energy sources are essential to address climate change, fossil fuel depletion, and stringent environmental regulations in the subsequent decades. Horizontal-axis wind turbines (HAWTs) are particularly suited to meet this demand. However, their efficiency is affected by environmental factors because they operate in open areas. Adverse weather conditions like rain reduce their aerodynamic performance. This study investigates wind turbine power prediction under rainy conditions by integrating Blade Element Momentum (BEM) theory with explainable artificial intelligence (XAI). The S809 airfoil’s aerodynamic characteristics, used in NREL wind turbines, were analyzed using ANSYS FLUENT and symbolic regression under varying rain intensities. Simulations at a Reynolds number (Re) of 1 × 106 were performed using the Discrete Phase Model (DPM) and k–ω SST turbulence model, with liquid water content (LWC) values of 0 (dry), 10, 25, and 39 g/m3. The lift and drag coefficients were calculated at various angles of attack for all the conditions. The results indicated that rain led to reduced lift and increased drag. The innovative aspect of this research is the development of machine learning models predicting changes in the airfoil coefficients under rain with an R2 value of 0.97. The proposed XAI framework models rain effects at a lower computational time, enabling efficient wind farm performance assessment in rainy conditions compared to conventional CFD simulations. It was found that a heavy rain LWC of 39 g/m3 could reduce power output by 5.7% to 7%. These findings highlight the impact of rain on aerodynamic performance and the importance of advanced predictive models for optimizing renewable energy generation.

26 May 2023
Verified
Conference Paper
Closed access
MKM.A Khan
M.A Khan
MGMohan Kumar Gajendran
Mohan Kumar Gajendran
IKIjaz Fazil Syed Ahmed Kabir
Ijaz Fazil Syed Ahmed Kabir
SVS. Vadivelu
S. Vadivelu
Eddie YK NgEddie YK Ng
Eddie YK Ng
AMAmirfarhang Mehdizadeh
Amirfarhang Mehdizadeh
The escalating demand for energy, dwindling fossil fuel reserves, shifting fuel prices, and worries about climate change and pollution have prompted the investigation and assessment of renewable energy sources. Among these, wind power has emerged as a particularly promising candidate. However, due to limited suitable locations, wind turbines are often clustered together, necessitating the study of wake aerodynamics to optimize wind farm performance. Understanding and predicting wake characteristics that includes decreased velocity deficit and increased turbulence intensity are crucial for improving the efficiency of downstream turbines. Traditionally, low-fidelity models were used to predict wake characteristics, but recent advancements in computational fluid dynamics (CFD) have enabled more accurate predictions, albeit at the cost of increased computational time and resources. Machine learning (ML) has proven to be a valuable tool in addressing complex problems in various engineering domains, leading to the development of ML-based wake models that leverage CFD data for rapid predictions. However, these models have been limited by their reliance on a single wind turbine’s CFD results and their lack of generalizability to other turbines with different blade geometries and operating conditions. In response to these limitations, this study presents a novel wake prediction model using the symbolic regression technique. This innovative approach aims to offer precise aerodynamic performance predictions while maintaining simplicity, interpretability, and generalizability across various wind turbine designs. The proposed model holds significant potential for enhancing wind farm performance by accurately predicting wake characteristics and facilitating better decision-making in turbine placement and operation.