CFD Analysis of Engine Room Temperature : CFD Analysis of Engine Room Temperature: Case study The Grange Castle Power Plant Project

Abstract: Computational Fluid Dynamics (CFD) has emerged as an indispensable tool in various engineering fields, particularly in the design and optimization of HVAC systems in complex environments, such as engine rooms. This paper presents a comprehensive overview of CFD applications and focuses on the engine rooms of the Grange Castle Power Plant in Dublin, Ireland. Sustainable Development Capital LLP (SDCL) is constructing a state-of-the-art power plant at Grange Castle Business Park in Dublin, featuring six MAN 18V51/60DF engine generators and a total net export capacity of 111 MW. The plant uses pioneering dualfuel technology and serves as a contingency facility to stabilize the power grid amidst increasing integration of renewable energy. It functions as a responsive backup power generator and a peak load reducer, aiding the Irish government's goal of sourcing 80% of power from renewables by 2030. The initiative is part of a wider strategy including MAN Energy Solutions and Greener Ideas Limited, contributing to three new power plants in Ireland with a combined capacity of 311 MW.This study utilizes steady-state CFD simulations, employing the widely adopted k-epsilon turbulence model. Known for its robustness and computational efficiency, the k-epsilon turbulence model is utilized to analyse one engine cell at the Grange Castle Power Plant. As a two-equation model, it involves solving two additional transport equations alongside the Navier-Stokes equations to simulate fluid flow.Commonly applied in engineering applications, this model will be utilized to provide predictions of airflow and temperatures within the cell during standby and running states over the course of the year. By leveraging the strengths of the k-epsilon turbulence model, the study seeks to gain valuable insights into the complex fluid dynamics within the engine cell, ultimately helping to optimize its performance and efficiency. The analysis focused on one engine cell, with the setup and geometry for each cell being identical.Specifically, the research investigates maintaining the temperature within the cell, temperature distributions, airflow comparisons to design specifications and requirements, heating load and adequate airflow calculations, and potential benefits of optimizing the design and operation of the engine cell.The dimensions and characteristics of the engine room, along with the engines themselves and the heat they generate, play a significant role in the design process. In this study, there are several essential factors to consider, including a negative pressure ventilation system, as well as combustion and cooling air provided through air intake units that draw air from outside the engine hall and exhaust it using fans mounted on the roof. The ventilation system must be designed to maintain the room temperature within the range of 9 °C to 45°C at different points in the room. Since the engine combustion air will be drawn from inside the engine hall, the ventilation system must provide the required volumes of combustion air at all times, along with the necessary ventilation. The CFD analysis conducted in this study provides the groundwork for designing an effective ventilation system that can maintain optimal temperature conditions in the engine room. Using the simulation results, the ventilation system will be optimized to ensure the required temperature is maintained while also preventing the formation of explosive atmospheres.iiAlso, the simulation study presented in this report showcases the ability of CFD simulations to predict airflow and temperature fields in the engine room of a power plant. It is essential to understand the different scenarios' conditions to design a reliable and efficient engine room system. Furthermore, CFD simulations have proven to be an effective tool for optimizing HVAC installations to meet specific building requirements even before installing any equipment. CFD takes into account all factors influencing airflow and temperature, ensuring finely tuned designs even in confined spaces.To accurately analyse and simulate the environment, a 3D model of the engine and room is created using Inventor and AutoCAD software. However, for complex systems like the engine room, simplifying the geometry is necessary when preparing a CFD model. This is because including every detail can result in an excessive number of mesh elements, leading to longer simulation times and higher computational costs. Therefore, striking a balance between geometric complexity and computational efficiency is important for an optimal CFD model. By creating a simplified model, the CFD simulation can be more computationally efficient while still accurately capturing important flow features. The 3D model allows for seamless integration with the CFD software, enabling accurate representation of the environment for analysis.The study conducted simulations for a high-power diesel & gas engine room under four different scenarios, covering various seasonal and load conditions. The results indicated that a heating coil with a 250 kW capacity is required to preheat the airflow of 25.5 m³/s by 8 °C to maintain the required temperature above 9 °C during winter. Similarly, during summer, fans with an airflow rate of 60 m³/s are necessary to keep the engine room temperature below 45 °C. This analysis is critical for designing an optimal ventilation system in engine rooms, ensuring sufficient airflow and maintaining appropriate engine temperature to prevent engine start failure. The simulation results provide invaluable information for HVAC engineers to design an efficient and reliable engine room system.Through the utilization of CFD simulations, engineers can simulate and analyse the performance of the HVAC system under various conditions, providing them with the necessary information to make well-informed decisions to ensure that the system meets the required performance criteria. Implementing CFD in the early stages of HVAC design provides valuable insights, saving engineers time and money associated with real-life testing and validation. By leveraging CFD simulations, engineers can virtually test and evaluate multiple design alternatives, ventilation strategies, and system configurations prior to actual implementation. This proactive approach helps engineers pinpoint potential issues, optimize system design for enhanced efficiency and effectiveness, and minimize the need for expensive post-installation modifications and adjustments.