Design and validation of a thermal management 1D simulation model for a high efficiency high performance powertrain.

Abstract

Over the past decades, a significant portion of powertrain research has been dedicated to exploring engine thermal management systems. The focus has been on enhancing system efficiency, reducing energy demand, and mitigating fluid-associated parasitic losses by controlling fluid temperatures and flow through a demand-oriented engine cooling system. The development of a robust 1D simulation model has been crucial for investigating and optimizing thermal management systems, with the goal of improving overall engine performance, reducing emissions, and extending engine life.
This work specifically delves into the creation of a 1D model for a V6 High-Performance Engine Cooling System, aiming to establish guidelines and methodologies for designing thermal management systems. The objective is to enhance engine performance, minimize fuel consumption, and optimize engine warm-up. The utilization of a mono-dimensional simulation model proves advantageous, significantly reducing simulation runtime compared to an "ideal" 3D CFD simulation model. From an engineering perspective, this approach facilitates early-stage project decision-making, providing a simpler simulation toolchain applicable for various purposes and resulting in time savings, reducing the costs of future engine development and helping to accelerate cleaner propulsion systems to market.
Furthermore, this research highlights its relevance to renewable fuels and diverse applications, encompassing emerging powertrain technologies such as hybrid electric vehicles (HEVs and PHEVs), electric vehicles (BEVs and FCEVs), hydrogen combustion engines, and mild hybrid systems. The developed thermal management system simulation tool is designed to accommodate these technologies, aiming to contribute to sustainable practices in both light and heavy-duty applications. The research underscores the versatility of these innovations, aligning with the broader objective of advancing eco-friendly solutions in powertrain engineering across a spectrum of automotive platforms.
In addressing the specific challenges posed by a power-dense V engine, the hydraulic modelling phase plays a pivotal role. The work introduces a revised approach to hydraulic modelling, particularly in treating the water jackets for a V6 engine. A primary challenge addressed is the balanced distribution of water mass flow rate between the two engine banks, ensuring improved mass flow rate distribution along the engine. This hydraulic technique is developed to accommodate different V engine geometries, enhancing the versatility of the model.
Additionally, the research outlines a comparison between lumped mass and finite element thermal modelling approach and a novel thermal calibration strategy that considers the unique aspects of power-dense V engines such as high power output, compact design weight consideration and performance. It validates this strategy using experimental thermal data obtained from an engine thermal survey. The calibration process incorporates a innovative approach, utilizing experimental engine metal temperature combined with a dedicated heat transfer multiplier for the engine block and head. This calibrated simulation model is then optimized, and the heat transfer multiplier is calculated for various engine operating points, to validate an engine thermal model.

Date of Award	17 Jan 2024
Original language	English
Awarding Institution	University of Bath
Supervisor	Sam Akehurst (Supervisor), Chris Brace (Supervisor) & Andrew Lewis (Supervisor)