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Thermal management is critical in vehicles due to impact on the comfort and safety of the occupants and the overall energy efficiency. Electric vehicles (EV) are particularly sensitive to this as customers may experience anxiety range. An improved efficiency has wider benefits on range and operational costs for customers. For the manufacturer, it represents a competitive advantage due to the higher revenue potentials. Additionally, the environmental impact of the vehicle through its life is reduced. Digital twins have gained attention in recent years for their capability to accelerate development while reducing development and testing costs within multiple industries. Certain applications have moved towards complete three-dimensional models whereas others have adopted reduced order model techniques or hybrid approaches that combine different modeling techniques.

In an electric vehicle, nevertheless, to say the primary component is the electric motor (e-motor). Understanding the thermal performance of the e-motor is paramount in ensuring the overall efficient functioning of the electric vehicle. Usually, the high-power e-motors are oil-cooled due to relatively high thermal loads. The e-motor thermal response is monitored under the extreme conditions like warm-up cycle allowing the vehicle to move in a circular track multiple-times. In this condition, the vehicle undergoes heavy lateral and longitudinal accelerations, the e-motor speed varies and the consequent thermal losses from the rotor and stator components also vary accordingly. Importantly, the cooling oil sloshes rigorously that effects the heat removal capacity of the oil. The advanced capabilities of Computational Fluid Dynamics (CFD) allow to virtually simulate the warm-up cycle and capture the extremely transient thermal response of the e-motor in the given conditions.

Passenger vehicles like bus tend to soak up heat when they are parked under open sky or in a parking lot. The temperatures inside the vehicle can get very high during daytime due to heating and reduce the thermal comfort levels. All three modes of heat transfer i.e., conduction, convection and radiation contribute to the heating process. Cool-down tests are performed to replicate this thermal behaviour and evaluate the time required for cooling the internal bus volume to comfortable temperatures. The phenomenon can also be analysed using CFD and accounts of numerous such studies is available, however most of the studies are limited to steady state analysis. In this study an effort has been made to develop a fast and reasonably accurate transient numerical method to predict thermal behaviour of the cool-down for a school bus cabin. Effects of all three modes of heating (conduction, convection and solar radiation) has been evaluated and the method has been validated using test data.

Optimization of cooling circuit for Electric Vehicle Thermal management is paramount in electric vehicles (EVs) to ensure optimal performance, battery longevity, and overall safety. This paper presents a novel approach to improving the efficiency of cooling systems in automotive passenger vehicles, focusing specifically on battery circuits and e-motor cooling. Current systems employ separate pumps, degassing tanks, valves, and numerous mechanical components, resulting in complex layouts and increased assembly efforts. The primary challenge with the existing setup lies in its complexity and the associated drawbacks, including heat energy loss, increased weight, and space constraints. Moreover, the traditional approach necessitates a significant number of components, leading to higher system costs and maintenance requirements. To address these challenges, this paper proposes an integrated cooling system where the pump, degassing tank, and valves are consolidated into a single housing.

A 3D numerical CFD model is developed to predict cell gas venting, threshold internal pressure and gas phase behavior of 18650 lithium cell during thermal runaway condition. The 4-equation thermal abuse model is used to model the gas phase reactions and venting mechanism inside the cell is modeled using Darcy’s equation. Present work is divided into two parts: 1) Venting gas Internal pressure prediction 2) modeling thermal runaway event. Both procedures are implemented on two different cell chemistries to understand and evaluate following parameters: Vent gas internal pressure, Flame propagation during thermal runaway, flame length comparison, total heat prediction and temperature of flame during thermal runaway event. Cell with NMC and LFP chemistries are modeled and compared at 100% SOC condition.

Hydrogen-powered mobility is believed to be crucial in the future, as hydrogen constitutes a promising solution to make up for the non-programmable character of the renewable energy sources. In this context, the hydrogen-fueled internal combustion engine represents one of the suitable technical solution for the future sustainable mobility. In a short-term perspective, the development of the green hydrogen production capability and distribution infrastructure do not allow a substantial penetration of pure hydrogen IC engines. For this reason, natural gas – hydrogen blends can represent a first significant step towards decarbonization, also determining a trigger effect on the hydrogen market development. The present paper is focused on the analysis of the combustion and performance characteristics of a production PFI natural gas engine, run on blends with 15% in volume of hydrogen (HCNG).

The global push to minimize carbon emissions and the imposition of more rigorous regulations on emissions are driving an increased exploration of cleaner powertrains for transportation. Hydrogen fuel applications in internal combustion engines are gaining prominence due to their zero carbon emissions and favorable combustion characteristics, particularly in terms of thermal efficiency. However, conventional Spark-Ignition (SI) engines are facing challenges in meeting performance expectations while complying with strict pollutant-emission regulations. These challenges arise from the engine's difficulty in handling advanced combustion strategies, such as lean mixtures, attributed to factors like low ignition energy and abnormal combustion events. To address these issues, the Barrier Discharge Igniter (BDI) stands out for its capability to generate non-equilibrium Low-Temperature Plasma (LTP), a strong promoter of ignition through kinetic, thermal, and transport effects.

In a context of growing concern for vehicle-related CO2 and pollutant emissions, non-conventional fuels like methanol (CH3OH) represent a valid alternative to fossil fuels to decarbonize the transport sector in a reasonable time. This is mainly due to its lower carbon content, compared to conventional gasoline and diesel. Moreover, methanol can be obtained either from biomass or CO2 capture from the atmosphere, which makes the latter a renewable fuel. Given the possibility of being stored in liquid phase at standard temperature and pressure (STP), methanol is very suitable for Light Duty Vehicles (LDVs), in which the need to contain fuel tank dimensions is relevant. Regarding the deployment of methanol as a fuel, it is not very challenging, as it can be adopted in current production Internal Combustion Engines (ICEs) either in pure form or in blend with other fuels without any significant modifications.

Ammonia, with its significant hydrogen content, offers a practical alternative to pure hydrogen in marine applications and is easier to store due to its higher volumetric energy density. While Ammonia's resistance to auto-ignition makes it suitable for high-compression ratio engines using pre-mixed charge, its low flame speed poses challenges. Innovative combustion strategies, such as dual-fuel and reactivity-controlled compression ignition (RCCI), leverage secondary high-reactivity fuels like diesel to enhance Ammonia combustion. To address the challenges posed by Ammonia's low flame speed, blending with hydrogen or natural gas (NG) in the low reactivity portion of the fuel mixture is an effective approach. For combustion simulation in engines, it is crucial to develop a chemical kinetics mechanism that accommodates all participating fuels: diesel, Ammonia, hydrogen, and NG. This study aims to propose a kinetics mechanism applicable for the combustion of these fuels together.

The lack of a homogeneous air-fuel mixture in internal combustion engines is a major cause of pollutant emissions, such as carbon monoxide (CO) and hydrocarbons (HC). This paper focuses on the design, simulation, and testing of a modified air intake pipe for a gas engine, incorporating deflectors to induce a swirl effect in the air-fuel mixture. To determine the optimal configuration for the deflectors and the diameter of the air intake pipe, several Computational Fluid Dynamics (CFD) simulations were conducted. The best results were then tested on a real gas engine. The primary objective of this study is to offer a solution for increasing the homogeneity level of the air-fuel mixture in gas engines, without requiring significant changes to engine components. In this case, achieving this goal involves only relatively small modifications to the air intake pipe.

The energy transition is a key challenge and opportunity for the transport sector. In this context, the adoption of electric vehicles (EVs) is emerging as a key solution to reduce environmental impact and mitigate problems related to traditional energy sources. One of the biggest problems related to electric mobility is the limited driving range it offers compared to the time needed for recharging, leading to what's commonly known as "range anxiety" among users. Significant part of the energy consumption of an electric vehicle is represented by the management of the HVAC system, which aim is to ensure the achievement and maintenance of thermal comfort conditions for the occupants of the vehicle.

Hydrogen engines are currently considered as a viable solution to preserve the internal combustion engine (ICE) as a power unit for vehicle propulsion. In particular, lean-burn gasoline Spark-Ignition (SI) engines have been a major subject of investigation, due to their reduced emission levels and high thermodynamic efficiency. Lean charge is suitable for passenger car applications, where the demand of mid/low power output does not require an excessive amount of air to be delivered by the turbocharging unit, but can difficulty be tailored in the field of high-performance engine, where the air mass delivered would require oversized turbocharging systems or more complex charging solutions. For this reason, the range of feeding conditions near the stochiometric is explored in the field of high-performance engines, leading to the consequent issue of abatement of pollutant emissions.

To further unlock the potential of methanol, this paper focuses on a dual injection concept in a spark ignition (SI) combustion engine. The combination of port fuel injection (PFI) and direct injection (DI) for different fuel types, as well as single and dual fuel applications, such as gasoline for PFI and methanol for DI, has been discussed in the literature. The consideration of a single-fuel dual injection concept with pure methanol is intended to provide information on the characteristics of each injection method and, by combining these, eliminate the disadvantages of one type with the advantages of the other. The research for sustainable alternative fuels for combustion engines was driven by the urgency to meet future emission regulation norms and mitigate climate change and dependency on fossil fuels.

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