Vehicle functional requirements, emission regulations, and thermal limits all have a direct impact on the design of a powertrain cooling airflow system. Given the expected increase in emission-related heat rejection, suppliers and vehicle manufacturers must work together as partners in the design, selection, and packaging of cooling system components. The goal of this two-day course is to introduce engineers and managers to the basic principles of cooling airflow systems for commercial and off-road vehicles.
Electric Vehicles are rapidly growing in the market yet various failure incidents were noted all along the globe. On the other hand, range anxiety has greatly inspired manufacturers to explore new practices to improve. One of the most important components of an EV is the battery, which converts chemical energy to electrical energy thereby liberating heat energy as the loss. This heat loss when high, capability of system to deliver required energy to wheels is reduced significantly. With a higher heat loss in the battery, system is prone to failure or reduced mileage. Therefore, controlling/maintaining system temperature under safe usable zone even during harsh conditions is ideal. Simple reduction in energy consumption of electrical cooling/heating devices used with regenerative energy techniques can greatly help in range improvement. The intention of this paper is to explore easy methods to improve electric vehicle range in different ambient conditions.
In order to meet stringent emission targets and to achieve better fuel efficiency, closed loop air mass control strategies have become essential across all vehicle segments. Closed loop air mass control mandates measuring fresh air mass entering the engine combustion chamber. However, in Naturally Aspirated (NA) engines, while measuring air mass using conventional methods such as Hot Film Air mass (HFM) sensor, heavy pulsations in the Air-intake results in errors which would impact closed loop air mass control and lead to inconsistencies in emissions. To address this issue, we studied different approaches using HFM sensor with Resonator, differential pressure sensor across the intake air filter and Lambda based air mass control. Based on this empirical study we found that modelling air mass with differential pressure sensor using Bernoulli’s principle (Flow rate ∝ √Differential pressure) results in higher accuracies compared to conventional methods.
Powertrain complexity rapidly increasing to meet fast moving regulation requirements. The BS6 Phase-1 regulation norms were implemented in India from April 1, 2020 and replaced the previous BS4 norms. Phase-2 of the BS6 regulation norms were came into effect on April 1, 2023. To meet this stringent regulation requirement, need effective performance of after treatment systems like DOC, DPF and SCR demands critical hardware selection and implementation. A robust DeNOx emissions strategy is developed in naturally aspirated single cylinder LCV application to meet cycle emissions, real drive emissions and OBD requirements. Naturally aspirated single cylinder engine has its own challenges to meet BS6 norms like higher engine out NOx, dynamic temperature profiles etc. It is always a challenge to adapt EATS in LCV application as these are low-cost vehicles. EATS components and sensors impacts the overall cost of the vehicle.
In Hydrogen internal combustion engines (H2ICE), the hydrogen is stored and operated at very low temperature before it enters the combustion chamber. The effect of hydrogen on steel materials is detrimental because of hydrogen embrittlement. Forged steel parts are used in engine specifically crankshafts, connecting rods, camshafts, and pistons. The objective of the work is to analyze the effect of low temperature i.e. 35 °C to -60 °C on three types of forged steel materials i.e. 40Cr4, 42CrMo4 and EN8 and assess any potential changes in their properties due to ductile brittle transition. The ductile to brittle transition charpy impact test is widely used to determine the temperature at which a material shifts from exhibiting ductile behavior to brittle behavior. This transition is critical for understanding the safety and reliability of steel components, as brittle fracture can lead to catastrophic failures.
The need for effective control systems is exacerbated by tighter pollution regulations. Also, there is growing demand for highly efficiently vehicles especially in the passenger segment. The air flow estimation of engine and accordingly controlling the fuel quantity removes many lacunas of the modern gasoline engines. The hot wire type mass air flow sensor is commonly used for air flow measurement, and is generally mounted in clean side piping to prevent damage to air mass flow sensor. The right estimation of air flow is possible by getting uniform flow over the different engine operating speed and load conditions. The placement of air flow sensor becomes critical considering the engine layout and packaging constraints and meeting the sensor mounting requirements. The deviation in mounting of air flow sensor will lead to consequential impact on engine performance and emissions.
Transmission adapter is solid, located on cylinder block , on which sits the transmission housing. The function of a flexplate is to provide a mounting point for a torque converter which is used to couple the engine and transmission together when an automatic transmission is used. Transmission adapter provide access for torque convertor and flexplate assembly and protect the flexplate from external environment. Transmission adapter is also support and locate the starter. This study deals with different alloy grade material use, improvement in process to reduce porosity. Porosity observed in first samples of the proposed grade material. The study represents investigation of Transmission adaptor porosity root cause. This also included visual observation, radiography -X ray testing , analysis,3D scan, dimensional inspection, chemical analysis and comparison, tensile testing, truck testing validation tasks.
Exhaust manifold in engine is used to transfer the hot exhaust gas from cylinder head to the turbocharger with minimum pressure loss and to support the turbocharger assembly. This puts manifold under intense thermal and mechanical loading and makes the design very complex. While designing the manifold, resonance of the system must be avoided, and thermo-mechanical fatigue life expectations must be met. Different engine applications would call for multiple turbocharger configuration and orientations to be considered in the design layout for system level resonance assessment. This paper talks about the failure investigation of the manifold which was designed for High mount rear out (HMRO) turbo orientation and then used with high mount front out (HMFO) layout in road miller application resulted into the manifold failures.