Search results for "natural ga"

An Effective Method to Model the Combustion Process in Spark Ignition Engines

2022

A numerical simulation is a fundamental tool in the design and optimization procedure of an Internal Combustion (IC) engine; since combustion is the process that mostly influences the engine performance, efficiency and emissions, an effective combustion submodel is fundamental. A simple, nonpredictive way to simulate the combustion evolution is to implement a mathematical function that reproduces the mass fraction burned (MFB) profile that is characterized by a sigmoidal trend; the most used for this purpose is the Wiebe function. In this article the authors propose a different mathematical model, a Dose-Response (DR) type function that shows some benefits when compared to the Wiebe functio…

Knock Resistance Increase through the Addition of Natural Gas or LPG to Gasoline: An Experimental Study

2013

Bi-fuel spark ignition engines, nowadays widely spread, are usually equipped with two independent injection systems, in order run the engine either with gasoline or with gaseous fuel, which can be Natural Gas (NG) or Liquefied Petroleum Gas (LPG). These gases, besides lower cost and environmental impact, are also characterized by a higher knock resistance with respect to gasoline that allows to adopt a stoichiometric proportion with air also at full load. Gasoline, on the other hand, being injected as liquid, maintains higher volumetric efficiency and hence higher power output. As a compromise solution, it could be desired to exploit the advantages of both gasoline and gas (NG or LPG), thus…

Urban Energy Hubs Economic Optimization and Environmental Comparison in Italy and Vietnam

2018

This paper aims to perform the minimization of the yearly energy supply cost from the main electricity and natural gas grids related to an energy district, considering the installation of different equipments. The case study refers to energy consumption of a medium density urban district and involves the exploitation of different energy sources and devices (photovoltaic systems, electrical energy storage, heat pumps and cogenerators). The analysis of the district energy supply is accomplished through an energy hub model. After a cost analysis related to the considered energy systems, a MILP algorithm was used for the optimization of a cost function and the simulation of various scenarios. M…

Performance Prevision of a Turbocharged Natural Gas Fuelled S.I. Engine

2008

Natural gas represents today maybe the most valid alternative to conventional fuels for road vehicles propulsion. The main constituent of natural gas, methane, is characterized by a high autoignition temperature, which makes the fuel highly resistant to knocking: this allows a considerable downsizing of the engine by means of supercharging even under high compression ratio. Starting from these considerations, the authors realized a thermodynamic model of a 4-cilynder s.i. engine for the prevision of in-cylinder pressure, employing a two-zone approach for the combustion and adding sub-models to account for gas properties change and knocking occurrence. An extensive experimental campaign has …

Detailed Combustion Analysis of a Supercharged Double-Fueled Spark Ignition Engine

2021

The main goal of researches in the field of automotive engineering is to obtain a large-scale implementation of low- or zero-emissions vehicles in order to substantially reduce air pollution in urban areas. A fundamental step toward this green transition is represented by the improvement of current internal combustion (IC) engines in terms of fuel economy and pollutant emissions. The spark ignition (SI) engines of modern light-duty vehicles are supercharged, down-sized, and equipped with direct injection. Gaseous fuels, such as liquefied petroleum gas (LPG) or natural gas (NG), proved to be a valid alternative to gasoline in order to reduce pollutant emissions and increase fuel economy. In …

Process analysis of a biomass-based quad-generation plant for combined power, heat, cooling, and synthetic natural gas production

2015

Abstract A new concept for upgrading distributed co-generation plants to quad-generation plants, which combine the production of power, heating, cooling and synthetic natural gas (SNG), is designed and analyzed. Five cases with SNG production ranging from 0% to 100% of total energy outputs are designed to simulate different modes of operation. The quad-generation system is simulated using ASPEN PLUS and described by simulating different portions of the system. This paper also describes the new process, which is of particular interest for improving the total first law efficiency. With this system, it is possible to increase the efficiency of natural resource utilization, minimize the environ…

Experimental analysis of the water retention behaviour of shales

2014

Shales are among the most commonly considered geomaterials in current energy-related geomechanical investigations, as they are involved in engineering applications such as the unconventional extraction of natural gas, CO2 sequestration and nuclear waste geological storage. A deep understanding of their behaviour with regard to variations in the degree of saturation is of primary significance for such applications. With the aim to establish a sound protocol for shale retention behaviour analysis, this paper presents an advanced experimental methodology that takes into account the specificities of shales such as small pore size dimensions and the large variations in water potential to be appl…

NATURAL GAS SUPPLY CHAIN: A SYSTEM AND PERFORMANCE ORIENTED APPROACH

Global energy consumption has been increasing in recent years. Among the main global energy sources, natural gas stands out. It presents benefits from diverse points of view, low emissions for the environment, low price for the consumers, lower cost and simplicity in the supply. That is why, within the global policies of emission reduction, natural gas is considered the source of transition energy between fossil fuels and clean, renewable and sustainable sources of energy. Considering that natural gas is a non-renewable resource, it presents a significant and progressive reduction in reserves in some regions worldwide, but with ample possibilities for the discovery of new reserves and trans…

Some aspects regarding natural gas and bibliometric networks

2021

In this paper, some aspects about natural gas, natural gas measurement, unauthorized interventions and stopping them were presented. A Scientometric study was conducted by querying the Web of Science database for the field of "natural gas". Based on the data obtained from Web of Science, the bibliometric relays were built using VOSviewer software. Bibliometric networks are useful for establishing the direction of research. The connections created in this software indicate your publications, magazines, researchers, the countries in which it was published, your interest in the subject of "natural gas" depending on the years. Product quality management and risk management proposes the elaborat…

Energy efficiency and CO2 emissions of port container terminal equipment: Evidence from the Port of Valencia

2019

Abstract Energy efficiency has emerged as a key point in port industry because of different factors such as the adoption of stronger environmental regulations and the increasing pressure of the local community on the surrounding ports. As gathering operational data from port terminals can be difficult due to privacy, studies on emissions and energy efficiency of these terminals are scarce. The following research provides key information about the real energy consumption and CO2 emissions of one of the most relevant container terminals in the Mediterranean area, located in Valencia, Spain. The results show that yard terminal tractors and rubber tyred gantry cranes (RTGs) are the main emissio…