Industrial Gas Engine Research Articles

Operational experience and new developments for industrial gas engines fuelled with hydrogen fuels

Since 2012 Horus-Energia has been developing the technology for the hydrogen fuelled industrial gas engines. First three units were commissioned in 2014 and in 2019 reached the forty thousand running hours milestone. The success of the first hydrogen project encouraged Horus-Energia to focus on further developments and improvements of the technology. Several R&D projects have been carried out since 2016 and resulted in two granted patents and another ones currently processed. The recent development project, carried out together with PGNiG Grupa Orlen, is in its final stage. The technology being developed creates a solid base for many new solutions that will cover wide range of fuels and applications. The paper reports experience from 40.000 hrs operation of the hydrogen fuelled industrial gas engines and presents the developments carried by Horus-Energia with its research partners as well as the future development paths for the technology.

Deformation mechanisms of low cycle fatigue of a fourth generation Ni-based single crystal superalloy

Ni-based single-crystal superalloys are extensively employed in turbine blades for aircraft and industrial gas engines. The blades are subjected to complex thermal and stress impacts during service, which may cause sudden low-cycle fatigue damage and subsequent flight accidents. To investigate the relationship between the microstructure and mechanical properties, fatigue-damaged microstructures are compared under cyclic deformation at 800 and 900 °C using combined electron microscope characterizations. With an increase in temperature, the deformation is more concentrated in the γ matrix channels and the cyclic deformation behaviors stabilizes, whereas cutting the γ′ phase becomes difficult with decreasing slip bands. In addition, the significance of interfacial dislocation networks in enhancing cyclic stability and hindering cyclic tension–compression asymmetry is discussed.

Stroke-dependent Coated Cylinder Liners for Large Industrial Gas Engines

Stroke-dependent Coated Cylinder Liners for Large Industrial Gas Engines

Regenerative Organic Rankine Cycle as Bottoming Cycle of an Industrial Gas Engine: Traditional and Advanced Exergetic Analysis

This investigation shows a traditional and advanced exergetic assessment of a waste heat recovery system based on recuperative ORC (organic Rankine cycle) as bottoming cycle of a 2 MW natural gas internal combustion engine. The advanced exergetic evaluation divides the study into two groups, the avoidable and unavoidable group and the endogenous and exogenous group. The first group provides information on the efficiency improvement potential of the components, and the second group determines the interaction between the components. A sensitivity analysis was achieved to assess the effect of condensing temperature, evaporator pinch, and pressure ratio with net power, thermal efficiencies, and exergetic efficiency for pentane, hexane, and octane as organic working fluids, where pentane obtained better energy and exergetic results. Furthermore, an advanced exergetic analysis showed that the components that had possibilities of improvement were the evaporator (19.14 kW) and the turbine (8.35 kW). Therefore, through the application of advanced exergetic analysis, strategies and opportunities for growth in the thermodynamic performance of the system can be identified through the avoidable percentage of destruction of exergy in components.

Fault Detection using Principal Component Analysis and Mean Value Modeling in a 2 MW gas engine

This paper describes the combination of statistical techniques and mathematical modeling in order to developed a fault detection system in a 2 MW natural gas engine under actual operation conditions. The Mixing chamber, turbochargers, intake and exhaust manifolds, cylinders, throttle and bypass valves, and the electric generator, which are the main components of the gas engine, were studied under a mean value engine to complement the statistical analysis. Objective: The main objective of this paper is to integrate two approaches in order to relate the faults with the changes of mean thermodynamic values of the system, helping to sustain the engine in optimal operating conditions in terms of reliability. The Principal Component Analysis (PCA), a multivariate statistical fault detection technique, was used to analyze the historical data from the gas engine to detect abnormal operation conditions, by means of statistical measures such as Square Prediction Error (SPE) and T2. These abnormal operation conditions are categorized using cluster techniques and contributions plots, to later examine its causes with the support of the results of a mean value mathematical model proposed for the system. The integration of the proposed methods allowed successfully identify which component or components of the engine might be malfunctioning. Once combined, these two methods were able to accurately predict and identify faults as well as shut downs of the gas engine during a month of operation. Statistical analysis was used to detect faults on a 2 MW industrial gas engine, also the result were compared with a mean value model in order to detect variations of the thermodynamic properties of the system at abnormal conditions.

The gas-air mixing systems for the industrial gas engine fuelled with low quality gas

Modifications of standard fuel system for an industrial gas engine and an analysis of the engine operation on low quality fuel have been described in this paper. The implemented fuel system modifications aim to overcome the challenges which arise when standard fuel gas is replaced by low quality one. Analysis focuses on stability of mixture formation esp. on variations in gas distribution for each cylinder of the engine. The results and discussion include also emissions optimization impact on efficiency as well as the efficiency and emissions level dependency on fuel type.

Effect of Cylindrical Turbulators on the Mixing Process in Basic Venturi Gas Mixer Using OpenFOAM

This study was devoted to improving the mixing quality in a Venturi gas mixer. It is well known that the performance of industrial gas engines strongly depends on the quality of air and fuel mixture and therefore on its homogeneity. Incorrect mixture proportions may lead to unstable operation of the entire industrial gas engine and excessive emissions exceeding environmental standards of the European Union. The effectiveness of the mixing process in a Venturi gas mixer depends on many factors, i.e. correct proportions between Air inlet, Venturi Throat diameter, as well as gas inlet area. To improve the intensification of the whole mixing process, as well as to increase the mixing time between gas and air, it was decided to insert disturbing elements in form of cylindrical turbulators into the Venturi pipe. Therefore numerical calculations were performed for the most commonly consumed by industrial gas engines lean Air-Fuel mixture, with an air excess coefficient ratio of λ = 1.6. In numerical analysis, OpenFOAM software was used to investigate the impact of cylindrical turbulators on the whole mixing process in a basic Venturi gas mixer. Particular attention was focused on the Air-Fuel Ratio (AFR) changes, Turbulent Kinetic Energy (TKE) and Pressure loss [Pa], which is one of the most qualitative evaluation parameters of a gas mixer.

Analysis of Combustion Process in Industrial Gas Engine with Prechamber-Based Ignition System

Application of a pre-combustion chamber (PCC) ignition system is one of the methods to improve combustion stability and reduce toxic compounds emission, especially NOx. Using PCC allows the operation of the engine at lean combustion conditions or the utilization of low calorific gaseous fuels such as syngas or biogas. The paper presents the results of an experimental study of the combustion process in two stroke, large bore, stationary gas engine GMVH 12 equipped with two spark plugs (2-SP) and a PCC ignition system. The experimental research has been performed during the normal operation of the engine in an industrial compression station. It was observed that application of PCC provides less cycle-to-cycle combustion variation (more than 10%) and nitric oxide and carbon monoxide emissions decreased to 60% and 26% respectively. The total hydrocarbon (THC) emission rate is 25% higher for the engine equipped with PCC, which results in roughly two percent engine efficiency decrease. Another important criterion of engine retrofitting was the PCC location in the engine head. The experimental results show that improvement of engine operating parameters was recorded only for a configuration with one port offset by 45° from the axis of the main chamber. The study of the ignition delay angle and equivalence ratio in PCC did not demonstrate explicit influence on engine performance.

Influence of gas inlet angle on the mixing process in a Venturi mixer

In this paper numerical analysis were performed to investigate the influence of gas inlet angle on mixing process in a Venturi mixer. Performance of an industrial gas engine depends significantly on the quality of mixing air and fuel; therefore, on the homogeneity of the mixture. In addition, there must be a suitable, adapted to the current load of fuel, air ratio. Responsible for this fact, among others, is the mixer located before entering the combustion chamber of the engine. Incorrect mixture proportion can lead to unstable operation of the engine, as well as higher emissions going beyond current environmental standards in the European Union. To validate the simulation the Air-Fuel Ratio (AFR) was mathematically calculated for the air-fuel mixture of lean combustion gas engine. In this study, an open source three-dimensional computational fluid dynamics (CFD) modelling software OpenFOAM has been used, to investigate and analyse the influence of different gas inlet angles on mixer characteristics and their performances. Attention was focused on the air-fuel ratio changes, pressure loss, as well as improvement of the mixing quality in the Venturi mixer.

Analysis of combustion process in industrial gas engines powered with high methane and nitrified low-calorific gases

The paper presents the results of an investigation of gas engines used in the Polish system of natural gas transmission. The investigation concerned both four-stroke and two-stroke engines. The engines were fed with two kinds of gas fuel – low-calorific natural gas containing 54.5 % of methane, and with high-methane (up to 95 %) natural gas. Combustion in both types of engines with different methods of mixture supply into the cylinder was analysed for different parameters. The paper also presents numerical computations of basic physical values characterizing combustion of gas fuels in engines. The computations were made with Cantera numerical code based on the mechanism of elementary reactions occurring while burning methane GRI 3.0 for various molar fractions of methane in the gas fuel.

High-temperature operation of a diode-pumped passively Q-switched Nd:YAG/Cr4+:YAG laser

The output performances of a diode-pumped Nd:YAG laser passively Q-switched by Cr4+:YAG saturable absorber crystal were investigated function of temperature. Increase of the temperature from 25 to 150°C increased slightly the laser pulse energy, and did not change the pulse duration. Furthermore, an increased absorbed energy of the pump radiation was necessary at temperatures higher than 25°C in order to maintain Q-switch operation. Measurements concluded that Cr4+:YAG transmission did not vary when temperature increased to 150°C. The decrease of Nd:YAG emission cross section with temperature and the changes of resonator configuration due to thermal effects were considered as main reasons for this behavior. The results of this work are valuable for designing a laser-ignition system for industrial gas engine or automotive industry.

Total least squares in fuzzy system identification: An application to an industrial engine

Takagi–Sugeno fuzzy models have proved to be a powerful tool for the identification of nonlinear dynamic systems. Their generic nonlinear model representation is particularly useful if information about the structure of the nonlinearity is available. In view of a practical applicability in industrial applications two important issues are addressed. First, the problem of unbiased estimation of local model parameters in the presence of input and output noise is considered. For that purpose the concept of total least squares for parameter estimation is reviewed and a related partitioning algorithm based on statistical criteria is presented. Second, the steady-state accuracy of dynamic models is addressed. A concept of constrained TLS parameter optimisation is introduced which enforces the adherence of the model to selected steady-state operating points and thus significantly improves the model accuracy during steady-state phases. Results from a simulation model and from an industrial gas engine power plant demonstrate the capabilities of the proposed concepts.

Precombustion Chamber NOx Emission Contribution to an Industrial Natural Gas Engine

This work expands the knowledge base concerning the formation of oxides of nitrogen (NO x) in the precombustion chamber (PCC) of a four-stroke lean burn (4SLB) industrial gas engine. Two analysis methods were used to characterize specific exhaust constituent concentrations formed in the PCC. The first method extracted gas from the PCC and the overall engine exhaust to be analysed by the industry standard five gas rack (THC, NO x, O 2, CO 2, and CO) and a Fourier transform infrared spectrometer (FTIR) to quantify formaldehyde (CH2O), nitric oxide (NO), and nitrogen dioxide (NO2) concentrations. This paper focuses only on NO x. The engine was operated at the manufacturer's recommended conditions and at the engine's lean limit. A PCC air-fuel ratio (A/F) map was performed at each engine operating condition by varying the fuel supply pressure to the PCC. An analytical model was developed to estimate the mass flow between the PCC and main cylinder, and mass flow out of the PCC through a sample extraction apparatus. The model was applied at specific instances during the engine cycle to clarify raw emissions data obtained directly from a cylinde's PCC. The model was developed to determine the origin of the mass sampled from the PCC which, in turn, was used to correct the measured pollutant concentrations. The corrected concentrations allowed for a comparison between NO x, emissions formed in the PCC and the overall engine exhaust on a mass specific basis. PCC-formed NO x, were found to constitute ε10 per cent while operating at the manufacture's recommended conditions and upwards of ε75 per cent when at the lean limit. The second test method utilized the high-speed chemiluminescence capabilities of a Cambustion fNOX400 analyser to measure NO concentration in gas extracted from the PCC on a half crank angle basis. The intra-cycle NO data were recorded simultaneously with pressure traces from the PCC and main cylinder by a Hi-Techniques combustion analysis system. The high-speed data acquisition system provided qualitative information on both intra-cycle NO concentrations and cycle-to-cycle variations.

エネルギー自由化時代における経営資源の選択と集中について

Osaka Gas has cultivated its core technologies through research and development based on a wealth of technological expertise accumulated since the days when gas was manufactured from coal. Research and development have been positioned as an important means for enhancing competitiveness in both the energy and non-energy businesses, and constant innovation has been pursued while maintaining speed and flexibility in its implementation. We are selective in the fields of R&D and are focusing on those areas that enhance the Osaka Gas Group's market position. Using our core technologies and product development capabilities, we aim to strengthen technological development capabilities that contribute to better safety, services, efficiency and sales in the energy business. In the gas business, Osaka Gas is advancing research and development that contributes to higher sales in gas operations, such as the commercialization of residential and industrial gas engine cogeneration systems, higher efficiency in cogeneration systems, and higher efficiency in gas heat pumps (GHP). In areas related to the electric power business, Osaka Gas is focusing efforts on the development of an electricity supply control system to comprehensively manage distributed power sources, including the power generation facilities of LNG terminals and cogeneration facilities installed at customers whose excess power is subject to retailing.