scholarly journals Experimental Validation of a New Modeling for the Design Optimization of a Sliding Vane Rotary Expander Operating in an ORC-Based Power Unit

Energies ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 4204 ◽  
Author(s):  
Fabio Fatigati ◽  
Marco Di Bartolomeo ◽  
Davide Di Battista ◽  
Roberto Cipollone
Keyword(s):  
Design Optimization ◽  
Power Unit ◽  
Waste Heat ◽  
Combustion Engine ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Computational Time ◽  
Manufacturing Cost ◽  
External Diameter ◽  
New Model

Sliding Rotary Vane Expanders (SVRE) are often employed in Organic Rankine Cycle (ORC)-based power units for Waste Heat Recovery (WHR) in Internal Combustion Engine (ICE) due to their operating flexibility, robustness, and low manufacturing cost. In spite of the interest toward these promising machines, in literature, there is a lack of knowledge referable to the design and the optimization of SVRE: these machines are often rearranged reversing the operational behavior when they operate as compressors, resulting in low efficiencies and difficulty to manage off-design conditions, which are typical in ORC-based power units for WHR in ICE. In this paper, the authors presented a new model of the machine, which, thanks to some specific simplifications, can be used recursively to optimize the design. The model was characterized by a good level of physical representation and also by an acceptable computational time. Despite its simplicity, the model integrated a good capability to reproduce volumetric and mechanical efficiencies. The validation of the model was done using a wide experimental campaign conducted on a 1.5 kW SVRE operated on an ORC-based power unit fed by the exhaust gases of a 3 L supercharged diesel engine. Once validated, a design optimization was run, allowing to find the best solution between two “extreme” designs: a “disk-shaped”—increasing the external diameter of the machine and reducing axial length—and by a “finger-shaped” machine. The predictions of this new model were finally compared with a more complex numerical model, showing good agreement and opening the way to its use as a model-based control tool.

scholarly journals Development of a Pattern Recognition Methodology with Thermography and Implementation in an Experimental Study of a Boiler for a WHRS-ORC

2019 ◽  
Author(s):  
Concepción Paz ◽  
Eduardo Suarez ◽  
Miguel Concheiro ◽  
Antonio Diaz
Keyword(s):  
Pattern Recognition ◽  
Wall Temperature ◽  
Waste Heat ◽  
Combustion Engine ◽  
Organic Rankine Cycle ◽  
Exhaust System ◽  
Rankine Cycle ◽  
Operating Conditions ◽  
Cycle Performance ◽  
Working Fluid

Waste heat dissipated in the exhaust system in a combustion engine represents a major source of energy to be recovered and converted into useful work. A waste heat recovery system (WHRS) based on an Organic Rankine Cycle (ORC) is a promising approach, and has gained interest in the last few years in an automotive industry interested in reducing fuel consumption and exhaust emissions. Understanding the thermodynamic response of the boiler employed in an ORC plays an important role in steam cycle performance prediction and control system design. The aim of this study is therefore to present a methodology to study these devices by means of pattern recognition with infrared thermography. In addition, the experimental test bench and its operating conditions are described. The methodology proposed identifies the wall coordinates, traces paths, and tracks wall temperature along them in a way that can be exported for subsequent post-processing and analysis. As for the results, through the wall temperature paths on both sides (exhaust gas and working fluid) it was possible to quantitatively estimate the temperature evolution along the boiler and, in particular, the beginning and end of evaporation.

Modeling a Finned Tube Evaporator for Engine Exhaust Heat Recovery

2012 ◽  
Vol 229-231 ◽  
pp. 576-581
Author(s):  
En Hua Wang ◽  
Hong Guang Zhang ◽  
Bo Yuan Fan
Keyword(s):  
Diesel Engine ◽  
Waste Heat ◽  
Combustion Engine ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Finned Tube ◽  
Exhaust Temperature ◽  
Exhaust Heat ◽  
Heat Quantity ◽  
Power Point

The evaporator is a critical component when using organic Rankine cycle (ORC) to recover waste heat from an internal combustion engine. Evaluating the amount of heat quantity that can be transferred in a designed evaporator is very important for a successful ORC system. In this paper, a finned tube evaporator used for recovering the exhaust waste heat of a diesel engine was presented. The mathematical model for the evaporator was set up according to the dimensions of the designed evaporator along with the specified working conditions of ORC. The evaporator performance was analyzed as the matched diesel engine operating at the rated power point. The results indicate that the heat transfer quantity of the designed evaporator can be reached at 76 kW, and the exhaust temperature at the evaporator exit can be reduced to 115°C.

scholarly journals Development of a Pattern Recognition Methodology with Thermography and Implementation in an Experimental Study of a Boiler for a WHRS-ORC

Sensors ◽  
2019 ◽  
Vol 19 (7) ◽  
pp. 1680
Author(s):  
Concepción Paz ◽  
Eduardo Suárez ◽  
Miguel Concheiro ◽  
Antonio Diaz
Keyword(s):  
Pattern Recognition ◽  
Wall Temperature ◽  
Waste Heat ◽  
Combustion Engine ◽  
Organic Rankine Cycle ◽  
Exhaust System ◽  
Rankine Cycle ◽  
Operating Conditions ◽  
Cycle Performance ◽  
Working Fluid

Waste heat dissipated in the exhaust system in a combustion engine represents a major source of energy to be recovered and converted into useful work. A waste heat recovery system (WHRS) based on an Organic Rankine Cycle (ORC) is a promising approach, and it gained interest in the last few years in an automotive industry interested in reducing fuel consumption and exhaust emissions. Understanding the thermodynamic response of the boiler employed in an ORC plays an important role in steam cycle performance prediction and control system design. The aim of this study is, therefore, to present a methodology to study these devices by means of pattern recognition with infrared thermography. In addition, the experimental test bench and its operating conditions are described. The methodology proposed identifies the wall coordinates, traces the paths, and tracks the wall temperature along them in a way that can be exported for subsequent post-processing and analysis. As for the results, through the wall temperature paths on both sides (exhaust gas and working fluid), it was possible to quantitatively estimate the temperature evolution along the boiler and, in particular, the beginning and end of evaporation.

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

2020 ◽  
Vol 10 (13) ◽  
pp. 4411 ◽  
Author(s):  
Javier Cardenas Gutierrez ◽  
Guillermo Valencia Ochoa ◽  
Jorge Duarte-Forero
Keyword(s):  
Waste Heat ◽  
Combustion Engine ◽  
Pressure Ratio ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Waste Heat Recovery System ◽  
Improvement Potential ◽  
Recovery System ◽  
Analysis Strategies ◽  
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.

Review of Expander Selection for Small-Scale Organic Rankine Cycle

2014 ◽  
Author(s):  
Saeedeh Saghlatoun ◽  
Weilin Zhuge ◽  
Yangjun Zhang
Keyword(s):  
Internal Combustion Engines ◽  
Large Scale ◽  
Waste Heat ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Operating Conditions ◽  
Small Scale ◽  
Manufacturing Cost ◽  
Operating Characteristics ◽  
Small Scale Industries

After more than twenty years working on the selection of an appropriate expander for Organic Rankine cycles and wide research and attentions about its influence on the performance and total cost of waste heat recovery systems, now there is a good-enough background studies and achievement for large scale applications. But small-scale industries is like a art space to modify and revise the previous results. As it is clearly known, in small-scale applications and industries especially in internal combustion engines, besides the investigation of performance, physical properties and final efficiency of expander, other parameters should be analyzed accurately like manufacturing cost, availability, reliability, sensitivity to operating condition fluctuations. Due to a significant role of expander equipment to enhance the efficiency of ORC system in the first step expanders is investigated. In this paper, as per related operating characteristics, a complete comparison of small-scale expanders will be debated to guide designers to select more appropriate and the best efficient expansion machine as per their requirements. According to available literatures there is more need to do research about different types of expanders with various operating conditions in small-scale industries.

scholarly journals Thermoelectric Generation in Hybrid Electric Vehicles

Energies ◽  
2020 ◽  
Vol 13 (14) ◽  
pp. 3742
Author(s):  
Muhamad Shazrul bin Dzulkfli ◽  
Apostolos Pesyridis ◽  
Dhrumil Gohil
Keyword(s):  
Heat Recovery ◽  
Hybrid Electric Vehicle ◽  
Waste Heat Recovery ◽  
Engine Speed ◽  
Waste Heat ◽  
Combustion Engine ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Waste Heat Recovery System ◽  
Hybrid Electric

Improving the efficiency of an internal combustion engine (ICE) leads to the reduction of fuel consumption, which improves the performance of a hybrid vehicle. Waste heat recovery (WHR) systems offer options to improve the efficiency of an ICE. This is due to the ICE releasing approximately one third of the combustion energy as waste heat into the atmosphere. This paper focuses on one such upcoming system by analysing the efficiency of a thermoelectric generator (TEG) used as a waste heat recovery system in a hybrid electric vehicle (HEV). It summarises how the efficiency of the TEG can be improved by considering parameters such as the size of module, materials used, and the number of modules needed for the TEG system. The results obtained are then compared with other types of WHR system such as the Organic Rankine Cycle (ORC) and turbocompounding (T/C) implemented on the same type of engine. The research is based on a 1.8 L Toyota Prius-type engine. The TEG model simulated in this research can generate a maximum power of 1015 W at an engine speed of 5200 RPM. The overall system efficiency of TEG implemented on the HEV model is 6% with the average engine speed operating at 2000 RPM.

scholarly journals Expander Technologies for Automotive Engine Organic Rankine Cycle Applications

Energies ◽  
2018 ◽  
Vol 11 (7) ◽  
pp. 1905 ◽  
Author(s):  
Fuhaid Alshammari ◽  
Apostolos Karvountzis-Kontakiotis ◽  
Apostolos Pesyridis ◽  
Muhammad Usman
Keyword(s):  
Fuel Consumption ◽  
Heat Recovery ◽  
Waste Heat Recovery ◽  
Waste Heat ◽  
Combustion Engine ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Research Attention ◽  
Automotive Engine ◽  
Selection Of

The strive towards ever increasing automotive engine efficiencies for both diesel and gasoline engines has in recent years been forced by ever-stringent emissions regulations, as well as the introduction of fuel consumption regulations. The untapped availability of waste heat in the internal combustion engine (ICE) exhaust and coolant systems has become a very attractive focus of research attention by industry and academia alike. Even state of the art diesel engines operating at their optimum lose approximately 50% of their fuel energy in the form of heat. As a result, waste heat recovery (WHR) systems have gained popularity as they can deliver a reduction in fuel consumption and associated CO2 emissions. Of these, the Organic Rankine Cycle (ORC) is a well matured waste heat recovery technology that can be applied in vehicle powertrains, mainly due to the low additional exhaust backpressure on the engine and the potential opportunity to utilize various engine waste heat sources. ORCs have attracted high interest again recently but without commercial exploitation as of today due to the significant on-cost they represent to the engine and vehicle. In ORCs, expansion machines are the interface where useable power production takes place; therefore, selection of the expander technology is directly related to the thermal efficiency of the system. Moreover, the cost of the expander-generator units accounts for the largest proportion of the total cost. Therefore, selection of the most appropriate expander is of great importance at the early stage of any automotive powertrain project. This study aims to review the relevant research studies for expansion machines in ORC-ICE applications, analyzing the effects of specific speed on expander selection, exploring the operational characteristics of each expander to further assist in the selection of the most appropriate expander, and comparing the costs of various expanders based on publically available data and correlations.

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