Novel Hot Air Engine and Its Mathematical Model – Experimental Measurements and Numerical Analysis
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Abstract 1. Introduction 2. Robert Stirling
Stirling Stuff Dr John S. Reid, Department of Physics, Meston Building, University of Aberdeen, Aberdeen AB12 3UE, Scotland Abstract Robert Stirling’s patent for what was essentially a new type of engine to create work from heat was submitted in 1816. Its reception was underwhelming and although the idea was sporadically developed, it was eclipsed by the steam engine and, later, the internal combustion engine. Today, though, the environmentally favourable credentials of the Stirling engine principles are driving a resurgence of interest, with modern designs using modern materials. These themes are woven through a historically based narrative that introduces Robert Stirling and his background, a description of his patent and the principles behind his engine, and discusses the now popular model Stirling engines readily available. These topical models, or alternatives made ‘in house’, form a good platform for investigating some of the thermodynamics governing the performance of engines in general. ---------------------------------------------------------------------------------------------------------------- 1. Introduction 2016 marks the bicentenary of the submission of Robert Stirling’s patent that described heat exchangers and the technology of the Stirling engine. James Watt was still alive in 1816 and his steam engine was gaining a foothold in mines, in mills, in a few goods railways and even in pioneering ‘steamers’. Who needed another new engine from another Scot? The Stirling engine is a markedly different machine from either the earlier steam engine or the later internal combustion engine. For reasons to be explained, after a comparatively obscure two centuries the Stirling engine is attracting new interest, for it has environmentally friendly credentials for an engine. This tribute introduces the man, his patent, the engine and how it is realised in example models readily available on the internet. -
Feasibility Study Into Stirling Engines Application in Ship's Energy Systems
Transactions on the Built Environment vol 42, © 1999 WIT Press, www.witpress.com, ISSN 1743-3509 Feasibility study into Stirling engines application in ship's energy systems S. Zmudzki, Faculty of Maritime Technology, Technical University of Szczecin, 71- 065 Szczecin, al Piastow 41, Poland E-mail: szmudzkia@shiptech. tuniv.szczecin.pl Abstract The possibility of utilization of solar energy as well as exhaust gas energy from main and auxiliary marine diesel engines for driving Stirling engines has been analysed. The Stirling engines are used for driving current generators. The solar dish Stirling units of 100 kW total effective power may be installed on a board of different type of ships. The system utilizing the exhaust gas energy has been provided with three-way catalyst which may lead to the reduction of emissions below limits established by appropriate regulations. 1 Introduction The Stirling engine belongs to a group of piston engines with so called external supply of heat energy, flowing then through metal walls of engine heater into working gas circulating in the working space. The heat energy supply may be realized or by means of direct effect of the high temperature energy source or by an intermediate heating system i.e. heat pipe or pool-boiler receiver. Thus, the design provides for the possibility of application of different types of heat energy of sufficiently large power. In particular, the advantages of Stirling engines are set off when using the alternative energy sources, especially waste heat energy, the operating costs for which are relatively lower in comparison with capital costs. In case of ship s energy installations, the solar energy available at appropriate geographical latitudes for ships having very large open deck surface / i.e. -
Recording and Evaluating the Pv Diagram with CASSY
LD Heat Physics Thermodynamic cycle Leaflets P2.6.2.4 Hot-air engine: quantitative experiments The hot-air engine as a heat engine: Recording and evaluating the pV diagram with CASSY Objects of the experiment Recording the pV diagram for different heating voltages. Determining the mechanical work per revolution from the enclosed area. Principles The cycle of a heat engine is frequently represented as a closed curve in a pV diagram (p: pressure, V: volume). Here the mechanical work taken from the system is given by the en- closed area: W = − ͛ p ⋅ dV (I) The cycle of the hot-air engine is often described in an idealised form as a Stirling cycle (see Fig. 1), i.e., a succession of isochoric heating (a), isothermal expansion (b), isochoric cooling (c) and isothermal compression (d). This description, however, is a rough approximation because the working piston moves sinusoidally and therefore an isochoric change of state cannot be expected. In this experiment, the pV diagram is recorded with the computer-assisted data acquisition system CASSY for comparison with the real behaviour of the hot-air engine. A pressure sensor measures the pressure p in the cylinder and a displacement sensor measures the position s of the working piston, from which the volume V is calculated. The measured values are immediately displayed on the monitor in a pV diagram. Fig. 1 pV diagram of the Stirling cycle 0210-Wei 1 P2.6.2.4 LD Physics Leaflets Setup Apparatus The experimental setup is illustrated in Fig. 2. 1 hot-air engine . 388 182 1 U-core with yoke . -
Arxiv:2003.07157V1 [Cond-Mat.Stat-Mech] 10 Mar 2020 Oin Ti on Htteiiilvlmso H Odadho Engine
Stirling engine operating at low temperature difference Alejandro Romanelli∗ Instituto de F´ısica, Facultad de Ingenier´ıa Universidad de la Rep´ublica C.C. 30, C.P. 11000, Montevideo, Uruguay (Dated: March 17, 2020) Abstract The paper develops the dynamics and thermodynamics of Stirling engines that run with tem- perature differences below 100 0C. The working gas pressure is analytically expressed using an alternative thermodynamic cycle. The shaft dynamics is studied using its rotational equation of motion. It is found that the initial volumes of the cold and hot working gas play a non-negligible role in the functioning of the engine. arXiv:2003.07157v1 [cond-mat.stat-mech] 10 Mar 2020 1 I. INTRODUCTION In the field of energy efficiency, the use of waste energy is one of the keys to improve the performance of facilities, whether industrial or domestic. In general the waste energy arises as heat, from some thermal process, that it is necessary to remove. Therefore the use of the waste energy is usually conditioned by the difficulty of converting heat into other forms of energy.1,2 The Stirling engines, being external combustion machines, have the potential to take advantage of any source of thermal energy to convert it into mechanical energy. This makes them candidates to be used in heat recovery systems. The Stirling engine is essentially a two-part hot-air engine which operates in a closed regenerative thermodynamic cycle, with cyclic compressions and expansions of the working fluid at different temperature levels.3,4 The flow of the working fluid is controlled only by the internal volume changes; there are no valves and there is a net conversion of heat into work or vice-versa. -
Basic Thermodynamics-17ME33.Pdf
Module -1 Fundamental Concepts & Definitions & Work and Heat MODULE 1 Fundamental Concepts & Definitions Thermodynamics definition and scope, Microscopic and Macroscopic approaches. Some practical applications of engineering thermodynamic Systems, Characteristics of system boundary and control surface, examples. Thermodynamic properties; definition and units, intensive and extensive properties. Thermodynamic state, state point, state diagram, path and process, quasi-static process, cyclic and non-cyclic processes. Thermodynamic equilibrium; definition, mechanical equilibrium; diathermic wall, thermal equilibrium, chemical equilibrium, Zeroth law of thermodynamics, Temperature; concepts, scales, fixed points and measurements. Work and Heat Mechanics, definition of work and its limitations. Thermodynamic definition of work; examples, sign convention. Displacement work; as a part of a system boundary, as a whole of a system boundary, expressions for displacement work in various processes through p-v diagrams. Shaft work; Electrical work. Other types of work. Heat; definition, units and sign convention. 10 Hours 1st Hour Brain storming session on subject topics Thermodynamics definition and scope, Microscopic and Macroscopic approaches. Some practical applications of engineering thermodynamic Systems 2nd Hour Characteristics of system boundary and control surface, examples. Thermodynamic properties; definition and units, intensive and extensive properties. 3rd Hour Thermodynamic state, state point, state diagram, path and process, quasi-static -
Thermodynamics the Goal of Thermodynamics Is to Understand How Heat Can Be Converted to Work
Thermodynamics The goal of thermodynamics is to understand how heat can be converted to work Main lesson: Not all the heat energy can be converted to mechanical energy This is because heat energy comes with disorder (entropy), and overall disorder cannot decrease Temperature v T Random directions of velocity Higher temperature means higher velocities v Add up energy of all molecules: Internal Energy of gas U Mechanical energy: all atoms move in the same direction 1 Mv2 2 Statistical mechanics For one atom 1 1 1 1 1 1 3 E = mv2 + mv2 + mv2 = kT + kT + kT = kT h i h2 xi h2 yi h2 z i 2 2 2 2 Ideal gas: No Potential energy from attraction between atoms 3 U = NkT h i 2 v T Pressure v Pressure is caused because atoms T bounce off the wall Lx p − x px ∆px =2px 2L ∆t = x vx ∆p 2mv2 mv2 F = x = x = x ∆t 2Lx Lx ∆p 2mv2 mv2 F = x = x = x ∆t 2Lx Lx 1 mv2 =2 kT = kT h xi ⇥ 2 kT F = Lx Pressure v F kT 1 kT A = LyLz P = = = A Lx LyLz V NkT Many particles P = V Lx PV = NkT Volume V = LxLyLz Work Lx ∆V = A ∆Lx v A = LyLz Work done BY the gas ∆W = F ∆Lx We can write this as ∆W =(PA) ∆Lx = P ∆V This is useful because the body could have a generic shape Internal energy of gas decreases U U ∆W ! − Gas expands, work is done BY the gas P dW = P dV Work done is Area under curve V P Gas is pushed in, work is done ON the gas dW = P dV − Work done is negative of Area under curve V By convention, we use POSITIVE sign for work done BY the gas Getting work from Heat Gas expands, work is done BY the gas P dW = P dV V Volume in increases Internal energy decreases .. -
25 Kw Low-Temperature Stirling Engine for Heat Recovery, Solar, and Biomass Applications
25 kW Low-Temperature Stirling Engine for Heat Recovery, Solar, and Biomass Applications Lee SMITHa, Brian NUELa, Samuel P WEAVERa,*, Stefan BERKOWERa, Samuel C WEAVERb, Bill GROSSc aCool Energy, Inc, 5541 Central Avenue, Boulder CO 80301 bProton Power, Inc, 487 Sam Rayburn Parkway, Lenoir City TN 37771 cIdealab, 130 W. Union St, Pasadena CA 91103 *Corresponding author: [email protected] Keywords: Stirling engine, waste heat recovery, concentrating solar power, biomass power generation, low-temperature power generation, distributed generation ABSTRACT This paper covers the design, performance optimization, build, and test of a 25 kW Stirling engine that has demonstrated > 60% of the Carnot limit for thermal to electrical conversion efficiency at test conditions of 329 °C hot side temperature and 19 °C rejection temperature. These results were enabled by an engine design and construction that has minimal pressure drop in the gas flow path, thermal conduction losses that are limited by design, and which employs a novel rotary drive mechanism. Features of this engine design include high-surface- area heat exchangers, nitrogen as the working fluid, a single-acting alpha configuration, and a design target for operation between 150 °C and 400 °C. 1 1. INTRODUCTION Since 2006, Cool Energy, Inc. (CEI) has designed, fabricated, and tested five generations of low-temperature (150 °C to 400 °C) Stirling engines that drive internally integrated electric alternators. The fifth generation of engine built by Cool Energy is rated at 25 kW of electrical power output, and is trade-named the ThermoHeart® Engine. Sources of low-to-medium temperature thermal energy, such as internal combustion engine exhaust, industrial waste heat, flared gas, and small-scale solar heat, have relatively few methods available for conversion into more valuable electrical energy, and the thermal energy is usually wasted. -
A Stirling Engine for Automotive Applications Steve Djetel, Sylvie Bégot, François Lanzetta, Eric Gavignet, Wissam S
A Stirling Engine for Automotive Applications Steve Djetel, Sylvie Bégot, François Lanzetta, Eric Gavignet, Wissam S. Bou Nader To cite this version: Steve Djetel, Sylvie Bégot, François Lanzetta, Eric Gavignet, Wissam S. Bou Nader. A Stirling Engine for Automotive Applications. Vehicle Power and Propulsion Conference, Dec 2017, Belfort, France. hal-02131002 HAL Id: hal-02131002 https://hal.archives-ouvertes.fr/hal-02131002 Submitted on 16 May 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. A Stirling engine for automotive applications Steve Djetel, Sylvie Bégot, François Lanzetta, Wissam S. Bou Nader Eric Gavignet Technical center of Vélizy FEMTO-ST Institute PSA Group Univ. Bourgogne Franche-Comté, CNRS 78943 Velizy, France Département ENERGIE [email protected] 90000 Belfort, France [email protected] Abstract — This paper describes a Stirling Engine used as an the fuel and air are combusted under pressure and expanded Auxiliary Power Unit in a Series Hybrid Vehicle. The engine directly to produce work [4-5]. The Stirling technology is modeling is presented, then its integration in the vehicle power interesting for two major raisons: (1) the theoretical train is described. -
Comparison of ORC Turbine and Stirling Engine to Produce Electricity from Gasified Poultry Waste
Sustainability 2014, 6, 5714-5729; doi:10.3390/su6095714 OPEN ACCESS sustainability ISSN 2071-1050 www.mdpi.com/journal/sustainability Article Comparison of ORC Turbine and Stirling Engine to Produce Electricity from Gasified Poultry Waste Franco Cotana 1,†, Antonio Messineo 2,†, Alessandro Petrozzi 1,†,*, Valentina Coccia 1, Gianluca Cavalaglio 1 and Andrea Aquino 1 1 CRB, Centro di Ricerca sulle Biomasse, Via Duranti sn, 06125 Perugia, Italy; E-Mails: [email protected] (F.C.); [email protected] (V.C.); [email protected] (G.C.); [email protected] (A.A.) 2 Università degli Studi di Enna “Kore” Cittadella Universitaria, 94100 Enna, Italy; E-Mail: [email protected] † These authors contributed equally to this work. * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.: +39-075-585-3806; Fax: +39-075-515-3321. Received: 25 June 2014; in revised form: 5 August 2014 / Accepted: 12 August 2014 / Published: 28 August 2014 Abstract: The Biomass Research Centre, section of CIRIAF, has recently developed a biomass boiler (300 kW thermal powered), fed by the poultry manure collected in a nearby livestock. All the thermal requirements of the livestock will be covered by the heat produced by gas combustion in the gasifier boiler. Within the activities carried out by the research project ENERPOLL (Energy Valorization of Poultry Manure in a Thermal Power Plant), funded by the Italian Ministry of Agriculture and Forestry, this paper aims at studying an upgrade version of the existing thermal plant, investigating and analyzing the possible applications for electricity production recovering the exceeding thermal energy. A comparison of Organic Rankine Cycle turbines and Stirling engines, to produce electricity from gasified poultry waste, is proposed, evaluating technical and economic parameters, considering actual incentives on renewable produced electricity. -
And High Temperature Differential Stirling Engines
COMPARISON OF LOW- AND HIGH TEMPERATURE DIFFERENTIAL STIRLING ENGINES S. IWAMOTO*1, F. TODA*1, K. HIRATA*1 M. TAKEUCHI*2 and T. YAMAMOTO*3 *1Department of Mechanical Engineering, Faculty of Engineering, Saitama University, Japan *2Suction Gas Engine MFG. Co., Ltd., Japan *3National Institute for Research and Environment, Japan ABSTRACT Stirling engines can be operated with various heat sources. We have developed several Stirling engines, included a low temperature differential Stirling engine using hot spring heat and a high temperature differential Stirling engine using a combustion gas as the fuel. These engines have different features and characteristics, and have different thermal performance. In this paper, the performances of these difference types of Stirling engines were measured, were compared using the normalized values. INTRODUCTION In the field of the low temperature differential Stirling engines, several small Stirling engines have developed by I. Kolin, J. R. Senft and so on1),2). We have being developed the low temperature differential Stirling engine with several hundreds wattage of an output power3). The engine uses hot spring heat or hot water from industrial waste heat as the fuel. In this paper, we measured heat losses and powers of the engine in order to estimate the engine performance. Then the performance of a prototype of the low temperature differential Stirling engine (LDSE) was compared with that of a high temperature differential Stirling engine (HDSE) after their experimental results had been normalized. Figure 1 Feature of LDSE STRUCTURE OF LDSE Figure 1 and Fig. 2 show the features and structure of LDSE. Table 1 shows specifications of this engine and HDSE5) used to compare the performances. -
Supercritical CO 2 Cycles for Gas Turbine
Power Gen International December 8-10, Las Vegas, Nevada SUPERCRITICAL CO2 CYCLES FOR GAS TURBINE COMBINED CYCLE POWER PLANTS Timothy J. Held Chief Technology Officer Echogen Power Systems, LLC Akron, Ohio [email protected] ABSTRACT Supercritical carbon dioxide (sCO2) used as the working fluid in closed loop power conversion cycles offers significant advantages over steam and organic fluid based Rankine cycles. Echogen Power Systems LLC has developed several variants of sCO2 cycles that are optimized for bottoming and heat recovery applications. In contrast to cycles used in previous nuclear and CSP studies, these cycles are highly effective in extracting heat from a sensible thermal source such as gas turbine exhaust or industrial process waste heat, and then converting it to power. In this study, conceptual designs of sCO2 heat recovery systems are developed for gas turbine combined cycle (GTCC) power generation over a broad range of system sizes, ranging from distributed generation (~5MW) to utility scale (> 500MW). Advanced cycle simulation tools employing non-linear multivariate constrained optimization processes are combined with system and plant cost models to generate families of designs with different cycle topologies. The recently introduced EPS100 [1], the first commercial-scale sCO2 heat recovery engine, is used to validate the results of the cost and performance models. The results of the simulation process are shown as system installed cost as a function of power, which allows objective comparisons between different cycle architectures, and to other power generation technologies. Comparable system cost and performance studies for conventional steam-based GTCC are presented on the basis of GT-Pro™ simulations [2]. -
Removing the Mystery of Entropy and Thermodynamics – Part II Harvey S
Table IV. Example of audit of energy loss in collision (with a mass attached to the end of the spring). Removing the Mystery of Entropy and Thermodynamics – Part II Harvey S. Leff, Reed College, Portland, ORa,b Part II of this five-part series is focused on further clarification of entropy and thermodynamics. We emphasize that entropy is a state function with a numerical value for any substance in thermodynamic equilibrium with its surroundings. The inter- pretation of entropy as a “spreading function” is suggested by the Clausius algorithm. The Mayer-Joule principle is shown to be helpful in understanding entropy changes for pure work processes. Furthermore, the entropy change when a gas expands or is compressed, and when two gases are mixed, can be understood qualitatively in terms of spatial energy spreading. The question- answer format of Part I1 is continued, enumerating main results in Key Points 2.1-2.6. • What is the significance of entropy being a state Although the linear correlation in Fig. 1 is quite striking, the function? two points to be emphasized here are: (i) the entropy value In Part I, we showed that the entropy of a room temperature of each solid is dependent on the energy added to and stored solid can be calculated at standard temperature and pressure by it, and (ii) the amount of energy needed for the heating using heat capacity data from near absolute zero, denoted by T process from T = 0 + K to T = 298.15 K differs from solid to = 0+, to room temperature, Tf = 298.15 K.