<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>0035-001X</journal-id>
<journal-title><![CDATA[Revista mexicana de física]]></journal-title>
<abbrev-journal-title><![CDATA[Rev. mex. fis.]]></abbrev-journal-title>
<issn>0035-001X</issn>
<publisher>
<publisher-name><![CDATA[Sociedad Mexicana de Física]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0035-001X2003000100013</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Efficiency of a Curzon and Ahlborn engine with Dulong-Petit heat transfer law]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Ladino-Luna]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Instituto Politécnico Nacional Escuela Superior de Ingeniería Mecánica y Eléctrica Departamento de Ingeniería en Comunicaciones y Electrónica]]></institution>
<addr-line><![CDATA[México Distrito Federal]]></addr-line>
<country>México</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>00</month>
<year>2003</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>00</month>
<year>2003</year>
</pub-date>
<volume>49</volume>
<numero>1</numero>
<fpage>87</fpage>
<lpage>91</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0035-001X2003000100013&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0035-001X2003000100013&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0035-001X2003000100013&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[Using the maximization of the power output per cycle, the optimization of a thermal engine performing a Carnot-type cycle is considered. It is assumed that the heat transfer between the reservoirs and the engine occurs according to the Dulong and Petit's heat transfer law. It is found that the efficiency obtained with this heat transfer law can be written as a power series in the parameter &#955; ~ 1/(ln Vmax - ln Vmin), where Vmax and Vmin are the maximum volume and minimum volume spanned by the cycle, respectively. It is also shown that the calculated efficiency verifies the semi-sum property of the ecological efficiency.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[Se considera la optimización de una máquina térmica por medio de un ciclo tipo Carnot, usando la maximización de la potencia de salida en el ciclo. Se supone que la transferencia de calor entre los almacenes y la máquina se realiza de acuerdo con la ley de transferencia de calor de Dulong y Petit. Se encuentra que la eficiencia obtenida con esta ley de transferencia de calor, se puede escribir como una serie de potencias del parámetro &#955; ~ 1/(ln Vmax - ln Vmin), donde Vmax y Vmin son los volúmenes máximo y mínimo subtendidos por el ciclo, respectivamente. También se muestra que la eficiencia calculada cumple la propiedad de semi-suma de la eficiencia ecológica.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Finite time thermodynamics]]></kwd>
<kwd lng="en"><![CDATA[optimization]]></kwd>
<kwd lng="en"><![CDATA[power output]]></kwd>
<kwd lng="es"><![CDATA[Termodinámica de tiempos finitos]]></kwd>
<kwd lng="es"><![CDATA[optimización]]></kwd>
<kwd lng="es"><![CDATA[potencia de salida]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[  	    <p align="justify"><font face="verdana" size="4">Ense&ntilde;anza</font></p>      <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>  	    <p align="center"><font face="verdana" size="4"><b>Efficiency of a Curzon and Ahlborn engine with Dulong&#45;Petit heat transfer law</b></font></p>      <p align="center"><font face="verdana" size="2">&nbsp;</font></p>  	    <p align="center"><font face="verdana" size="2"><b>D. Ladino&#45;Luna*</b></font></p>  	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>  	    <p align="justify"><font face="verdana" size="2"><i>Depto. de ICE, ESIME&#45;IPN, U.P. Zacatenco, Edif. 4, Av. I.P.N. s/n Col. San Pedro Zacatenco, C.P. 07738, D.F., M&eacute;xico.</i></font></p>  	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>  	    <p align="justify"><font face="verdana" size="2">Recibido el 6 de marzo de 2002.    ]]></body>
<body><![CDATA[<br> 	Aceptado el 16 de julio de 2002.</font></p>  	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>  	    <p align="justify"><font face="verdana" size="2"><b>Abstract</b></font></p>  	    <p align="justify"><font face="verdana" size="2">Using the maximization of the power output per cycle, the optimization of a thermal engine performing a Carnot&#45;type cycle is considered. It is assumed that the heat transfer between the reservoirs and the engine occurs according to the Dulong and Petit's heat transfer law. It is found that the efficiency obtained with this heat transfer law can be written as a power series in the parameter <i>&#955; &#126;</i> 1/(ln <i>V<sub>max</sub> &#151;</i> ln <i>V<sub>min</sub></i>), where <i>V<sub>max</sub></i> and <i>V<sub>min</sub></i> are the maximum volume and minimum volume spanned by the cycle, respectively. It is also shown that the calculated efficiency verifies the semi&#45;sum property of the ecological efficiency.</font></p>  	    <p align="justify"><font face="verdana" size="2"><b>Keywords:</b> Finite time thermodynamics; optimization; power output.</font></p>  	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>  	    <p align="justify"><font face="verdana" size="2"><b>Resumen</b></font></p>  	    <p align="justify"><font face="verdana" size="2">Se considera la optimizaci&oacute;n de una m&aacute;quina t&eacute;rmica por medio de un ciclo tipo Carnot, usando la maximizaci&oacute;n de la potencia de salida en el ciclo. Se supone que la transferencia de calor entre los almacenes y la m&aacute;quina se realiza de acuerdo con la ley de transferencia de calor de Dulong y Petit. Se encuentra que la eficiencia obtenida con esta ley de transferencia de calor, se puede escribir como una serie de potencias del par&aacute;metro <i>&#955; &#126;</i> 1/(ln <i>V<sub>max</sub> &#151;</i> ln <i>V<sub>min</sub></i>), donde <i>V<sub>max</sub></i> y <i>V<sub>min</sub></i> son los vol&uacute;menes m&aacute;ximo y m&iacute;nimo subtendidos por el ciclo, respectivamente. Tambi&eacute;n se muestra que la eficiencia calculada cumple la propiedad de semi&#45;suma de la eficiencia ecol&oacute;gica.</font></p>  	    <p align="justify"><font face="verdana" size="2"><b>Descriptores:</b> Termodin&aacute;mica de tiempos finitos; optimizaci&oacute;n; potencia de salida.</font></p>  	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>  	    ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2">PACS: 44.6&#43;k; 44.90&#43;c</font></p>  	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>  	    <p align="justify"><font face="verdana" size="2"><a href="../pdf/rmf/v49n1/v49n1a13.pdf" target="_blank">DESCARGAR ART&Iacute;CULO EN FORMATO PDF</a></font></p>  	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><b>References</b></font></p>  	    <p align="justify"><font face="verdana" size="2">*. Also, Universidad Aut&oacute;noma Metropolitana&#45;Atzcapozalco.</font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">1.&nbsp;A. De Vos, <i>Endoreversible Thermodynamics of Solar Energy Conversion</i> (Oxford University Press, Oxford, 1992).    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8363793&pid=S0035-001X200300010001300001&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">2.&nbsp;H.B. Callen, <i>Thermodynamics and an Introduction to Thermo&#45;statistics</i> (Wiley, New York, 1985).    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8363795&pid=S0035-001X200300010001300002&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    ]]></body>
<body><![CDATA[<!-- ref --><p align="justify"><font face="verdana" size="2">3.&nbsp;F.L. Curzon and B. Ahlborn, <i>Am. J. Phys.,</i> <b>43</b> (1975) 22.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8363797&pid=S0035-001X200300010001300003&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">4.&nbsp;M.H. Rubin, <i>Phys. Rev.,</i> <b>A19</b> (1979) 1277.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8363799&pid=S0035-001X200300010001300004&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">5.&nbsp;J.L. Torres, <i>Rev. Mex. Fis.,</i> <b>34</b> (1988) 18.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8363801&pid=S0035-001X200300010001300005&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">6.&nbsp;M. Rubin and B. Andresen, <i>J. Appl. Phys.,</i> <b>53</b> (1982) 1.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8363803&pid=S0035-001X200300010001300006&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">7.&nbsp;F. Angulo&#45;Brown, <i>J. Appl. Phys.,</i> <b>69</b> (1991) 7465.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8363805&pid=S0035-001X200300010001300007&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    ]]></body>
<body><![CDATA[<!-- ref --><p align="justify"><font face="verdana" size="2">8.&nbsp;D. Gutkowics&#45;Krusin, I. Procaccia and J. Ross, <i>J. Chem. Phys.,</i> <b>69</b> (1978) 3898.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8363807&pid=S0035-001X200300010001300008&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">9.&nbsp;D. Ladino&#45;Luna and S.M.T. de la Selva, <i>Rev. Mex. F&iacute;s.,</i> <b>46</b> (2000) 52.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8363809&pid=S0035-001X200300010001300009&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">10.&nbsp;L.A. Arias&#45;Hern&aacute;ndez and F. Angulo&#45;Brown, <i>Rev. Mex. F&iacute;s.</i>, <b>40</b> (1994) 866.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8363811&pid=S0035-001X200300010001300010&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">11.&nbsp;F. Angulo&#45;Brown and R. P&aacute;ez&#45;Hern&aacute;ndez, <i>J. Appl. Phys.,</i> <b>74</b> (1993) 2216.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8363813&pid=S0035-001X200300010001300011&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">12.&nbsp;C.T. O'sullivan, <i>Am. J. Phys.,</i> <b>58</b> (1991) 956.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8363815&pid=S0035-001X200300010001300012&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     ]]></body>
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