9.3: Apéndice C- Resumen de Ecuaciones de Conservación y Contabilidad, Conversiones de Unidades, Modelos de Propiedades, Datos de Propiedades Termofísicas
- Page ID
- 86266
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\(\newcommand{\avec}{\mathbf a}\) \(\newcommand{\bvec}{\mathbf b}\) \(\newcommand{\cvec}{\mathbf c}\) \(\newcommand{\dvec}{\mathbf d}\) \(\newcommand{\dtil}{\widetilde{\mathbf d}}\) \(\newcommand{\evec}{\mathbf e}\) \(\newcommand{\fvec}{\mathbf f}\) \(\newcommand{\nvec}{\mathbf n}\) \(\newcommand{\pvec}{\mathbf p}\) \(\newcommand{\qvec}{\mathbf q}\) \(\newcommand{\svec}{\mathbf s}\) \(\newcommand{\tvec}{\mathbf t}\) \(\newcommand{\uvec}{\mathbf u}\) \(\newcommand{\vvec}{\mathbf v}\) \(\newcommand{\wvec}{\mathbf w}\) \(\newcommand{\xvec}{\mathbf x}\) \(\newcommand{\yvec}{\mathbf y}\) \(\newcommand{\zvec}{\mathbf z}\) \(\newcommand{\rvec}{\mathbf r}\) \(\newcommand{\mvec}{\mathbf m}\) \(\newcommand{\zerovec}{\mathbf 0}\) \(\newcommand{\onevec}{\mathbf 1}\) \(\newcommand{\real}{\mathbb R}\) \(\newcommand{\twovec}[2]{\left[\begin{array}{r}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\ctwovec}[2]{\left[\begin{array}{c}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\threevec}[3]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\cthreevec}[3]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\fourvec}[4]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\cfourvec}[4]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\fivevec}[5]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\cfivevec}[5]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\mattwo}[4]{\left[\begin{array}{rr}#1 \amp #2 \\ #3 \amp #4 \\ \end{array}\right]}\) \(\newcommand{\laspan}[1]{\text{Span}\{#1\}}\) \(\newcommand{\bcal}{\cal B}\) \(\newcommand{\ccal}{\cal C}\) \(\newcommand{\scal}{\cal S}\) \(\newcommand{\wcal}{\cal W}\) \(\newcommand{\ecal}{\cal E}\) \(\newcommand{\coords}[2]{\left\{#1\right\}_{#2}}\) \(\newcommand{\gray}[1]{\color{gray}{#1}}\) \(\newcommand{\lgray}[1]{\color{lightgray}{#1}}\) \(\newcommand{\rank}{\operatorname{rank}}\) \(\newcommand{\row}{\text{Row}}\) \(\newcommand{\col}{\text{Col}}\) \(\renewcommand{\row}{\text{Row}}\) \(\newcommand{\nul}{\text{Nul}}\) \(\newcommand{\var}{\text{Var}}\) \(\newcommand{\corr}{\text{corr}}\) \(\newcommand{\len}[1]{\left|#1\right|}\) \(\newcommand{\bbar}{\overline{\bvec}}\) \(\newcommand{\bhat}{\widehat{\bvec}}\) \(\newcommand{\bperp}{\bvec^\perp}\) \(\newcommand{\xhat}{\widehat{\xvec}}\) \(\newcommand{\vhat}{\widehat{\vvec}}\) \(\newcommand{\uhat}{\widehat{\uvec}}\) \(\newcommand{\what}{\widehat{\wvec}}\) \(\newcommand{\Sighat}{\widehat{\Sigma}}\) \(\newcommand{\lt}{<}\) \(\newcommand{\gt}{>}\) \(\newcommand{\amp}{&}\) \(\definecolor{fillinmathshade}{gray}{0.9}\)C.1: Ecuaciones Básicas de Conservación y Contabilidad
Ecuaciones Básicas de Conservación y Contabilidad | |
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Ecuación contable para la propiedad genérica y extensa\(B\) : Propiedad Extensa —\(\displaystyle B_{sys} (t) = \iiint\limits_{V_{sys}} b_{(x, y, z, t)} \rho_{(x, y, z, t)} dV\) Ecuación Contable —\(\dfrac{dB_{sys} (t)}{dt} = \dot{B}_{in} - \dot{B}_{out} + \dot{B}_{gen} - \dot{B}_{cons}\) \[\underbrace{\frac{d B_{sys}}{d t}}_{\text {Accumulation}} = \underbrace{ \underbrace{\left\{\dot{B}_{in}-\dot{B}_{out}\right\}}_{\text {non-flow boundaries}} + \underbrace{\left\{\sum_{in} \dot{m}_{i} b_{i}-\sum_{out} \dot{m}_{e} b_{e}\right\}}_{\text {flow boundaries}} }_{\text {Transport}} + \underbrace{\left\{\dot{B}_{\text {gen}} - \dot{B}_{\text {cons}}\right\}}_{\text {Generation/Consumption}} \nonumber \] |
Conservación del Momentum Lineal:\(\displaystyle \quad \mathbf{P}_{sys} = \int\limits_{V_{sys}} \mathbf{V} \rho \ dV\) \[\frac{d \mathbf{P}_{sys}}{dt} = \sum_{j} \mathbf{F}_{\text{ext, } j} + \left\{\sum_{in} \dot{m}_{i} \mathbf{V}_{i} - \sum_{out} \dot{m}_{e} \mathbf{V}_{e} \right\} \nonumber \] |
Conservación de la Masa:\(\displaystyle \quad m_{sys} (t)=\iiint\limits_{V_{sys}} \rho_{(x, y, z, t)} \ d V\) \[\frac{d m_{sys}}{dt} = \sum_{in} \dot{m}_{i} - \sum_{out} \dot{m}_{e} \nonumber \] \[\text{where } \dot{m} = \int\limits_{A_C} \rho V_{n} \ dA_{C} = \underbrace{\rho A_{C} V_{\text{avg}}}_{\text{1-D Flow Assumption}} \quad \text{(the mass flow rate)} \nonumber \] |
Conservación del Momentum Angular:\(\displaystyle \quad \mathbf{L}_{o, \ sys} = \int\limits_{V_{sys}} (\mathbf{r} \times \mathbf{V}) \rho \ dV\) \[\frac{d \mathbf{L}_{o, \ sys}}{dt} = \sum_{j} \mathbf{M}_{o, \ j} + \left\{\sum_{in} \dot{m}_{i} \left(\mathbf{r}_{i} \times \mathbf{V}_{i}\right) -\sum_{out} \dot{m}_{e} \left(\mathbf{r}_{e} \times \mathbf{V}_{e} \right)\right\} \nonumber \] \[\text{where } \mathbf{M}_{o, j} = \mathbf{r}_{j} \times \mathbf{F}_{j} \quad \text{or} \quad M_{\text{couple, } j} \nonumber \] |
Contabilidad de Especies Químicas:\(\quad m_{j}=n_{j} M_{j}\) \[\text{mass} \quad \rightarrow \quad \frac{d m_{j, \ sys}}{d t} = \sum_{in} \dot{m}_{j, i} - \sum_{out} \dot{m}_{j, e} + \left(\dot{m}_{j, \ gen}-\dot{m}_{j, \ cons}\right) \nonumber \] \[ \text{molar} \quad \rightarrow \quad \frac{d n_{j, \ sys}}{dt} = \sum_{in} \dot{n}_{j, \ i} - \sum_{out} \dot{n}_{j, \ e} + \left( \dot{n}_{j, \ gen} - \dot{n}_{j, \ cons} \right) \nonumber \] |
Conservación de la Energía: \[\begin{gathered} E_{sys} = \int\limits_{V_{sys}} e \rho \ dV \quad \text { where } \quad e = u+\frac{V^{2}}{2}+gz+e_{\text {spring}} + \ldots \\ \frac{dE_{sys}}{dt} = \dot{Q}_{\text{net, in}} + \dot{W}_{\text {net, in}} + \left\{ \sum_{in} \dot{m}_{i} \left(h_{i} + \frac{V_{i}^{2}}{2} + gz_{i} \right) - \sum_{out} \dot{m}_{e} \left(h_{e} + \frac{V_{e}^{2}}{2} + gz_{e}\right) \right\} \end{gathered} \nonumber \] |
Conservación de Carga:\(\displaystyle \quad q_{sys} = \int\limits_{V_{sys}} \tilde{q} \rho \ dV\) \[\frac{d q_{sys}}{dt} = \sum_{in} \dot{q}_{i} - \sum_{out} \dot{q}_{e} \nonumber \] |
Contabilidad de Entropía:\(\displaystyle \quad S_{sys} = \int\limits_{V_{sys}} s \rho \ dV \quad \text{and} \quad S_{gen} \geq 0\) \[\frac{d S_{sys}}{dt} = \sum_{j} \frac{\dot{Q}_{j}}{T_{b, \ j}} + \left\{ \sum_{in} \dot{m}_{i} s_{i} - \sum_{out} \dot{m}_{e} s_{e}\right\} + \dot{S}_{gen} \nonumber \] |
C.2 Conversiones de Unidades
Conversiones de unidades | |
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Largo \[\begin{aligned} & 1 \mathrm{~ft} = 12 \mathrm{~in} = 0.3048 \mathrm{~m} = 1/3 \mathrm{~yd} \\ & 1 \mathrm{~m} = 100 \mathrm{~cm} = 1000 \mathrm{~mm} = 39.37 \mathrm{~in} = 3.2808 \mathrm{~ft} \\ & 1 \mathrm{~mile} = 5280 \mathrm{~ft} = 1609.3 \mathrm{~m} \end{aligned} \nonumber \] |
Fuerza \[\begin{aligned} & 1 \mathrm{~N} = 1 \mathrm{~kg} \cdot \mathrm{m}/\mathrm{s}^{2} = 0.22481 \mathrm{~lbf} \\ & 1 \mathrm{~lbf} = 1 \mathrm{~slug} \cdot \mathrm{ft}/\mathrm{s}^{2} = 32.174 \mathrm{~lbm} \cdot \mathrm{ft}/\mathrm{s}^{2} = 4.4482 \mathrm{~N} \end{aligned} \nonumber \] |
Masa \[\begin{aligned} &1 \mathrm{~kg} = 1000 \mathrm{~g} = 2.2046 \mathrm{~lbm} \\ &1 \mathrm{~lbm} = 16 \mathrm{~oz} = 0.45359 \mathrm{~kg} \\ &1 \mathrm{~slug} = 32.174 \mathrm{~lbm} \end{aligned} \nonumber \] |
Presión \[\begin{aligned} & 1 \mathrm{~atm} = 101.325 \mathrm{~kPa} = 1.01325 \mathrm{~bar} = 14.696 \mathrm{~lbf}/\mathrm{in}^{2} \\ & 1 \mathrm{~bar} = 100 \mathrm{~kPa} = 10^{5} \mathrm{~Pa} \\ & 1 \mathrm{~Pa} = 1 \mathrm{~N}/\mathrm{m}^{2} = 10^{-3} \mathrm{~kPa} \\ & 1 \mathrm{~lbf}/\mathrm{in}^{2} = 6.8947 \mathrm{~kPa} = 6894.7 \mathrm{~N}/\mathrm{m}^{2} \\ & \quad \left[ \mathrm{lbf}/\mathrm{in}^{2} \text{ often abbreviated as “psi”} \right] \end{aligned} \nonumber \] |
Valores de temperatura \[\begin{aligned} & (\mathrm{T} / \mathrm{K}) = \left(\mathrm{T} / { }^{\circ} \mathrm{R}\right) / 1.8 \\ & (\mathrm{T} / \mathrm{K}) = \left(\mathrm{T} / { }^{\circ} \mathrm{C} \right) + 273.15 \\ & \left(\mathrm{T} / { }^{\circ} \mathrm{C} \right) = \left[ \left( \mathrm{T} /{ }^{\circ} \mathrm{F} \right) - 32 \right]/1.8 \\ & \left(\mathrm{T} / \mathrm{R} \right) = 1.8 (\mathrm{T}/\mathrm{K}) \\ & \left( \mathrm{T}/{ }^{\circ} \mathrm{R}\right) = \left( \mathrm{T}/{ }^{\circ} \mathrm{F} \right) + 459.67 \\ & \left( \mathrm{T}/{ }^{\circ} \mathrm{F} \right) = 1.8 \left( \mathrm{T}/{ }^{\circ} \mathrm{C}\right) + 32 \end{aligned} \nonumber \] |
Energía \[\begin{aligned} & 1 \mathrm{~J} = 1 \mathrm{~N} \cdot \mathrm{m} \\ & 1 \mathrm{~kJ} = 1000 \mathrm{~J} = 737.56 \mathrm{~ft} \cdot \mathrm{lbf} = 0.94782 \mathrm{~Btu} \\ & 1 \mathrm{~Btu} = 1.0551 \mathrm{~kJ} = 778.17 \mathrm{~ft} \cdot \mathrm{lbf} \\ & 1 \mathrm{~ft} \cdot \mathrm{lbf} = 1.3558 \mathrm{~J} \end{aligned} \nonumber \] |
Diferencias de temperatura \[\begin{aligned} & (\Delta \mathrm{T}/{ }^{\circ} \mathrm{R}) = 1.8 (\Delta \mathrm{T}/\mathrm{K}) \\ & (\Delta \mathrm{T}/{ }^{\circ} \mathrm{R}) = (\Delta \mathrm{T}/{ }^{\circ} \mathrm{F}) \\ & (\Delta \mathrm{T}/\mathrm{K}) = (\Delta \mathrm{T}/{ }^{\circ} \mathrm{C}) \end{aligned} \nonumber \] |
Tasa de transferencia de energía \[\begin{aligned} & 1 \mathrm{~kW} = 1 \mathrm{~kJ}/\mathrm{s} = 737.56 \mathrm{~ft} \cdot \mathrm{lbf}/\mathrm{s} = 1.3410 \mathrm{~hp} = 0.94782 \mathrm{~Btu}/\mathrm{s} \\ & 1 \mathrm{~Btu}/\mathrm{s} = 1.0551 \mathrm{~kW} = 1.4149 \mathrm{~hp} = 778.17 \mathrm{~ft} \cdot \mathrm{lbf}/\mathrm{s} \\ & 1 \mathrm{~hp} = 550 \mathrm{~ft} \cdot \mathrm{lbf}/\mathrm{s} = 0.74571 \mathrm{~kW} = 0.70679 \mathrm{~Btu}/\mathrm{s} \end{aligned} \nonumber \] |
Volumen \[\begin{aligned} & 1 \mathrm{~m}^{3} = 1000 \mathrm{~L} = 10^{6} \mathrm{~cm}^{3} = 10^{6} \mathrm{~mL} = 35.315 \mathrm{~ft}^{3} = 264.17 \mathrm{~gal} \\ & 1 \mathrm{~ft}^{3} = 1728 \mathrm{~in}^{3} = 7.4805 \mathrm{~gal} = 0.028317 \mathrm{~m}^{3} \\ & 1 \mathrm{~gal} = 0.13368 \mathrm{~ft}^{3} = 0.0037854 \mathrm{~m}^{3} \end{aligned} \nonumber \] |
Energía Específica \[\begin{aligned} & 1 \mathrm{~kJ}/\mathrm{kg} = 1000 \mathrm{~m}^{2}/\mathrm{s}^{2} \\ & 1 \mathrm{~Btu}/\mathrm{lbm} = 25037 \mathrm{~ft}^{2}/\mathrm{s}^{2} \\ & 1 \mathrm{~ft} \cdot \mathrm{lbf}/\mathrm{lbm} = 32.174 \mathrm{~ft}^{2}/\mathrm{s}^{2} \end{aligned} \nonumber \] |
Caudal Volumétrico \[\begin{aligned} & 1 \mathrm{~m}^{3}/\mathrm{s} = 35.315 \mathrm{~ft}^{3}/\mathrm{s} = 264.17 \mathrm{~gal}/\mathrm{s} \\ & 1 \mathrm{~ft}^{3}/\mathrm{s} = 1.6990 \mathrm{~m}^{3}/\mathrm{min} = 7.4805 \mathrm{~gal}/\mathrm{s} = 448.83 \mathrm{~gal}/\mathrm{~min} \end{aligned} \nonumber \] |
C.3 Modelos de Sustancias
Dos Modelos de Sustancias (Relaciones Constitutivas) | ||
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Ecuación de Estado | ||
Modelo de Gas Ideal con calores específicos a temperatura ambiente |
Modelo de Sustancia Incompresible con calores específicos a temperatura ambiente |
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Se utiliza para modelar el comportamiento de | gases y vapores | líquidos y sólidos |
Supuestos básicos del modelo |
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\(P \ - \ T \ - \ \rho\)y\(P \ - \ T \ - \ \upsilon\) relaciones |
\(P=\rho RT\)y\(P \upsilon = RT\) donde\(R = R_{u}/M\) |
\(\upsilon = 1/\rho = \text{constant}\) Evaluado a temperatura ambiente |
Relaciones térmicas específicas | \(c_{\text{p}} - c_{\text{v}} = R; \quad k = c_{\text{p}} / c_{\text{v}}\) | \(c_{\text{p}} = c_{\text{v}} = c, \text{ a constant}\) |
\(c_{\text{p}}\)y\(c_{\text{v}}\) valores | Evaluado a temperatura ambiente | Evaluado a temperatura ambiente |
\(\Delta u\)— energía interna específica | \(\Delta u = u_{2}-u_{1} = c_{\text{v}} \left(T_{2}-T_{1}\right)\) | \(\Delta u = u_{2}-u_{1} = c \left(T_{2}-T_{1}\right)\) |
\(\Delta h\)— entalpía específica | \(\Delta h = h_{2}-h_{1} = c_{\text{p}} \left(T_{2} - T_{1}\right)\) | \[\begin{aligned} \Delta h &= h_{2}-h_{1} \\ &= \left(u_{2}+P_{2} \upsilon\right) - \left(u_{1}+P_{1} \upsilon\right) \\ &= \left(u_{2} - u_{1}\right) + \upsilon \left(P_{2}-P_{1}\right) \\ \text{thus}& \\ \Delta h &= \Delta u + \upsilon \Delta P = c \Delta T + \upsilon \Delta P \end{aligned} \nonumber \] |
\(\Delta s\)— entropía específica Nota: Todas las temperaturas son valores absolutos, es decir\({ }^{\circ} \mathrm{R}\),\(\mathrm{K}\) o, en las relaciones de entropía |
\[\begin{aligned} \Delta s &= s_{2}-s_{1} \\ &= c_{\text{p}} \ln \left(T_{2}-T_{1}\right) - R \ln \left(P_{2}-P_{1}\right) \\ &= c_{\text{v}} \ln \left(T_{2} / T_{1}\right) + R \ln \left(\upsilon_{2}-\upsilon_{1}\right) \end{aligned} \nonumber \] | \[\begin{aligned} \Delta s &= s_{2}-s_{1} \\ &= c \ln \left(T_{2}/T_{1}\right) \end{aligned} \nonumber \] |
Ecuación de Gas Ideal | |
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Bases Molares | Base Masiva |
\[\begin{array}{c} PV=nRT \\ P \bar{\upsilon} = R_{u} T \quad \text{and} \quad P = \bar{\rho} R_{u} T \end{array} \nonumber \] \[\begin{aligned} \text{where} & \\ P &= \text{absolute pressure of gas } \left[\text{kPa or lbf} / \mathrm{ft}^{2}\right] \\ V &= \text{volume of gas } \left[\mathrm{m}^{3} \text{ or } \mathrm{ft}^{3}\right] \\ n &= \text{number of moles of gas } \left[\text{kmol or lbmol}\right] \\ R_{u} &= \text{universal gas constant (the same for every gas)} \\ &\quad\quad \left[ \mathrm{kJ}/\left(\mathrm{kmol} \cdot \mathrm{K}\right) \text{ or } \left(\mathrm{ft} \cdot \mathrm{lbf}\right) / \left(\mathrm{lbmol} \cdot { }^{\circ} \mathrm{R}\right) \right] \\ T &= \text{absolute temperature of gas } \left[\mathrm{K} \text{ or } { }^{\circ} \mathrm{R}\right] \\ \bar{\rho} &= \text{molar density} = 1/\bar{\upsilon} \ \left[\mathrm{kmol}/\mathrm{m}^{3} \text{ or } \mathrm{lbmol}/\mathrm{ft}^{3} \right] \\ \bar{\upsilon} &= \text{molar specific volume } \left[\mathrm{m}^{3}/\mathrm{kmol} \text{ or } \mathrm{ft}^{3}/\mathrm{lbmol}\right] \end{aligned} \nonumber \] |
\[\begin{array}{c} PV=mRT \\ P \upsilon = RT \quad \text{and} \quad P = \rho R T \end{array} \nonumber \] \[\begin{aligned} \text{where} & \\ P &= \text{absolute pressure of gas } \left[\text{kPa or lbf} / \mathrm{ft}^{2}\right] \\ V &= \text{volume of gas } \left[\mathrm{m}^{3} \text{ or } \mathrm{ft}^{3}\right] \\ m &= \text{mass of gas } \left[\mathrm{kg} \text{ or } \mathrm{lbm}\right] \\ R &= \text{specific gas constant (different for each gas)} \\ &\quad\quad \left[\mathrm{kJ} / \left(\mathrm{kg} \cdot \mathrm{K}\right) \text{ or } \left(\mathrm{ft} \cdot \mathrm{lbf}\right) / \left(\mathrm{lbmol} \cdot { }^{\circ} \mathrm{R}\right) \right] \\ T &= \text{absolute temperature of gas } \left[\mathrm{K} \text{ or } { }^{\circ} \mathrm{R}\right] \\ \rho &= \text{density} = 1/\upsilon \ \left[ \mathrm{kg}/\mathrm{m}^{3} \text{ or } \mathrm{lbm}/\mathrm{ft}^{3} \right] \\ \upsilon &= \text{specific volume } \left[ \mathrm{m}^{3}/\mathrm{kg} \text{ or } \mathrm{ft}^{3}/\mathrm{lbm} \right] \end{aligned} \nonumber \] |
\(\text{and}\) \[\begin{aligned} R_{u} &= 8.314 \ \frac{\mathrm{kJ}}{\mathrm{kmol} \cdot \mathrm{K}} = 8.314 \ \frac{\mathrm{J}}{\mathrm{mol} \cdot \mathrm{K}} \\ &= 1545 \ \frac{\mathrm{ft} \cdot \mathrm{lbf}}{\mathrm{lbmol} \cdot { }^{\circ} \mathrm{R}} \end{aligned} \nonumber \] |
\(\text{and}\)\[ R = \frac{R_{u}}{M} \nonumber \] \(\text{where}\)\[\quad M = \text{molecular weight (molar mass) of a specific gas} \nonumber \] |
Datos de Propiedades Termofísicas para Algunas Sustancias Comunes (Unidades SI) | ||||||||
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Gases (at\(25^{\circ} \mathrm{C}\) y\(1 \mathrm{~atm}\)) | ||||||||
Sustancia | Masa molar | \(\dfrac{R}{\left[ \dfrac{\mathrm{kJ}}{\mathrm{kg} \cdot \mathrm{K}} \right]}\) | \(\dfrac{c_{v}}{\left[ \dfrac{\mathrm{kJ}}{\mathrm{kg} \cdot \mathrm{K}} \right]}\) | \(\dfrac{c_{p}}{\left[ \dfrac{\mathrm{kJ}}{\mathrm{kg} \cdot \mathrm{K}} \right]}\) | \(k\) | \(\dfrac{T_{c}}{\mathrm{K}}\) | \(\dfrac{P_{c}}{\mathrm{bar}}\) | |
Acetileno | \(\mathrm{C}_{2} \mathrm{H}_{2}\) | \(26.04\) | \(0.3193\) | \(1.37\) | \(1.69\) | \(1.23\) | \(309\) | \(62.4\) |
Aire | — | \(28.97\) | \(0.2870\) | \(0.718\) | \(1.005\) | \(1.40\) | \(133\) | \(37.7\) |
Amoníaco | \(\mathrm{NH}_{3}\) | \(17.04\) | \(0.4879\) | \(1.66\) | \(2.15\) | \(1.30\) | \(406\) | \(112.8\) |
Dióxido de carbono | \(\mathrm{CO}_{2}\) | \(44.01\) | \(0.1889\) | \(0.657\) | \(0.846\) | \(1.29\) | \(304.2\) | \(73.9\) |
Monóxido de carbono | \(\mathrm{CO}\) | \(28.01\) | \(0.2968\) | \(0.744\) | \(1.04\) | \(1.40\) | \(133\) | \(35.0\) |
Etanos | \(\mathrm{C}_{2} \mathrm{H}_{6}\) | \(30.07\) | \(0.2765\) | \(1.48\) | \(1.75\) | \(1.18\) | \(305.4\) | \(48.8\) |
Etileno | \(\mathrm{C}_{2} \mathrm{H}_{4}\) | \(28.05\) | \(0.2964\) | \(1.23\) | \(1.53\) | \(1.24\) | \(283\) | \(51.2\) |
Helio | \(\mathrm{He}\) | \(4.003\) | \(2.077\) | \(3.12\) | \(5.19\) | \(1.67\) | \(5.2\) | \(2.3\) |
Hidrógeno | \(\mathrm{H}_{2}\) | \(2.016\) | \(4.124\) | \(10.2\) | \(14.3\) | \(1.40\) | \(33.2\) | \(13.0\) |
Metano | \(\mathrm{CH}_{4}\) | \(16.04\) | \(0.5183\) | \(1.70\) | \(2.22\) | \(1.31\) | \(190.7\) | \(46.4\) |
Nitrógeno | \(\mathrm{N}_{2}\) | \(28.01\) | \(0.2968\) | \(0.743\) | \(1.04\) | \(1.40\) | \(126.2\) | \(33.9\) |
Oxígeno | \(\mathrm{O}_{2}\) | \(32.00\) | \(0.2598\) | \(0.658\) | \(0.918\) | \(1.40\) | \ (154.4\ | \(50.5\) |
Propano | \(\mathrm{C}_{3} \mathrm{H}_{8}\) | \(44.09\) | \(0.1886\) | \(1.48\) | \(1.67\) | \(1.13\) | \(370\) | \(42.5\) |
Refrigerante 134a | \(\mathrm{C}_{2} \mathrm{F}_{2} \mathrm{H}_{2}\) | \(102.03\) | \(0.08149\) | \(0.76\) | \(0.85\) | \(1.12\) | \(374.3\) | \(40.6\) |
Agua (Vapor) | \(\mathrm{H}_{2} \mathrm{O}\) | \(18.02\) | \(0.4614\) | \(1.40\) | \(1.86\) | \(1.33\) | \(647.3\) | \(220.9\) |
Líquidos | Sólidos* | |||||
Sustancia | Temp. \(({ }^{\circ} \mathrm{C})\) | \(\dfrac{\rho}{\left[ \dfrac{\mathrm{kg}}{\mathrm{m}^{3}}\right]}\) | \(\dfrac{c_{p}}{\left[ \dfrac{\mathrm{kJ}}{\mathrm{kg} \cdot \mathrm{K}} \right]}\) | Sustancia | \(\dfrac{\rho}{\left[ \dfrac{\mathrm{kg}}{\mathrm{m}^{3}}\right]}\) | \(\dfrac{c_{p}}{\left[ \dfrac{\mathrm{kJ}}{\mathrm{kg} \cdot \mathrm{K}} \right]}\) |
Amoníaco | \(25\) | \(602\) | \(4.80\) | Aluminio | \(2,700\) | \(0.902\) |
Benceno | \(20\) | \(879\) | \(1.72\) | Latón, amarillo | \(8,310\) | \(0.400\) |
Salmuera\((20 \% \mathrm{NaCl})\) | \(20\) | \(1,150\) | \(3.11\) | Ladrillo (común) | \(1,922\) | \(0.79\) |
Etanol | \(25\) | \(783\) | \(2.46\) | Concreto | \(2,300\) | \(0.653\) |
Alcohol etílico | \(20\) | \(789\) | \(2.84\) | Cobre | \(8,900\) | \(0.386\) |
Etilenglicol | \(20\) | \(1,109\) | \(2.84\) | Vidrio, ventana | \(2,700\) | \(0.800\) |
Queroseno | \(20\) | \(820\) | \(2.00\) | Hierro | \(7,840\) | \(0.45\) |
Mercurio | \(25\) | \(13,560\) | \(0.139\) | Plomo | \(11,310\) | \(0.128\) |
Aceite (ligero) | \(25\) | \(910\) | \(1.80\) | Plata | \(10,470\) | \(0.235\) |
Refrigerante 134a | \(25\) | \(1,206\) | \(1.42\) | Acero (suave) | \(7,830\) | \(0.500\) |
Agua | \(25\) | \(997\) | \(4.18\) | * Evaluado a temperatura ambiente. | ||
Valores adaptados de K. Wart, Jr. y D. E. Richards, Termodinámica, 6a ed. (McGraw-Hill, Nueva York, 1999) e Y. A. Cengul y M. A. Boles, Termodinámica, 4ta ed. (McGraw-Hill, Nueva York, 2002). |
Datos de Propiedades Termofísicas para Algunas Sustancias Comunes (Unidades USCS) | ||||||||
---|---|---|---|---|---|---|---|---|
Gases (at\(77^{\circ} \mathrm{F}\) y\(1 \mathrm{~atm}\)) | ||||||||
Sustancia | Masa molar | \(\dfrac{R}{\left[ \dfrac{\mathrm{ft} \cdot \mathrm{lbf}}{\mathrm{lbm} \cdot { }^{\circ} \mathrm{R}} \right]}\) | \(\dfrac{c_{v}}{\left[ \dfrac{\mathrm{Btu}}{\mathrm{lbm} \cdot { }^{\circ} \mathrm{R}} \right]}\) | \(\dfrac{c_{p}}{\left[ \dfrac{\mathrm{Btu}}{\mathrm{lbm} \cdot { }^{\circ} \mathrm{R}} \right]}\) | \(k\) | \(\dfrac{T_{c}}{\text{ }^{\circ} \mathrm{R}}\) | \(\dfrac{P_{c}}{\mathrm{atm}}\) | |
Acetileno | \(\mathrm{C}_{2} \mathrm{H}_{2}\) | \(26.04\) | \(59.33\) | \(0.328\) | \(0.404\) | \(1.23\) | \(556\) | \(61.6\) |
Aire | — | \(28.97\) | \(53.33\) | \(0.171\) | \(0.240\) | \(1.40\) | \(239\) | \(37.2\) |
Amoníaco | \(\mathrm{NH}_{3}\) | \(17.04\) | \(90.67\) | \(0.397\) | \(0.514\) | \(1.29\) | \(730\) | \(111.3\) |
Dióxido de carbono | \(\mathrm{CO}_{2}\) | \(44.01\) | \(35.11\) | \(0.156\) | \(0.202\) | \(1.29\) | \(548\) | \(72.9\) |
Monóxido de carbono | \(\mathrm{CO}\) | \(28.01\) | \(55.16\) | \(0.178\) | \(0.249\) | \(1.40\) | \(239\) | \(34.5\) |
Etanos | \(\mathrm{C}_{2} \mathrm{H}_{6}\) | \(30.07\) | \(51.38\) | \(0.353\) | \(0.419\) | \(1.19\) | \(549\) | \(48.2\) |
Etileno | \(\mathrm{C}_{2} \mathrm{H}_{4}\) | \(28.05\) | \(55.08\) | \(0.294\) | \(0.365\) | \(1.24\) | \(510\) | \(50.5\) |
Helio | \(\mathrm{He}\) | \(4.003\) | \(386.0\) | \(0.744\) | \(1.24\) | \(1.67\) | \(9.3\) | \(2.26\) |
Hidrógeno | \(\mathrm{H}_{2}\) | \(2.016\) | \(766.4\) | \(2.43\) | \(3.42\) | \(1.40\) | \(59.8\) | \(12.8\) |
Metano | \(\mathrm{CH}_{4}\) | \(16.04\) | \(96.32\) | \(0.407\) | \(0.531\) | \(1.30\) | \(344\) | \(45.8\) |
Nitrógeno | \(\mathrm{N}_{2}\) | \(28.01\) | \(55.16\) | \(0.178\) | \(0.248\) | \(1.39\) | \(227\) | \(33.5\) |
Oxígeno | \(\mathrm{O}_{2}\) | \(32.00\) | \(48.28\) | \(0.157\) | \(0.219\) | \(1.40\) | \(278\) | \(49.8\) |
Propano | \(\mathrm{C}_{3} \mathrm{H}_{8}\) | \(44.09\) | \(35.04\) | \(0.355\) | \(0.400\) | \(1.13\) | \(666\) | \(42.1\) |
Refrigerante 134a | \(\mathrm{C}_{2} \mathrm{F}_{4} \mathrm{H}_{2}\) | \(102.03\) | \(15.14\) | \(0.184\) | \(0.203\) | \(1.10\) | \(672.8\) | \(40.1\) |
Agua (Vapor) | \(\mathrm{H}_{2} \mathrm{O}\) | \(18.02\) | \(87.74\) | \(0.335\) | \(0.445\) | \(1.33\) | \(1165\) | \(218.0\) |
Líquidos | Sólidos* | |||||
Sustancia | Temp\(({ }^{\circ} \mathrm{F})\) | \(\dfrac{\rho}{\left[ \dfrac{\mathrm{lbm}}{\mathrm{ft}^{3}} \right]}\) | \(\dfrac{c_{p}}{\left[ \dfrac{\mathrm{Btu}}{\mathrm{lbm} \cdot { }^{\circ} \mathrm{R}} \right]}\) | Sustancia | \(\dfrac{\rho}{\left[ \dfrac{\mathrm{lbm}}{\mathrm{ft}^{3}} \right]}\) | \(\dfrac{c_{p}}{\left[ \dfrac{\mathrm{Btu}}{\mathrm{lbm} \cdot { }^{\circ} \mathrm{R}} \right]}\) |
Amoníaco | \(80\) | \(37.5\) | \(1.135\) | Aluminio | \(170\) | \(0.215\) |
Benceno | \(68\) | \(54.9\) | \(0.411\) | Latón, amarillo | \(519\) | \(0.0955\) |
Salmuera\((20 \% \mathrm{NaCl})\) | \(68\) | \(71.8\) | \(0.743\) | Ladrillo (común) | \(120\) | \(0.189\) |
Etanol | \(77\) | \(48.9\) | \(0.588\) | Concreto | \(144\) | \(0.156\) |
Alcohol etílico | \(68\) | \(49.3\) | \(0.678\) | Cobre | \(555\) | \(0.0917\) |
Etilenglicol | \(68\) | \(69.2\) | \(0.678\) | Vidrio, ventana | \(169\) | \(0.191\) |
Queroseno | \(68\) | \(51.2\) | \(0.478\) | Hierro | \(490\) | \(0.107\) |
Mercurio | \(77\) | \(847\) | \(0.033\) | Plomo | \(705\) | \(0.030\) |
Aceite (ligero) | \(77\) | \(56.8\) | \(0.430\) | Plata | \(655\) | \(0.056\) |
Refrigerante 134a | \(32\) | \(80.9\) | \(0.318\) | Acero (suave) | \(489\) | \(0.119\) |
Agua | \(68\) | \(62.2\) | \(1.00\) | * Evaluado a temperatura ambiente. | ||
Valores adaptados de K. Wart, Jr. y D. E. Richards, Termodinámica, 6a ed. (McGraw-Hill, Nueva York, 1999) e Y. A. Cengul y M. A. Boles, Termodinámica, 4ta ed. (McGraw-Hill, Nueva York, 2002). |