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MEASUR-Tools-Suite v1.0.11
The MEASUR Tools Suite is a collection of industrial efficiency calculations written in C++ and with bindings for compilation to WebAssembly.
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First estimate modification power from pressure terms, then multiply by annual operating hours. The ratio \(x\) converts the proposed pressure from gauge (psig) to absolute (psia) using the user-supplied atmospheric pressure \(P_{atm}\). The ratio \(r\) converts the rated compressor pressure from psig to psia using an assumed standard atmospheric pressure of \(14.7\) \([\unit{\psi}]\). The exponent \(c = (k-1)/k\) is the isentropic exponent derived from the heat capacity ratio \(k = 1.395\) for air (ratio of specific heats \(c_p/c_v\)).
\begin{equation}\label{eq:compressed-air-pressure-reduction-modification-power} P_{mod} = P_{comp} \cdot \frac{x^c - 1}{r^c - 1}\end{equation}
\begin{equation}\label{eq:compressed-air-pressure-reduction-modification-ratio-x} x = \frac{P_{proposed} + P_{atm}}{P_{atm}}\end{equation}
\begin{equation}\label{eq:compressed-air-pressure-reduction-modification-ratio-r} r = \frac{P_{rated} + 14.7}{14.7}\end{equation}
\begin{equation}\label{eq:compressed-air-pressure-reduction-modification-c} c = \frac{k-1}{k}\end{equation}
\begin{equation}\label{eq:compressed-air-pressure-reduction-modification-energy} E_{use} = P_{mod} \cdot t_{op}\end{equation}
| \(E_{use}\) | Annual energy use \([\unit{ \kWh\per\year}]\) |
| \(P_{mod}\) | Modification compressor power estimate \([\unit{ \kW}]\) |
| \(P_{comp}\) | Compressor power \([\unit{ \kW}]\) |
| \(P_{proposed}\) | Proposed compressor discharge pressure (psig) \([\unit{ \psi}]\) |
| \(P_{atm}\) | Atmospheric pressure (user-supplied, converts psig to psia) \([\unit{ \psi}]\) |
| \(P_{rated}\) | Rated compressor discharge pressure (psig) \([\unit{ \psi}]\) |
| \(14.7\) | Assumed standard atmospheric pressure (converts \(P_{rated}\) from psig to psia) \([\unit{ \psi}]\) |
| \(x\) | Proposed absolute pressure ratio \([\unit{ \unitless}]\) |
| \(r\) | Rated absolute pressure ratio \([\unit{ \unitless}]\) |
| \(c\) | Isentropic exponent, (k-1)/k \([\unit{ \unitless}]\) |
| \(k\) | Heat capacity ratio of air, c_p/c_v (1.395) \([\unit{ \unitless}]\) |
| \(t_{op}\) | Annual operating hours \([\unit{ \hour\per\year}]\) |
1.9.8