:: Design and More Formulars @ Tricks:: Air values calculator::

Air values calculator

Select unit system: English Metric

INPUTS

Altitude

Speed

Reference Length

RESULTS

Temperature

Density

Pressure

Speed of Sound

Viscosity

Mach Number

Dynamic Pressure

Critical Cp

Vacuum Cp

Reynolds Number

Laminar Cf

Turbulent Cf

เอาไปใช้กับเวปของท่าน

<table border="1" cellpadding="0" bgcolor="#F2FCFF" bordercolor="#9FBAD0">
<tr>
<td>
<SCRIPT LANGUAGE="JavaScript">
// By Ilan Kroo kroo@leland.stanford.edu (http://aero.stanford.edu/People/kroo.html)
// Courtesy of SimplytheBest.net (http://simplythebest.net/info/dhtml_scripts.html)
function setEUnits()
{
var str=document.forms[1].hunits.value;
if(str=="ft")
{
alert("Already in English Units.");
return;
}
document.forms[1].hunits.value="ft"
document.forms[1].vunits.value="ft/sec"
document.forms[1].lunits.value="ft"
document.forms[2].tunits.value="deg R"
document.forms[2].runits.value="sl/ft^3"
document.forms[2].punits.value="lb/ft^2"
document.forms[2].sunits.value="ft/sec"
document.forms[2].muunits.value="lb sec/ft^2"
document.forms[2].qunits.value="lb/ft^2"
var h=document.forms[1].alt.value;
var v=document.forms[1].speed.value;
var rl=document.forms[1].rlength.value;
var tempVal=document.forms[2].temp.value
var rhoVal=document.forms[2].rho.value
var pVal=document.forms[2].press.value
var soundVal=document.forms[2].ssound.value
var viscVal=document.forms[2].visc.value
var machVal=document.forms[2].mach.value
var qVal=document.forms[2].q.value
var cpstarVal=document.forms[2].cpstar.value
var cpminVal=document.forms[2].cpmin.value
var reynolds=document.forms[2].reno.value
var cflam=document.forms[2].cfl.value
var cfturb=document.forms[2].cft.value
document.forms[1].alt.value=h*3.2808
document.forms[1].speed.value=v*3.2808
document.forms[1].rlength.value=rl*3.2808
document.forms[2].temp.value=tempVal*1.8
document.forms[2].rho.value=rhoVal*.068521*.028317
document.forms[2].press.value=pVal*.020885
document.forms[2].ssound.value=soundVal*3.2808
document.forms[2].visc.value=viscVal*.22481*.092903
document.forms[2].mach.value=machVal
document.forms[2].q.value=qVal*.020885
document.forms[2].cpstar.value=cpstarVal
document.forms[2].cpmin.value=cpminVal
document.forms[2].reno.value=reynolds
document.forms[2].cfl.value=cflam
document.forms[2].cft.value=cfturb
roundAll();
}
function setMUnits()
{
var str=document.forms[1].hunits.value;
if(str=="m")
{
alert("Already in metric units.");
return;
}
Compute();
document.forms[1].hunits.value="m"
document.forms[1].vunits.value="m/sec"
document.forms[1].lunits.value="m"
document.forms[2].tunits.value="deg K"
document.forms[2].runits.value="kg/m^3"
document.forms[2].punits.value="N/m^2"
document.forms[2].sunits.value="m/sec"
document.forms[2].muunits.value="N sec/m^2"
document.forms[2].qunits.value="N/m^2"
var h=document.forms[1].alt.value;
var v=document.forms[1].speed.value;
var rl=document.forms[1].rlength.value;
var tempVal=document.forms[2].temp.value
var rhoVal=document.forms[2].rho.value
var pVal=document.forms[2].press.value
var soundVal=document.forms[2].ssound.value
var viscVal=document.forms[2].visc.value
var machVal=document.forms[2].mach.value
var qVal=document.forms[2].q.value
var cpstarVal=document.forms[2].cpstar.value
var cpminVal=document.forms[2].cpmin.value
var reynolds=document.forms[2].reno.value
var cflam=document.forms[2].cfl.value
var cfturb=document.forms[2].cft.value
document.forms[1].alt.value=h/3.2808
document.forms[1].speed.value=v/3.2808
document.forms[1].rlength.value=rl/3.2808
document.forms[2].temp.value=tempVal/1.8
document.forms[2].rho.value=rhoVal/.068521/.028317
document.forms[2].press.value=pVal/.020885
document.forms[2].ssound.value=soundVal/3.2808
document.forms[2].visc.value=viscVal/.22481/.092903
document.forms[2].mach.value=machVal
document.forms[2].q.value=qVal/.020885
document.forms[2].cpstar.value=cpstarVal
document.forms[2].cpmin.value=cpminVal
document.forms[2].reno.value=reynolds
document.forms[2].cfl.value=cflam
document.forms[2].cft.value=cfturb
roundAll();
}
function ResetForm()
{
document.forms[1].alt.value="0.0"
document.forms[1].speed.value="1.0"
document.forms[1].rlength.value="1.0"
}
function Compute()
{
// First set to English Units
var origUnits="english";
var str=document.forms[1].hunits.value;
if(str=="m")
{
origUnits="metric";
setEUnits();
}
var h=document.forms[1].alt.value;
var v=document.forms[1].speed.value;
var rl=document.forms[1].rlength.value;
var TEMPSL=518.67;
var RHOSL=0.00237689;
var PRESSSL=2116.22;
var saTheta=1.0
var saSigma=1.0
var saDelta=1.0
if(h<232940)
{
saTheta=1.434843-h/337634;
saSigma=Math.pow(0.79899-h/606330,11.20114);
saDelta=Math.pow(0.838263-h/577922,12.20114);
}
if(h<167323)
{
saTheta=0.939268;
saSigma=0.00116533*Math.exp((h-154200)/-25992);
saDelta=0.00109456*Math.exp((h-154200)/-25992);
}
if(h<154199)
{
saTheta=0.482561+h/337634;
saSigma=Math.pow(0.857003+h/190115,-13.20114);
saDelta=Math.pow(0.898309+h/181373,-12.20114);
}
if(h<104987)
{
saTheta=0.682457+h/945374;
saSigma=Math.pow(0.978261+h/659515,-35.16319);
saDelta=Math.pow(0.988626+h/652600,-34.16319);
}
if(h<65617)
{
saTheta=0.751865;
saSigma=0.297076*Math.exp((36089-h)/20806);
saDelta=0.223361*Math.exp((36089-h)/20806);
}
if(h<36089)
{
saTheta=1.0-h/145442;
saSigma=Math.pow(1.0-h/145442,4.255876);
saDelta=Math.pow(1.0-h/145442,5.255876);
}
var tempVal=TEMPSL*saTheta;
var rhoVal=RHOSL*saSigma;
var pVal=PRESSSL*saDelta;
var viscVal=0.0226968*Math.pow(tempVal,1.5)/((tempVal)+198.72)/1000000.0;
var soundVal=Math.sqrt(1.4*1716.56*(tempVal));
var machVal=v/soundVal
var qVal=0.7*pVal*machVal*machVal
var reynolds=v*rl*rhoVal/viscVal
var cfturb=0.455/Math.pow((Math.log(reynolds)/Math.log(10)),2.58)
var cflam=1.328/Math.sqrt(reynolds)
document.forms[2].temp.value=tempVal
document.forms[2].rho.value=rhoVal
document.forms[2].press.value=pVal
document.forms[2].ssound.value=soundVal
document.forms[2].visc.value=viscVal
document.forms[2].mach.value=machVal
document.forms[2].q.value=qVal
document.forms[2].cpstar.value=(Math.pow((1/1.2+machVal*machVal/6.0),3.5)-1)/(0.7*machVal*machVal)
document.forms[2].cpmin.value=-1.0/(0.7*machVal*machVal)
document.forms[2].reno.value=reynolds
document.forms[2].cfl.value=cflam
document.forms[2].cft.value=cfturb
if(origUnits=="metric")
{
setMUnits();
}
roundAll();
}
// Rounding
function roundAll()
{
document.forms[1].alt.value=truncNum(document.forms[1].alt.value,9)
document.forms[1].speed.value=truncNum(document.forms[1].speed.value,7)
document.forms[1].rlength.value=truncNum(document.forms[1].rlength.value,7)
document.forms[2].temp.value=truncNum(document.forms[2].temp.value,7)
document.forms[2].rho.value=truncNum(document.forms[2].rho.value,7)
document.forms[2].press.value=truncNum(document.forms[2].press.value,7)
document.forms[2].ssound.value=truncNum(document.forms[2].ssound.value,8)
document.forms[2].visc.value=truncNum(document.forms[2].visc.value,10)
document.forms[2].mach.value=truncNum(document.forms[2].mach.value,6)
document.forms[2].q.value=truncNum(document.forms[2].q.value,7)
document.forms[2].cpstar.value=truncNum(document.forms[2].cpstar.value,6)
document.forms[2].cpmin.value=truncNum(document.forms[2].cpmin.value,6)
document.forms[2].reno.value=truncNum(document.forms[2].reno.value,9)
document.forms[2].cfl.value=truncNum(document.forms[2].cfl.value,7)
document.forms[2].cft.value=truncNum(document.forms[2].cft.value,7)
return;
}
function truncNum(inputVal,rsize)
{
var instr=" "+inputVal
var inputlength=instr.length
if(inputlength<=rsize+1)return instr.substring(1,inputlength);
var epos=strpos(instr,"e")
if(epos>rsize+1)
{
var instr1=instr.substring(1,rsize+1)+instr.substring(epos,inputlength);
return instr1;
}
var rounded=instr.substring(1,rsize+1);
return rounded;
}
function strpos(str,ch)
{
for(var i=0;
i<str.length;
i++)
if(str.substring(i,i+1)==ch)return i;
return-1;
}</SCRIPT>
<p align="center"><br>
<font face="Arial" color="#CC3333"><b>Air values calculator</b></font></p>
<form name="units">
<p align="left"><b><font face="Arial" size="2"> Select unit system: <input type="radio" value="radio1" name="unitbut" checked onclick="setEUnits()">
<i>English</i> <input type="radio" value="radio2" name="unitbut" onclick="setMUnits()">
<i>Metric</i></font></b></p>
</form>
<h3 align="left"><font face="Arial" color="#FF0000" size="2"> INPUTS</font></h3>
<form name="inputs">
<table>
<tr>
<td>
<p align="left"><b><font face="Arial" size="2">Altitude</font></b></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="alt" type="text" value="0.0" size="15"></font></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="hunits" type="text" size="6" value="ft"></font></p>
</td>
</tr>
<tr>
<td>
<p align="left"><b><font face="Arial" size="2">Speed</font></b></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="speed" type="text" value="1.0" size="15"></font></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="vunits" type="text" size="6" value="ft/sec"></font></p>
</td>
</tr>
<tr>
<td>
<p align="left"><b><font face="Arial" size="2">Reference Length</font></b></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="rlength" type="text" value="1.0" size="15"></font></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="lunits" type="text" size="6" value="ft"></font></p>
</td>
</tr>
</table>
<p align="left"><font face="Arial" size="2">  <input name="name1" type="button" value="Compute" onclick="Compute()">
<input name="name" type="button" value="Reset" onclick="ResetForm()"></font></p>
</form>
<h3 align="left"><font face="Arial" color="#FF0000" size="2"> RESULTS</font></h3>
<form name="results">
<table>
<tr>
<td>
<p align="left"><b><font face="Arial" size="2">Temperature</font></b></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="temp" type="text" size="15"></font></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="tunits" type="text" size="8" value="?R"></font></p>
</td>
</tr>
<tr>
<td>
<p align="left"><b><font face="Arial" size="2">Density</font></b></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="rho" type="text" size="15"></font></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="runits" type="text" size="8" value="sl/ft^3"></font></p>
</td>
</tr>
<tr>
<td>
<p align="left"><b><font face="Arial" size="2">Pressure</font></b></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="press" type="text" size="15"></font></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="punits" type="text" size="8" value="lb/ft^2"></font></p>
</td>
</tr>
<tr>
<td>
<p align="left"><b><font face="Arial" size="2">Speed of Sound</font></b></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="ssound" type="text" size="15"></font></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="sunits" type="text" size="8" value="ft/sec"></font></p>
</td>
</tr>
<tr>
<td>
<p align="left"><b><font face="Arial" size="2">Viscosity</font></b></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="visc" type="text" size="15"></font></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="muunits" type="text" size="8" value="lb sec/ft^2"></font></p>
</td>
<tr>
<td>
<p align="left"><b><font face="Arial" size="2">Mach Number</font></b></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="mach" type="text" size="15"></font></p>
</td>
</tr>
<tr>
<td>
<p align="left"><b><font face="Arial" size="2">Dynamic Pressure</font></b></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="q" type="text" size="15"></font></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="qunits" type="text" size="8" value="lb/ft^2"></font></p>
</td>
</tr>
<tr>
<td>
<p align="left"><b><font face="Arial" size="2">Critical Cp</font></b></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="cpstar" type="text" size="15"></font></p>
</td>
</tr>
<tr>
<td>
<p align="left"><b><font face="Arial" size="2">Vacuum Cp</font></b></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="cpmin" type="text" size="15"></font></p>
</td>
<tr>
<td>
<p align="left"><b><font face="Arial" size="2">Reynolds Number</font></b></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="reno" type="text" size="15"></font></p>
</td>
</tr>
<tr>
<td>
<p align="left"><b><font face="Arial" size="2">Laminar Cf</font></b></p>
</td>
<td>
<p align="left"><font face="Arial" size="2"><input name="cfl" type="text" size="15"></font></p>
</td>
</tr>
<tr>
<td>
<p align="left"><b><font face="Arial" size="2">Turbulent Cf</font></b></p>
</td>
<td>
<p align="left"><input name="cft" type="text" size="15"></p>
</td>
</tr>
</table>
</form>
</td>
</tr>
</table>