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Open Channel Calculator

Open Channel Calculator

{source}
<table width=”100%” border=”0″ cellspacing=”0″ cellpadding=”5″>
                    <tr>
                     <td valign=”top”> <SCRIPT src=”opencalc.js”>

</SCRIPT> <FORM method=post>
                         <TABLE border=1 cellSpacing=5 class=”size12pt”>
                            <TBODY>
                             <TR>
                                <TH>Required Information</TH>
                             <TR>
                                <TD>Enter the Slope:</TD>
                                <TD><INPUT onchange=SetSlope(this) size=4 name=FSlope></TD>
                                <TD>Enter the <B>Channel</B> Top Width (feet):</TD>
                                <TD><INPUT onchange=SetTw(this) size=4 name=FTw></TD>
                             </TR>
                             <TR>
                                <TD>Enter the <B>Channel</B> Bottom Width (feet):</TD>
                                <TD><INPUT onchange=SetBw(this) size=4 name=FBw></TD>
                                <TD>Enter the <B>Channel</B> Height (feet):</TD>
                                <TD><INPUT onchange=SetHeight(this) size=4 name=FHeight></TD>
                             </TR>
                             <TR>
                                <TD>Enter the <B>Flow</B> Depth (feet):</TD>
                                <TD><INPUT onchange=SetDepth(this) size=4 name=FDepth></TD>
                                <TD>Enter the n value:</TD>
                                <TD><INPUT onchange=Setnval(this) size=4 name=Fnval></TD>
                             </TR>
                            </TBODY>
                         </TABLE>
                         <P>
                         <TABLE cellSpacing=5 border=1>
                            <TBODY>
                             <TR>
                                <TD colSpan=2><INPUT name=”button” type=button onclick=Opencalc(this.form) value=Calculate!></TD>
                                <TD
    colSpan=2><INPUT type=reset value=Reset name=Reset></TD>
                             </TR>
                            </TBODY>
                         </TABLE>
                         <table width=”100%” border=”0″ cellspacing=”0″ cellpadding=”5″>
                            <tr>
                             <td valign=”top”><TABLE border=1 cellSpacing=5 class=”size12pt”>
                                 <TBODY>
                                    <TR>
                                     <TH colSpan=3>Results</TH>
                                    <TR>
                                     <TD colSpan=3>The wetted perimeter is
                                        <INPUT size=3 name=FPer>
                                        Feet.
                                        <P></P></TD>
                                    </TR>
                                    <TR>
                                     <TD colSpan=3>The <B>flow</B> area is
                                        <INPUT
     size=3 name=Farea>
                                        Square Feet.
                                        <P></P></TD>
                                    </TR>
                                    <TR>
                                     <TD colSpan=3>The hydraulic radius is
                                        <INPUT size=3 name=FRh>
                                        Feet.
                                        <P></P></TD>
                                    </TR>
                                    <TR>
                                     <TD colSpan=3>The C value is
                                        <INPUT size=4 name=FCval> <P></P></TD>
                                    </TR>
                                    <TR>
                                     <TD colSpan=3>The <B>flow</B> is
                                        <INPUT size=4
     name=Fcfs>
                                        CFS.
                                        <P></P></TD>
                                    </TR>
                                    <TR>
                                     <TD colSpan=3>The <B>flow</B> is
                                        <INPUT size=6
     name=Fgpm>
                                        GPM.
                                        <P></P></TD>
                                    </TR>
                                    <TR>
                                     <TD colSpan=3>The velocity is
                                        <INPUT size=4 name=Fvel>
                                        FPS.
                                        <P></P></TD>
                                    </TR>
                                 </TBODY>
                                </TABLE></td>
                             <td width=”50%” valign=”top”><span class=”size12pt”><strong>Design
                                Use Values of Manning’s <i>n</i> </strong></span>
                                <TABLE BORDER CELLSPACING=5 class=”size10pt”>
                                 <TR>
                                    <TD><b>Channel Material</b></TD>
                                    <TD><i><b>n</b></i></TD>
                                 </TR>
                                 <TR>
                                    <TD>clean, uncoated cast iron</TD>
                                    <TD>0.013-0.015</TD>
                                 </TR>
                                 <TR>
                                    <TD>clean, coated cast iron</TD>
                                    <TD>0.012-0.014</TD>
                                 </TR>
                                 <TR>
                                    <TD>dirty, tuberculed cast iron</TD>
                                    <TD>0.015-0.035</TD>
                                 </TR>
                                 <TR>
                                    <TD>riveted steel</TD>
                                    <TD>0.015-0.017</TD>
                                 </TR>
                                 <TR>
                                    <TD>lock-bar and welded</TD>
                                    <TD>0.012-0.013</TD>
                                 </TR>
                                 <TR>
                                    <TD>galvanized iron</TD>
                                    <TD>0.015-0.017</TD>
                                 </TR>
                                 <TR>
                                    <TD>brass and glass</TD>
                                    <TD>0.009-0.013</TD>
                                 </TR>
                                 <TR>
                                    <TD><b>wood stave</b></TD>
                                 </TR>
                                 <TR>
                                    <TD><LI>small diameter</TD>
                                    <TD>0.011-0.012</TD>
                                 </TR>
                                 <TR>
                                    <TD><LI>large diameter</TD>
                                    <TD>0.012-0.013</TD>
                                 </TR>
                                 <TR>
                                    <TD><b>concrete</b></TD>
                                 </TR>
                                 <TR>
                                    <TD><LI>with rough joints</TD>
                                    <TD>0.016-0.017</TD>
                                 </TR>
                                 <TR>
                                    <TD><LI>dry mix, rough forms</TD>
                                    <TD>0.015-0.016</TD>
                                 </TR>
                                 <TR>
                                    <TD><LI>wet mix, steel forms</TD>
                                    <TD>0.012-0.014</TD>
                                 </TR>
                                 <TR>
                                    <TD><LI>very smooth, finished</TD>
                                    <TD>0.011-0.012</TD>
                                 </TR>
                                 <TR>
                                    <TD>vitrified sewer</TD>
                                    <TD>0.013-0.015</TD>
                                 </TR>
                                 <TR>
                                    <TD>common-clay drainage tile</TD>
                                    <TD>0.012-0.014</TD>
                                 </TR>
                                 <TR>
                                    <TD>asbestos</TD>
                                    <TD>0.011</TD>
                                 </TR>
                                 <TR>
                                    <TD>planed timber</TD>
                                    <TD>0.011</TD>
                                 </TR>
                                 <TR>
                                    <TD>canvas</TD>
                                    <TD>0.012</TD>
                                 </TR>
                                 <TR>
                                    <TD>unplaned timber</TD>
                                    <TD>0.014</TD>
                                 </TR>
                                 <TR>
                                    <TD>brick</TD>
                                    <TD>0.016</TD>
                                 </TR>
                                 <TR>
                                    <TD>rubble masonry</TD>
                                    <TD>0.017</TD>
                                 </TR>
                                 <TR>
                                    <TD>smooth earth</TD>
                                    <TD>0.018</TD>
                                 </TR>
                                 <TR>
                                    <TD>firm gravel</TD>
                                    <TD>0.023</TD>
                                 </TR>
                                 <TR>
                                    <TD>corrugated metal pipe</TD>
                                    <TD>0.022</TD>
                                 </TR>
                                 <TR>
                                    <TD>natural channels, good condition</TD>
                                    <TD>0.025</TD>
                                 </TR>
                                 <TR>
                                    <TD>natural channels with stones and weeds</TD>
                                    <TD>0.035</TD>
                                 </TR>
                                 <TR>
                                    <TD>very poor natural channels</TD>
                                    <TD>0.060</TD>
                                 </TR>
                                </TABLE></td>
                            </tr>
                         </table>
                        </FORM>
                        <div align=”right”><span class=”size10pt”>Copyright 1998
                         Donald R.Milam, PE </span> </div></td>
                    </tr>
                    <tr>
                     <td> <div align=”center” class=”size10pt”></div></td>
                    </tr>
                 </table>
{/source}

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