"; echo " onlinechannel01:    *** Error message 1 ***    Please enter only positive number for discharge.   Execution stops here. "; echo "
"; die; } } if($_POST["manningsn"] <= 0) { if($_POST["Submit"] == 'Calculate') { echo "





"; echo " onlinechannel01:    *** Error message 2 ***    Please enter only positive number for manning's n.   Execution stops here. "; echo "
"; die; } } if($_POST["bottomslope"] <= 0) { if($_POST["Submit"] == 'Calculate') { echo "





"; echo " onlinechannel01:    *** Error message 3 ***    Please enter only positive number for bottom slope.   Execution stops here. "; echo "
"; die; } } if($_POST["bottomwidth"] < 0) { if($_POST["Submit"] == 'Calculate') { echo "





"; echo " onlinechannel01:    *** Error message 4 ***    Please enter only nonnegative number for bottom width.   Execution stops here. "; echo "
"; die; } } if($_POST["sideslope"] < 0) { if($_POST["Submit"] == 'Calculate') { echo "





"; echo " onlinechannel01:    *** Error message 5 ***    Please enter only nonnegative number for side slope.   Execution stops here. "; echo "
"; die; } } if(($_POST["bottomwidth"] == 0) && ($_POST["sideslope"] == 0)) { if($_POST["Submit"] == 'Calculate') { echo "





"; echo " onlinechannel01:    *** Error message 6 ***    Bottom width and side slope cannot be zero at the same time.   Execution stops here. "; echo "
"; die; } } //set unit systems $unitsystems = 0; // default value if(isset($_POST["unitsystems"])) { $unitsystems = $_POST["unitsystems"]; } if ($unitsystems == 1) { $g= 32.17; $c= 1.486; $lengthunits = "ft"; $areaunits = "ft2"; $velocityunits = "fps"; $dischargeunits = "cfs "; $accelerationunits = "ft s-2"; $unitsystemsname = "U.S. Customary"; } elseif($unitsystems == 0) { $g = 9.81; $c = 1.0; $lengthunits = "m"; $velocityunits = "m s-1"; $areaunits = "m2"; $dischargeunits = "m3 s-1"; $accelerationunits = "m s-2"; $unitsystemsname = "SI (metric)"; } //main calculations $iflag= 0.; $kflag= 0.; $tol= 0.0001; $x = 0.; $dx = 1.; $q = $_POST["discharge"]; $b = $_POST["bottomwidth"]; $z = $_POST["sideslope"]; $s = $_POST["bottomslope"]; $xn = $_POST["manningsn"]; //main while loops while($kflag == 0) { $y = + pow(($x*(0.5*$b + 0.5*$z*$x)),2.5) - 0.5*pow(($q*$xn/(2*$c*pow($s,0.5))),1.5)*$b; $jflag = 0; while($jflag == 0) { if($y < 0.) { $x = $x + $dx; $jflag = 1; } else { while($iflag == 0) { $y = + pow(($x*(0.5*$b + 0.5*$z*$x)),2.5) - 0.5*pow(($q*$xn/(2*$c*pow($s,0.5))),1.5)*$b; $yp = + 1.25*$z*pow($x,2.5)*pow((0.5*$b + 0.5*$z*$x),1.5) - pow(($q*$xn/(2*$c*pow($s,0.5))),1.5)*pow((1 + pow($z,2)),0.5); $xr = $x - $y/$yp; if(abs($xr - $x) < $tol) { $iflag= 1; $jflag= 1; $kflag= 1; } $x = $xr; } } } } $yn = $x; $an = ($b + $z*$yn)*$yn; $pn = $b + 2*$yn*pow((1 + pow($z,2)),0.5); $tn = $b + 2*$z*$yn; $rn = $an/$pn; $vn = $q/$an; $dn = $an/$tn; $fn = $vn/(pow(($g*$dn),0.5)); } ?>


onlinechannel_01:   Normal depth in a prismatic channel

Definition sketch for a prismatic channel
Formulas

A = y(b + zy)
P = b + 2y(1 + z2)1/2
T = b + 2zy
R = A/P
D = A/T
Q = (C/n) AR2/3S1/2
V = Q/A
F = V/(gD)1/2
INPUT DATA:

Select:      

Flow discharge Q:        

Bottom width b:        

Side slope z:      

Bottom slope S:      

Manning's n:      

INTERMEDIATE CALCS:

Units selected:   

Gravitational acceleration g:   

Units constant C:   

Wetted perimeter P:   

Top width T:   

Flow area A:   

Hydraulic radius R:   

Hydraulic depth D:   

OUTPUT:

Normal flow depth yn:   

Normal flow velocity Vn:   

Normal Froude number Fn:   

            

  Your request was processed at "; echo " "; echo date('h:i:s a \o\n F jS, Y'); ?>    [  ].

Thank you for running onlinechannel_01.   Please call again.   [091005]

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