The head losses (or accidental) are expressed s in heights of fluid (Meters) , in pascals or bars .

DH   is the loss of load meter column fluid

l is the coefficient of friction pressure drop or head losses

D H is the loss of load meter column fluid

V  is the average speed flow
 

• The pressure drop or head losses in networks ventilation or water arepressure losses caused by the passage of fluid barriers and accessories as valves, fittings, expansion, exit reservoir , hood etc.. .

• The head losses expressed in pascals or meter column of fluid (m) or m equivalent linear pressure drop. The head losses are also called accidental loss of loads. These are pressure losses due to elements encountered on the path of the fluid.

• The coefficients of pressure drop are given for these elements in experimental tables . In general these data are provided by the Manufacturers of hydraulic accessories . Some formulas are sometimes used to calculate these coefficients, as the formula of Weisbach for elbows or Lorenz cones diverging.

minor pressure drop editor,Table minor loss , Examples of internal flowspressure drop loss.htm,Hydraulic pressure drop in a valve

With MECAFLUX

The pressure drop coefficient of hundreds of Accessories of basic available in MECAFLUX and configurable . (eg closing angle valve hydraulics,angle of elbow ... )

The pressure drop coefficient is based on parameters you enter. the results sheet shows The coefficient of friction losses selected and the calculated load loss caused by the aerodynamics or hydraulic accessory you've chosen,.

The MECAFLUX interface of selection and setting of pressure drop in networks elements :

here Hydraulic pressure drop in a valve

calculation procedure with MECAFLUX :  

• select a ventilation or hydraulic accessory , choosing a "category" and a "element" ( + 56 basisc accessories miscellaneous items)
• Type parameters in the blue text area in "fluid parameters and components"
• click calculate

If a text box was not filled in correctly a message will indicate.

The results are given in meters of column fluid (Mcf) and pascals . (using the unit converter if necessary)

They are loaded in th 'Inventory to investigate all losses of a network.

You can add items to the list of elements if you klow them head losses coefficient.

E XAMPLES of data coefficients pressure drop of common accessories.

(MECAFLUX is delivred with data of basic accessories Ventilation and hydraulic configurable)

exemple: pressure drop of common accessories, in equivalent linear pressure drop