For an increased diameter and constant pressure, the volume flow of your fluid should be increased significantly. This is actually quite easy to calculate for newtonian fluids. However, as you describe your fluid as "glue", it may have all sorts of strange properties.

For an increased diameter and constant pressure, the volume flow of your fluid should be increased significantly. This is actually quite easy to calculate for newtonian fluids. However, as you describe your fluid as "glue", it may have all sorts of strange properties.

See the site in the attached link. It provides the equation and it also provides a calculator to compute fluid flow.

In short, flow rate depends on area of the nozzle, on delta pressure, on viscosity of the fluid (and also on the type of nozzle). For a constant delta pressure, increased area increases the flow. For a constant nozzle area, increasing delta pressure increases the flow. For a constant area and a constant delta pressure, reducing viscosity (they call it "density," or rho) increases the flow.

I'm not sure why "glue" would behave any differently from any other very viscous fluid.

Following links may help you

pls read them carefully

https://www.quora.com/In-a-water-flowing-pipeline-if-the-diameter-of-a-pipe-is-reduced-the-pressure-in-the-line-will-increase-Bernoullis-theorem-says-that-there-should-be-a-reduction-in-pressure-when-the-area-is-reduced-What-is-the-justification-for-this

https://sciencing.com/flow-rate-vs-pipe-size-7270380.html

Sir you can refer Poiseuille's law.

You can also refer this link, you may find this helpful.

https://physics.stackexchange.com/questions/22978/flow-rate-of-a-syringe

Practically, the flow rate increases . I try to carry out the experiment with a sealed super glue in the laboratory. I find out that 0.25mm opening rushed out faster than 0.20mm diameter opening.

There should be a significant increase in flow at increased pipe diameter with conventional fluids.

Since the fluid under consideration may have strange properties that may not align with conventional fluid flow.

There should be a significant increase in flow at increased pipe diameter with conventional fluids.

Since the fluid under consideration may have strange properties that may not align with conventional fluid flow.

Flow rate is equal to velocity into area keeping density constant. By increasing area it is obvious flow rate increases unless you have a change in pressure or flow velocity.

No. The flow rate / discharge increases when diameter increases.

For given pressure drop, mass density, and effective length, the square of the volumetric flow-rate, given by Bernoullis principle, is proportional to the diameter to the fifth divided by the friction factor.

For laminar flow, this reduces to the Hagen-Poiseuille equation, where the volumetric flow-rate is proportional to the diameter to the fourth.

And for turbulent flow (near constant friction factor), the volumetric flow rate is proportional to the diameter to 2.5.

The conclusion is that increasing the diameter by 25%, as indicated in the question will increase the volumetric flow rate approximately by a factor of 2.44 in the laminar flow-regime and 1.74 in the turbulent regime.

There should be some increase but not by any significant margin as such increase will also depend on viscosity of the glue given the size of discharge orifice. However, the response would be different for some other fluids such as water.

Dear Sheik Yaseen Boodoo! Probably it is a change in viscosity of glue, not a diameter influence. Viscosity is highly depends on temperature.

ofcourse, when you increase in diameter the flow rate is also incresease

In Situations where we can neglect the viscosity effect , and applying hagen-Poiseuille, we obtain the Formula relating the Pressure Gradient(DP) ,the volumetric flow rate(Q) and the area A of a section of a cylinder.

Q=(DP/(8*mi*Pi*L))*A2

Where L the length of the tube and mi the Viscosity. This means the that Q is proportional A2.

Now for your case Glue is a Viscous non Newtonian Fluid so the relation above cannot be applied as it is due to the presence of the stress and shear forces , but you will still observe a variation of the flow rate the depends of the section of your syringe but not only.

The volumetric or mass flow rate would increases due to the increase in Diameter at constant pressure... The volumetric flow rate is directly proportional to the area of the tip of the syringe and velocity of the fluid through the syringe... The area is in turn directly proportional to the square of the diameter of the syringe while the pressure is directly proportional to the velocity of fluid through the orifice of the syringe... Since the pressure is constant and the diameter increases, the volumetric flow rate would also increases...

Volumetric flow rate (mm3/s) = area of the tip of the syringe (mm2)* velocity of the fluid through the orifice of the syringe mm/s.. pressure applied = force applied / unit cross sectional area of the tip of the syringe ...... Force = mass of the load * acceleration of the mass of load on the fluid.. since the mass is in contact with the fluid, the mass applied on the fluid and the fluid have the same acceleration.... the force applied = mass of the load * ( velocity / time )..... Therefore pressure applied = (mass * velocity/ time)/ area..... However, Velocity of the fluid through the orifice = (Pressure applied * Area of the orifice of the syringe * time)/ mass of the load on the fluid= PAt/m..... This indicate that velocity of flow is directly proportional to the pressure..... Also Volumetric flow rate = Area of orifice * velocity of flow ... We have Volumetric flow rate = Area * PAt/m = PA^2t/m.......Using dimension analysis to verify the equation, we have Volumetric flow rate = A V=L^2* L/T= L^3/T..... PA^2t/m= (Force/ Area) A^2t/m = (MLT^-2/L^2) L^2^2*T/M=ML^-1L^ 4 T^-2 T / M = L^3/T..... Showing is dimensional balanced... Since the pressure, time and mass are unchanged in the experiment, while the diameter is increased thereby increasing the area then the volumetric flow rate would increased....

Then at what factor would the volumetric flow rate increases, we have: Vf2/Vf1= (P 2/P1) * (A^2)2/(A^2)1 * t2/t1 * m1/m2....... Since pressure, Mass's and time are constant and Area = pi d^2/ 4... We have Vf2/Vf1= (A ^2)2/(A^2)1 = (d^4)2/(d^4)1 = (0.25^4)/(0.2^4)= 2.441 .... Vf2= 2.441 Vf1.... As the diameter increases by a factor of 1.25 (from d2/d1= 1.25) the volumetric flow rate would be increasing by a factor of 2.441

Hi all

Assuming the glue to be a newtonian fluid and the flow regime to be laminar, various of the quantitative calculations presented are sound (e. g., Sverre). In this case, changing from D = 0.20 mm to D = 0.25 mm, the friction factor will drop due only to an increased Reynolds number (Moody Diagram). Now, if the flow is not laminar and the two needles are made with the same material (say, stainless steel), the relative rugosity of the larger needle will be less than that of the smaller one. For this reason, the flow rate in the larger needle will be slightly greater than those calculated. Of course, all this assuming the pressure at both needles’ entrances to be the same. However, I believe the glue is a non-newtonian shear-thinning fluid. In this case, the glue will flow in the larger needle under a greater mean deformation rate (or shear rate), that is, with smaller apparent viscosity. This, in turn, will increase the flow rate even more as compared to the effect of pure increased flow cross section considered initially.

Increase in diameter in a conduit under a constant pressure head will result in decrease in flow rate along the conduit length.

flow rate = volume X velocity

so in a given condition with increase of dia flow-rate will increase

Actually, I'm not sure about the glue case. However, it easy to notice that increasing the pipe diameter will increase the flow rate. In addition, other parameters should be taken into consideration such as pressure difference, pipe length, fluid viscosity (related to temperature as well, for example, the viscosity of water increases as the temperature decreases). You can find these information from Hagen-Poiseuille Law.

Best wishes.