nozzle Definition and Topics - 23 Discussions

A nozzle is a device designed to control the direction or characteristics of a fluid flow (especially to increase velocity) as it exits (or enters) an enclosed chamber or pipe.
A nozzle is often a pipe or tube of varying cross sectional area, and it can be used to direct or modify the flow of a fluid (liquid or gas). Nozzles are frequently used to control the rate of flow, speed, direction, mass, shape, and/or the pressure of the stream that emerges from them. In a nozzle, the velocity of fluid increases at the expense of its pressure energy.

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  1. Anachronist

    B Beam of air: Extending the range of a fan

    If one Googles for "laminar flow nozzle", one finds many interesting tutorials on creating a nozzle for a laminar water jet; a stream of water that remains coherent over a long distance without breaking up. These typically consist of a large-diameter tube with regions inside (like sponges and...
  2. H

    Engineering Nozzle and diffuser momentum equation

  3. B

    Nozzle loss coefficient that increases with Reynolds number?

    Hi, I started to think about the drag coefficient of a sphere. At high Reynolds number Cd drops of suddenly when the boundary layer separates. If the Reynolds number is increased further, Cd increases with increasing Re. (I'm thinking about what is referred to as "post critical separated flow")...
  4. C

    Calculating the force from a pump + nozzle system

    I am attempting to calculate the force (in KgF) of a water pump + nozzle system. I have the pump curve (head vs. flow rate) for the pump, the diameter of the connection hose (2 inches) and the nozzle diameter (1 inch). The connection hose between the pump and nozzle is very short (approx 10 cm)...
  5. L

    I Misting system

    I am attaching a standard 5/8" garden hose with approximately 70psi pressure to a copper pipe that is capped on the opposite end with mist nozzles mounted periodically along its length. I want the pressure at each mister to be as similar as possible. The hose attaches at the base, a solid line...
  6. s4thishkmr

    How to manufacture this nozzle?

    Hi guys , Need help and suggestion in finding best way to manufacturing this nozzle. Thanks
  7. granzer

    Why variable geometry nozzles are not used on rocket engines

    Why is it that variable geometry nozzles, like those found on jet engine(iris nozzles), are not used as rocket nozzle to provide better altitude compensation?
  8. A

    Mass Flow Rate of Pressure Regulator

    Hey, I have an air tank that is at a set pressure, say 3000psi, and I have attached a regulator to the end that regulates the pressure down to 800psi. As the valve on the tank is opened the pressure and the mass in the container will decrease. If there was no regulator the mass flow rate would...
  9. A

    Air Tank Discharging Through A Nozzle - Unsteady Flow

    Hey, So I have a system where there is an air tank (0.2Litres @ 3000psi, 293K) and I have a convergent-divergent nozzle attached directly to it. What I want to know is an expression for how the mass flow rate varies with time as the mass in the tank decreases causing the pressure to decrease...
  10. B

    Trying to calculate the volume of gas flowing through a nozzle

    I've gone through many posts but haven't really come across something very clear. And on top of it my knowledge of fluid dynamics only extends to compressible fluids. I have a Nitrogen Cylinder Tank, with an exit pressure of 214.7 psia which is blocked by a solenoid valve at a location very...
  11. G

    Long mach nozzle shape

    Hi y'all, thanks in advance to anyone who knows a bit more about compressible/isentropic flow than me for the help, I have an interesting problem which I've been working on for a bit. Basically, I would like to measure species coming out of a reactor using molecular beam mass spectrometry...
  12. Nemo's

    What is the exit steam velocity?

    Homework Statement Steam, at 15 bar and 280oC, enters a nozzle with an initial velocity of 125 m/s. The steam enthalpy at the exit section is 2800 kJ/kg and the heat loss is 25 kJ/kg. What is the exit steam velocity?. Homework Equations 1)Qin - Qout = m [h2-h1+((c22-c12))/2] 2)h = Pv + u...
  13. S

    Volume flow rate variation of a free air jet

    Hi, I recently did an experiment whereby we investigated the velocity distribution of air expelled from a round nozzle whose diameter, D, was 30mm. We have been asked to calculate the volume flow rate at distances of 2D, 6D and 10D along the centreline. We found the flow rates to INCREASE...
  14. M

    Diesel injector sac pressure calculation

    I am trying to calculate the nozzle sac pressure required to deliver 60mm3/ms of diesel fuel into a pressurised cylinder (19MPa). The nozzle has 5 delivery holes of diameter 0.157mm and the discharge co-efficient is 0.87. The sac diameter= 0.7 mm and the sac volume= 0.12mm3. I have tried to use...
  15. N

    Enthalpy at the throat of the nozzle

    Hi, This is my first post in this forum :woot: I have a total enthalpy ht=3000 kj/kg with velocity at inlet v1=20 ms-1, Speed of sound a1=562.5 ms-1 and outlet pressure P2 = 1 bar With the formula ht=h*+(a*2/2) how do i calculate actual value at throat h* ? NOTE: (by trial and error) I can...
  16. needing

    Bernoulli effect at spray nozzle

    Hi. First post so I hope I have the correct thread location. I am reverse engineering a 40+ year old vertical slide carburettor design i.e. the venturi is horizontal. The current spray nozzle protudes vertically into the airflow but is straight sided and flat across the exit. Option 1...
  17. S

    Exit pressure of nozzle

    Hi There, Im studying thermodynamics at the moment and theres one statement about nozzles that I just haven't been able to understand. In my mind when a fluid exits a nozzle it would have a higher pressure than the inlet. Could someone please explain in what sense the pressure of a fluid drops...
  18. leafjerky

    Thermodynamics - Steady State Nozzle, find area of inlet/exit

    Homework Statement In a jet engine, a flow of air at 1000 K, 200 kPa, and 40 m/s enters a nozzle, where the air exits at 500 m/s and 90 kPa. What is the exit temperature, inlet area, and exit area, assuming no heat loss? Homework Equations min = mout = m where m = mass air flow dE/dt cv = Qcv...
  19. yangshi

    Choked flow out of air compressor and wind tunnels

    I posted this on Eng-tips and no replies yet:( I'm trying to design an as-simple-and-cheap-as-possible supersonic wind tunnel using an air compressor (this even possible? given the energy losses from shock waves...). I have access to a Porter-Cable 150psi, .8hp air compressor. Questions: 1...
  20. JP Beaulieu

    Venturi effect witout/with nozzle

    Hi, I am building a hose system with an automatic liquid dispenser using venturi effect. The 12v pump is taking water in a tank via a 3/4 pipe and has a capability of 2.9gpm at 50psi. The main system is built with 3/4 pipes and a 5/8 hose. The siphon pipe is 1/4 and I added a check valve...
  21. B

    Calculating Pressure Distribution in a Nozzle for Abaqus

    Hey all, So I have a small convergent nozzle that I'm modelling in Abaqus and I'm wondering how I could work out the pressure distribution so I can apply the correct load. The problem is I only know the pressure being fed to it by air compressor. Is there a way to use Bernoulli s or some other...
  22. S

    Nozzle problem between subsonic and supersonic speed & nozzle area

    Hi all, I have really a confusion between subsonic and supersonic speed evolution when the area decrease or increase I have a problem to understand why in supersonic regime the velocity evolution in a nozzle is adverse of the subsonic regime? for example in subsonic regime, when the area...
  23. M

    Water nozzle

    Good morning, I always walk on egg shells posting what is probably a redundant question on a forum. I have been reading for two days and there is a ton of physics information out there on the subject but most of it doesn't truly address the mechanics of what I am looking for. In a very...