Flow rate Definition and 464 Threads

Homework Statement A fireman's hose acting as a water cannon, directs 100 litres/s (100 kg/s) of water horizontally at your chest at speed 5 ms-1. Assuming water essentially falls to the ground after hitting your chest (rather than say reflecting horizontally backwards), what horizontal force...

Hi When I was writting my thesis I found in an article, published in International Journal of Heat and Mass Transfer, an unit of mass flow rate G - kg/(m^2*s). Isn´t it wrong? I think that the unit of mass flow rate is kg/s. Would you mind helping me to figure it out? Thanks.

Hi Friends, I am Milind Nachane, New member of PF. We have to buy a Water Treatment Device which eliminates the scaling and rusting Hazard. To decide model of device we need to know Flow rate of Pump. I know that Pump is Mono-block (Non-submersible) of 7.5 Hp and has 2 Inches Diameter...

I have a basic question for my own understanding of things, Consider a straight horizontal piece of Ø15 mm pipe (inside), 20 meters in length, with 5 bars static pressure connected to a water main. Trying to find out what the flow rate through the open end of the pipe will be, doesn't seem to...

Homework Statement If 5% of the heat available for steam production is lost to the atmosphere, determine the amount of steam raised per hour when the total flow of flue gases is 1400 kmol h-1. qmH = 1400 kmol h-1 Flue gas temperatures: Inlet = 1832°C Outlet = 300°C Water temperature: Inlet...

Homework Statement Homework Equations Bernoulli: p1+½ρU12+ρgz1=p2+½ρU22+ρgz2 Continuity: Q=U1A1=U2A2 Area=CC*(¼πd2) The Attempt at a Solution [/B] I attempted to apply the Bernoulli equation, making point 1 the top surface of the left hand side and point 2 the instant at the sharp edge...

I am having trouble understanding why blood flow rate is constant between the aorta and the sum of capillaries/sum of the arterioles. I keep thinking that in the arterioles or capillaries there is a decrease in velocity and somehow this decrease in velocity will decrease the total amount of...

I am working on something that I could use some help with. I have a flow sheet for some fuel injectors that gives fuel quantity through the injector with a set pressure and activation time for 4 different points with different activation times and pressures. I need to come up with a formula to...

Hi, I am not science student. Can anyone help me to solve this? Density and velocity of a fluid is given as 920kg/m3 and 5m/s, this fluid is flowing through an area of 25cm2. Calculate the mass flow rate? I am in search of some easy unite conversion tricks also.

So, I am new to here and I am currently a technician that does vacuum systems for the semiconductor industry (mainly Electrical). I came across something today that has me quite perplexed. So We have this system that flows gas through 1/4" stainless tubing to a pump to dilute gasses and...

Dear all, I'm wondering how a control valve can control pressure and flow rate. I understand that a control valve in a pipe induces a certain pressure drop but I don't understand how this affects flow rate. I'm disturbed with the continuity laws which states that the total flow rate between two...

How to convert volumetric flow rate to mass flow rate?

Hello! 1. Homework Statement I need to find the instantaneous height of a liquid during the simultaneous filling and emptying (through a hole) of a cylinder. I have varying Qin at incremental time of 1 sec. with cylinder area=5 cm and orifice area=0.5 cm. Homework Equations Torricelli's...

Homework Statement A fuel gas consists of 75% butane (C4H10), 10% propane (C3H8) and 15% butene (C4H8) by volume. It is to be fed to the combustion chamber in 10% excess air at 25°C, where it is completely burnt to carbon dioxide and water. The flue gases produced are to be used to generate 5...

I am not a mechanical engineer; but I have physics background. I want to lift about 250 watts of heat from a metal block. At the same time I have to maintain its temperature at 30 deg Cel. For this I want to use water-air heat exchanger (HE). Heat exchanger will have inlet & outlet pipes. Hot...

1. Homework Statement Hi. This is a problem related to designing a RC hover craft. We are given a datasheet for a fan used as thrust. http://imgur.com/6liZSid Sorry image post no working, url: http://imgur.com/a/6XLwL We have to approximate the equation to a straight line through the curve...

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...

Hi, We have a canister at a set pressure (4500psi) full of compressed air. A single stage pressure regulator is fitted to the canister that reduces the outlet pressure to 850psi. The flow from the regulator is then used in a divergent nozzle to create a thrust force capable of lifting a small...

Hello, We have a system with a 70 bar pump and 9 nozzles connected to the pump lines. Total flow rate is 2 l/m. Is there a way to change only one nozzle flow rate manually, with a pressure regulator valf just behind that nozzle? Thank you.

Good evening everyone, I have a pressure meter from where we determined a pressure drop of 5.5 psi (Initial pressure 45.5 psi, final pressure 40 psi). The working fluid is air. The diameter of one of the hoses that is connected to the pressure meter is 1/4". I wasn't able to take a picture of...

Hello, I am working with the mass flow rate equation which is:$$\frac{d \dot{m}}{dt}=\dot{m}_{in}-\dot{m}_{out}$$ To determine the change of the height of water in a reservoir. Assuming m_in = 10 and m_out = sqrt(20h), then : $$\frac{d (\rho \cdot Q) }{dt}=\rho \cdot Q_{in} - \rho\cdot...

If I have a tank of volume V, pressure P, and temperature T, what is the most effective way to determine the volume flow rate if I were to suddenly allow the air to discharge through a hose? My first thought was that I could use Boyle's Law to determine the compressed volume of air in the tank...

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...

Good afternoon all, I am doing some back of napkin calcs for work and am having trouble finding an answer (or one that I can understand--its been a while since undergrad). We have a valve that has particular flow rate requirements to prevent unseating the valve seal. This is a mass flow rate...

Hi i have calculated compressor , combustor , turbine inlet and outlet temperature , pressure so on and my output of gas turbine is 50MW , So for this i want to calculate the mass flow rate of air and fuel in compressor , combustor , turbine . Like m0=?,m1=?fan inlet,m2=? compressor inlet,m3=...

Homework Statement The tank in picture has section ##S_1## and it's linked with a tube of section ##S_2=\frac{1}{\sqrt{17}} S_1##. The tank is filled at an height ##h## and this level is kept constant by a sink ##R##, in such way that the exiting volumetric flow rate is ##Q=0.3 m^3/s## and...

hello! i was provided by the radii from 0 to 5 cm and a parabolic profile is also given .. in numeric form i was asked to calculate the flow rate how to understand it to solve further kindly help ...

Hi guys, First post on this forum. Greetings from the Netherlands :) I am currently in the process of designing a turbine used in locks in several canals. The turbine is powered when the lock chamber is being emptyed during the lockage. The goal is to calculate the water level in the lock...

I work in the oil and gas industry and frequently encounter an issue involving isolation valves that do not seal 100%, and that begs me to ask the following question... I often need to isolate particular sections of piping so that a segment can be opened/disassembled for maintenance. When I...

Hello, my first post here. I encounter a situation frequently at work that I'd like help with so here it is... When I isolate a particular section of pipe (by closing valves), I then bleed off the pressure in the isolated section (volume of isolated pipe varies from 3 cubic meters up to about...

I have a DIY project for a lawn sprinkler system but my flow rate is insufficient : if my setup is to work properly, the sprinkler manufacturer suggests a flow rate of 2880 litres per hour at a pressure no less than 2 psi. I measured the flow rate of my current garden faucet, which is connected...

Homework Statement calculate the flow rate at which oil (kinematic viscocity = (10^-6) (m^2) /s ) flow thru a cast iron pipe 100mm diameter and 115 m long under head difference of 5m Homework EquationsThe Attempt at a Solution hf = 32μLV / ρg(D^2) how to get the value of μ( dynamic viscosity)...

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...

Hey, Suppose you have an enclosed vessel that is full of water. You heat it up then you open a valve, and that will create enough thrust for it to act as a rocket. How much energy is needed for a steam rocket to get heated enough to achieve a mass flow rate of 2430 Kg/s. Mass of water= 256...

Homework Statement the equation of flow aret given is [(pi)((r_o)^4 ) / 8μ ] [-d/ds (ρ +yz ) ] , but the ans that i got is - [(pi)((r_o)^4 ) / 8μ ] [-d/ds (ρ +yz ) ] , what's wrong with my working ? Homework EquationsThe Attempt at a Solution

If wind was blowing through a tube at 15 kilometers an hour from an open end 2 meters wide to a tapered end only .3 meters wide how fast would the air be moving when it exits the pipe? I'm using the equation Q = v * A (Q is flow, v is velocity and A is area of the tube opening) but is that the...

Homework Statement Question: For a fluid flowing within a horizontal tube, if the diameter of the tube narrows, will the fluid's flow rate increase, resulting in increased pressure in the narrowing and explain your reasoning. Homework Equations Volume flow rate = volume/time Volume = Area x...

Hi everyone! As an experiment I am trying to calculate building my own PWC similar to a jetski assuming it is for sea level use. I really appreciate all detailed answers as I want to understand. The impeller will be installed under rear of craft, engine is mounted on top. Given Information...

Homework Statement " A horizontal water pipe has a radius of 10 cm and a pressure of 8*10^4 Pa at one end. At the other end the radius is 5 cm and the pressure is 6*10^4 Pa. What is the water flow rate through this pipe? Homework Equations P1 + 0.5 * ρ * v1^2 + h1ρg = P2 + 0.5 * ρ * v2^2 +...

Homework Statement I was told that the flow rate in open system at 2 points in the pipe system are not the same, is it true?? Homework EquationsThe Attempt at a Solution

(a) FIGURE 2 shows two cylindrical tanks interconnected with a pipe which has a valve that creates a constant resistance to flow of Rf when fully open. The height of liquid (of density ρ) in the first tank is hin and the second tank hout. The cross-sectional area of the first tank is Ain m^2 and...

Hello, I am new in this field, so maybe my questions will be stupid :) sorry for that :) In the company where I work, they measure flow rates of wastewater using Flow meter (Doppler device). The problem is, that the flow rate is very low, so this device is not submerged completely in the...

Homework Statement for part c , why when the vane is moving , the flow rate doesn't change ? ? Homework EquationsThe Attempt at a Solution The flow rate is given by the formula Q=Av , where A = area , v = velocity . IMO , when the velocity of vane change , the flow rate is no longer 0.687kg/s...

Hi everyone I searched about the mass flow rates and temperatures of exhaust gases of light gasoline internal combustion engine at different condition but I don't fond anything yet . Anyone can guide me? .

Homework Statement Hello everyone, I hope that you guys could lend me a hand. I need to calculate the heat loss at any point over a long pipe while considering lambda of the pipe. I am trying to use octave to find a reasonable flow-rate to keep the temperature loss to a minimum at a reasonable...

Homework Statement . Air, at a flow rate of 30 [N/s], flows through the reducer shown below. In the 300 [mm] diameter section of the pipe the specific weight of the air is 9.8 [N/m3 ]. When flowing through the reducer the pressure and temperature will fall causing the air to expand and...

I am trying to come up with a mathematical model so that, when the displacement of the plunger of a syringe is know, I can calculate the amount of a specific liquid in the barrel. Or the relationship between the speed of the plunger and flow rate at the tip of the needle (Again assuming that the...

Hi, First-timer here! I'm designing a physics project that involves pumping a certain pressure of air into an empty bottle. SETUP: The bottom of the bottle has a small hole through which a thumb tack fits tightly; the top (cap-side) has a valve through which the air is inserted. The bottle is...

Hi guys, I was wondering if you could help me with something. I work in the paper industry with what is called a suction roll. The roll has a rotating perforated steel cylinder with a stationary vacuum box on the inside and as the wet paper web travels over the surface of the roll, the vacuum...

Homework Statement what is G and γ mean here ? Homework EquationsThe Attempt at a Solution