Pressure Definition and 999 Threads

Hello everyone, Nowadays I am planning to redesign my centrifugal compressor which I designed for a subsystem in my graduation project. It's a 3D printed and brushless motor driven centrifugal compressor and its about a hand size. However, due to its relatively small size and relatively low RPM...

Was watching a video on the the Great Pyramid of Giza and it got me wondering how one might cut one of the stones. Doing a couple google searches, I thought that a Venturi pump would likely be the means by which the stones were cut. The problem being how would they get a large enough psi...

I was watching a YT video getting prepared for class this coming semester, and in the video, this diagram of a manometer was drawn (see image at end of message). The professor stated that the pressure in the tank (Pt) is = to the pressure at point A. Following this, he said that technically...

Kind of similar question was once on polish high school ("matura") exam, and the solution that the authors gave was: Pressure at the bottom of the chimney inside of it is ##p_{top}+\rho_1gh##, and outside ##p_{top}+\rho_2gh## where: ##p_{top}## is the atmospheric pressure at the height of ##h##...

Angle theta is different for every place at airfoil surface, so it can't be one theta from leading edge to trailing edge. Can please someone explain pressure integration in depth, step by step?

An airfoil section in a wind tunnel has many static ports/holes/taps on its upper and lower surface. These static ports can only read static pressure which acts perpendicularly to the local airfoil surface. In place A are static ports that read a pressure value of relative -100 Pa . This...

Ok, I am kind of lost in my fluid dynamics course on a specific topic. I understand the reynolds number and how it works. What i do not get:: if Re = VD/v, and if we increase V(velocity) which in turn will increase the inertial effects of the number, why is it called a pressure drag? pressure...

Hi, I have some measurements for pressure drop of Helium at room temperature and I would like to scale it to other temperatures. Taking into account that, i) the flow is turbulent, ii) the pressure drop, ##\Delta p##, happens always in the same piping and iii) there is only variation on the...

v=50m/s ∆Pg= -981Pa ∆𝑝𝑑 =490Pa c=1m 𝜌 = 1,225 kg m3 𝐹3 = ∫ ∆𝑝3 ∙ 1 ∙ 𝑑𝑥 𝑐 2 0 = ∆𝑝𝑔 ∫ 2∆𝑝𝑑 𝑐 𝑥𝑑𝑥 𝑐 2 0 = 2∆𝑝𝑑 𝑐 ∙ ( 𝑥 2 2 ) c⁄2 | 0 = 2∆𝑝𝑑 𝑐 ∙ 𝑐 2 4 ∙ 2 = ∆𝑝𝑑 ∙ 𝑐 4 = 490,5 ∙ 1 4 = 122,625 N Lift per unit of span = (F1) + (F2) +F3 + F4= 490.5+245.25+122,25+122,625=981N :confused: Pressure...

Hello, all. I am completely new here so please be gentle. I have a small, cylindrical, sealed ("no leak") pressure vessel with an approximate volume of 27 cm3. It has a constant supply of air pressure at 8"WC. I'm trying to figure out how big of a hole it can have if there is an allowable...

Having re-read "Dragon's Egg" recently, I recall that the cheela, being composed of degenerate matter, would explode if removed from their high-gravity environment and placed in freefall.* (For those who haven't read the story, the environment here is a half-solar mass neutron star with a...

I have following setup where a non-elastic belt is wrapped around an elastic object, like leather belt around waist. When I pull the belt with force F, it tightens around the elastic object and the belt exerts force to the elastic object. I would like to know what is the relationship between the...

Summary:: Could there be a place in a newly forming protoplanetary disc where the gas pressure and temperature would be anywhere close to survivable? I am writing a fiction story that takes place there, and I want to know how far from reality this premise would be. When a protoplanetary disc...

In Bernoulli's equation, you have static, dynamic, and hydrostatic pressures equal to a constant. In one sense, I'm wondering if the dynamic part of the equation explains this since -> Pressure = (1/2*rho*velocity^2) and pressure can be expressed as a force / unit area, therefore, an increase in...

Summary:: I can’t get the correct answers, I think I haven’t fully understand the theory behind them The answers are given in the picture

say for 3.013bar absolute pressure pressure ratio : P/Po = 14.7psi/43.707psi = 0.33 which means its chocked flow now i want to find diameter or area of orifice : so could anyone help me

I am currently doing an assignment on nuclear power and in the turbine, the steam is moving from pressure of 6Mpa to 0.008 Mpa. is there any way to work out the velocity of the steam when moving between these pressure differences?

I have just started this topic so i Don't have much clearity about it . In our school it was tought that Pavg = (Pi + Pf)/2 ...(i) If we have a cuboidal shape container then it should be pgh/2 ryt ? But also Pavg = Ftotal on the wall /A ...(ii) =...

Good day, all I have a K1600 motorcycle. Will an after market tire pressure sensor work on a 2014 GTL? Dealers are crazy expensive and was told today that they are on back order. After search the TPMS Sensor Guide, I've new tires ready to be mounted, but a little confused. Any help will be...

Work - Energy principle states that work of resultant force or sum of work of all forces acting on some system equals change in kinetic energy of the system. For inviscid fluid flowing in a pipe such theorem can be used to derive Bernoulli's equation because as fluid flows it is subjected to...

This is from Problem 7.45 of Thermal Physics by Daniel Schroeder.

I often see this set up in thermodynamic problems and need clarification on how Newton's Laws are involved for the piston: Gas inside a piston cylinder (1) is heated expanding the gas and raising the piston (initially at rest) to a height (2) in a constant pressure quasi-equilibrium process...

The correct answer is 5.6m, not sure where I made the mistake.

In the first figure, air goes forward and the can goes backward. My question is why does the air exert the pressure gradient force on the can. Can I have a hint for why the can doesn't move when air is being sucked in in the second photo.

So for a collection of particles each with mass m, the pressure beneath them, ##p(z)## should be higher than the pressure above them ##p(z + \Delta z)##. This is a change in force per unit area (force per unit volume I suppose) times a volume to equate with the gravitational force $$ \frac...

For an experiment where I must be able to control the pressure i attached to a syringe a 'chamber'. The inner diameter of the syringe is 19.3 mm and i will fill water to 17 cm of the syringe bottom (i call this P1), the spout has a inner diameter of 2 mm and a length of 2 mm (i call this P2) and...

Hi, here is my attempt... Feel free to correct me if I am doing it wrong. v1 = .8 m3 p1 = 250 or 250000 n/m2 p2 = 7000 or 7000000 n/m2 Cp = 1010 Cv = 7321. isothermally p1v1 = p2v2 [Boyle equality law (isothermal process)] 250 000 * .8 = 7000000 * v2 7000000 * v2 = 250 000 * .8...

Summary:: Basically the title: It seems that one of the formulas I use considers the pressure in PdV to be internal, when as far as I know, it is external. So to my understanding, in w = PdV, the pressure is the external pressure. However, I get tripped up because in my textbook, for a...

For an engineering project we have to make an energy storage system. We thought of something like a hydro dam. We were having a discussion about the pressure after the turbine in the hydro dam. The water immediately flows into the atmosphere ( so it falls down into a lake ). Can we then safely...

When we increase the pressure value to for ex 3, 5, ...100 bars the pressure increases. When the pressure is 1 we called it atmospheric pressure. My question is what's happening when the pressure is between 0 and 1; at 0 it's a vacuum. The idea is that I can't imagine it: if I am in a room...

I am a poor, dumb EE often stuck with the odd plumbing calculation. I am often asked questions like: "what size tubing do I need to convey 10 SLPM of 20 PSIG oxygen 200' with no more than 2 PSI pressure drop?" I generally treat the fluid as in-compressible and use Darcy-Weisbach (I like Bellos...

Hi, The problem I am working on requires me to work out the the pressure on the outer conductor of a coaxial cable due to the current on the inner one. This cable carries a dc current of 5000 Amps on the inner wire of radius 2 cm. The outer cylindrical wire of radius 5cm carries the return...

A container of 0.5l containing 6 moles of CO2 are heated to 200 ° C on is interested in explaining the pressure variations between the pressure of a perfect gas and the actual value measured on a pressure gauge. The coefficients of the real gas a=3.59 [atm l2/mol2-] b=0.0427 [l /mol] indicate...

Suppose we have specific amount of hydrogen gas enclosed inside a metallic chamber and that is connected to a very high positive voltage source. As the voltage is positive and that's so high that all the molecules inside the chamber lost their electrons and there is nothing but a nuclei gas is...

Hi all, I'm a tinkerer with no formal engineering background, but enjoy read about physics and engineering in general. I'm reading up on fluid flow and I'm a bit grasping at the concepts. As far as I understand it, flow rate, pressure drop and pipe size are all interrelated, where one affects...

Hello In a pharmaceutical lab,a certain pressure is applied to IV bags using the equipment shown below.We need to calculate the force acting on the bags based on the applied pressure.I know the formula is F=PxA.But i am not sure what the surface area is.Should i take the whole surface area of...

In a recent news article, a Frontiers Airline passenger became very unruly after two alcoholic drinks. On an airline flight, the only ones instructed on the combined effects of alcohol and altitude are the cabin crew. This is what the FAA has to say to them: Since issues related to alcohol...

Hi, I was reading about the pressure exerted by radiation and need help with few points. I'd appreciate if you could help me. Source: Proceedings of the American Academy of Arts and Sciences, Volume 38, By American Academy of Arts and Sciences , 1903 You can check this capture for more...

Diesel injector: How much pressure relative to the maximum combustion chamber pressure during the sharpest phase of detonation does an injector need to be able to overcome to inject its full charge? How much overlap is typical between injection and detonation? Water-tube boiler: Are the water...

Water is flowing in the pipe with velocity v0. Upon sudden closure of the valve at T, a pressure wave travels in the -ve x direction with speed c. The task is to find ##\alpha##, where ##\Delta P = \rho_0 c (\Delta v) \alpha##. The 1st step is to set up an equation using conservation of mass...

Hi all., Just hoping to get a better fundamental insight into a few things. If we start with this: http://hyperphysics.phy-astr.gsu.edu/hbase/Kinetic/vappre.html so we have a closed container at a given temperature, then we can find it's saturation pressure. All good so far. In the following...

I am interested to compare two scenarios relating to grip strength and how much horizontal pressure will be required to hold the weight. Scenario 1: You have a 20kg weight plate in one piece. You hold the plate between your fingers. Scenario 2: You are holding a small 2X4 block of wood with a...

There is a tall cylinder filled with water. And there is a 3 in diameter hole near the bottom and water is gushing out. (assume the cylinder is continually being re-filled from the top) You work to plug the hole with a 10 inch long cylinder that is exactly the perfect diameter fit to plug the...

I assume that air have ##1 kg/m^3## density. Therefore, using Bernoulli equation, on upside and downside of my test object, there is a differential pressure ##\Delta P##: $$\Delta P=0.5*(v_2^2 - v_1^2)$$ From cases: (a) ##v_1 = 1 m/s## and ##v_2 = 2 m/s##, then ##\Delta P = 1,5 Pa## (b) ##v_1 =...

Solution attempt : Option : I am sure that my work is wrong. But, I must add solution attempt in PF that's why I just added that. How can I solve the problem?

Summary:: Heat capacity for real gas with ideal gas (zero pressure) equation I'm looking at this problem and I'm stuck. I usually question everything but this problem is confusing me. I don't know how they've made the jump from reduced properties (from generalized Cp charts(?)) to...

Hallo. Since I'm new in this field, I hope someone can help me. I have a laminar, steady state, incompressible flow in a channel (a fully developed). Geometry of the channel is on the photo. How should I calculate the drop of static pressure across the channel? Since I have Re, I did calculate...

What could be the water pressure under the ice of Europe moon? Could it be toleratable for not super expensive machines, structures?

Hello everyone, I would appreciate any help with my task I am struggling to resolve. I need to calculate or simulate pressure drop when got the following parameters: 1. Supply pressure: 45barg. 2. Pipe Length: 80 meters 3. Pipe diameter: OD - 10mm, ID - 8mm. 4. Pipe material: stainless steel...