Science topics: ThermodynamicsPressure

Science topic

# Pressure - Science topic

A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)

Questions related to Pressure

Want to compare FEM results to gain confidence.

Assuming cylinder pressure data is available what is the best way to model NOx?

Pressure variation of superconducting state parameters.

Hello,

I would like to know whether there is a general dependence of the boiling temperature of a liquid on the surrounding pressure? I am trying to determine by how much I should decrease the pressure in order for the liquid to boil at a temperature below its boiling point.

whether the Refractive index of piezoelectric materials (Example: Polyvinylidene fluoride-PVDF ) changes by the application of pressure, strain or force ?

While giving inlet Boundary conditions(In Ansys work bench under fluent) as velocity inlet and outlet as pressure outlet, please note that the default value of gauge pressure is zero.

1) What does it signifies?

2) Assume that if water inlet and outlet source is a common open vessel what should be the value of it?

3) Please also note that if you set a value at inlet or outlet of a pipe the pressure value is fixed, then how to determine pressure drop for a given velocity inlet?

any info will be of great help?

With the increase in shock layer temperature, how is the pressure and density of shock layer going to change?

Both magnitude of a pressure and mass flow rate of any fluid is affected by the geometry of flowing in and out.

Any book or paper which has lots of examples to show pressure drop and discharge for various geometry will be of great help.

like i can built a small pump with some plastic tube where pressure can be changed accordingly.

The plasma temperature is usually found to decrease with increasing the gas pressure. Did any one see the opposite behavior in any experiment specially the cold plasma like glow discharge for example? What might be the reasons?

What is the effect of pressure on foamability?

I am wondering what is the effect of pressure on foam generated by sparging (bubbling)?

Suppose for some quantity x we have a derivative with respect to temperature (dx/dT)

_{P}, i.e. at constant pressure. Can we somehow link it to a derivative with respect to volume, at, let’s say, constant temperature, i.e. (dx/dV)_{T}? This is just an example and I’m wondering, maybe there are some universal rules, which enable to perform such substitutions?To simulate a pressure driven flow in a complex geometry like porous media, usually the constant body-force has been used.

Why the development of the force field is simply neglected? Does not make sense?

In my point of view, the pressure field will develop based on the geometry while a body force like gravity would act on every liquid molecule the same every where.

How NS handles this situation?

deflection due to wind pressure

As we know water in soil, especially fine grained soil which has been shown to be able to sustain very high tension. So, I would like to know the plausible explanation for the high water tension (much greater than 100 kPa pressure, commonly consider cavitation pressure) that has been directly measured in soils

I would like to know if there is a way to

**calculate**the**temperature rise and**hence the**wear rate**of two bodies in**sliding contact****theoretically**?The data I have are contact pressure, sliding surface are, sliding velocity, and details about the material in contact.

I wanted to prepare a pellet from a powder using a uniaxial press and a matrix attached to a pump, but with the pressure and the holding time that I have chosen, the pellet obtained breaks up.

Are there a way to determine the correct pressure and holding time before launching tests?

I have an acrylic cylindrical tube which is closed at one end and other end applying fluid pressure.

Hi, I got a grid with logarithmic refinement and I need to sectorize a sub-cell from the principal cell, when I tried it, CMG sectorized all the cell not the sub-cell that I need. Is a 9*9 refinement, and I need to obtain pressure data from the sub cell 5 5 1.

I want to study the effect of "Pressure on the kinetics of diffusion" in diffusion bonding between Al and Ni.

I want to solve a CFD problem.

the inlet of my domain is connected to the Specified pump so my flow pressure and flow rate are known,

for modeling the inlet boundary condition I have two options (I use fluent software)

velocity or pressure inlet Bc

With velocity inlet bc, I have correct flow rate but my pressure is incorrect, and when I use pressure inlet bc I have correct pressure, but this time my flow rate is incorrect, so what can I do? and what is the best boundary conditions for my inlet?

Thank you

I want to make CO and Si thin films. I am using 29w,30 sccm,Ar,1.8E-1 pressure.

but the plasma is not seen .

The flow rate and input power of positive displacement pumps are varying with speed. Is there any variation in input power when the pressure difference or load is increasing at constant speed?

Hi to everyone,

I am trying to simulate cavitation inside nozzle with kOmega SST turbulence model using interPhaseChangeFoam (at least for this case).When i run the case, after 40 or 50 time-steps always giving following floating point error:

smoothSolver: Solving for alpha.water, Initial residual = 4.1184e-06, Final residual = 3.80347e-09, No Iterations 1

Phase-1 volume fraction = 0.98612 Min(alpha1) = 0.000310125 Max(alpha1) = 1

MULES: Correcting alpha.water

MULES: Correcting alpha.water

Liquid phase volume fraction = 0.98612 Min(alpha1) = 0.000310125 Max(alpha1) = 1

smoothSolver: Solving for Ux, Initial residual = 1.98514e-05, Final residual = 1.02782e-09, No Iterations 2

smoothSolver: Solving for Uy, Initial residual = 5.44074e-06, Final residual = 1.94705e-10, No Iterations 2

smoothSolver: Solving for Uz, Initial residual = 8.8507e-05, Final residual = 3.80435e-09, No Iterations 2

GAMG: Solving for p_rgh, Initial residual = 2.79212e-08, Final residual = 2.04895e-10, No Iterations 1

GAMG: Solving for p_rgh, Initial residual = 6.59936e-09, Final residual = 6.59936e-09, No Iterations 0

GAMG: Solving for p_rgh, Initial residual = 6.61102e-09, Final residual = 6.61102e-09, No Iterations 0

GAMGPCG: Solving for p_rgh, Initial residual = 6.61138e-09, Final residual = 6.61138e-09, No Iterations 0

smoothSolver: Solving for omega, Initial residual = 5.4048e-06, Final residual = 6.75835e-10, No Iterations 2

smoothSolver: Solving for k, Initial residual = 9.03591e-06, Final residual = 2.43949e-09, No Iterations 2

ExecutionTime = 97153.3 s ClockTime = 98393 s

Max pressure: 323086

Min pressure: -35072.5

Max velocity: 28.9586

Min velocity: 0

Courant Number mean: 0.00779459 max: 0.0996774

deltaT = 3.50877e-08

Time = 0.01051926

smoothSolver: Solving for alpha.water, Initial residual = 4.11863e-06, Final residual = 3.80331e-09, No Iterations 1

Phase-1 volume fraction = 0.986119 Min(alpha1) = 0.000310159 Max(alpha1) = 1

MULES: Correcting alpha.water

MULES: Correcting alpha.water

Liquid phase volume fraction = 0.986119 Min(alpha1) = 0.000310159 Max(alpha1) = 1

smoothSolver: Solving for Ux, Initial residual = 1.98021e-05, Final residual = 1.02634e-09, No Iterations 2

smoothSolver: Solving for Uy, Initial residual = 5.44207e-06, Final residual = 1.94729e-10, No Iterations 2

smoothSolver: Solving for Uz, Initial residual = 8.84228e-05, Final residual = 3.80449e-09, No Iterations 2

GAMG: Solving for p_rgh, Initial residual = 2.58283e-08, Final residual = 1.86337e-10, No Iterations 1

[5] #0 Foam::error::printStack(Foam::Ostream&) at ??:?

[5] #1 Foam::sigFpe::sigHandler(int) at ??:?

[5] #2 in "/lib/x86_64-linux-gnu/libc.so.6"

[5] #3 Foam::divide(Foam::Field<double>&, Foam::UList<double> const&, Foam::UList<double> const&) at ??:?

[5] #4 Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> > Foam::operator/<Foam::fvPatchField, Foam::volMesh>(Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> > const&, Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> > const&) at ??:?

[5] #5 Foam::phaseChangeTwoPhaseMixtures::SchnerrSauer::pCoeff(Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&) const at ??:?

[5] #6 Foam::phaseChangeTwoPhaseMixtures::SchnerrSauer::mDotP() const at ??:?

[5] #7 Foam::phaseChangeTwoPhaseMixture::vDotP() const at ??:?

[5] #8

[5] at ??:?

[5] #9 __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6"

[5] #10

[5] at ??:?

[baris-desktop:10415] *** Process received signal ***

[baris-desktop:10415] Signal: Floating point exception (8)

[baris-desktop:10415] Signal code: (-6)

[baris-desktop:10415] Failing at address: 0x3e8000028af

[baris-desktop:10415] [ 0] /lib/x86_64-linux-gnu/libc.so.6(+0x36d40) [0x7ff21608cd40]

[baris-desktop:10415] [ 1] /lib/x86_64-linux-gnu/libc.so.6(gsignal+0x39) [0x7ff21608ccc9]

[baris-desktop:10415] [ 2] /lib/x86_64-linux-gnu/libc.so.6(+0x36d40) [0x7ff21608cd40]

[baris-desktop:10415] [ 3] /home/baris/OpenFOAM/OpenFOAM-2.3.1/platforms/linux64GccDPOpt/lib/libOpenFOAM.so(_ZN4Foam6divideERNS_5FieldIdEERKNS_5UListIdEES6_+0xd5) [0x7ff21734cc05]

[baris-desktop:10415] [ 4] /home/baris/OpenFOAM/baris-2.3.1/platforms/linux64GccDPOpt/lib/libphaseChangeTwoPhaseMixtures.so(_ZN4FoamdvINS_12fvPatchFieldENS_7volMeshEEENS_3tmpINS_14GeometricFieldIdT_T0_EEEERKS8_SA_+0x19b) [0x7ff21ae2aaab]

[baris-desktop:10415] [ 5] /home/baris/OpenFOAM/baris-2.3.1/platforms/linux64GccDPOpt/lib/libphaseChangeTwoPhaseMixtures.so(_ZNK4Foam27phaseChangeTwoPhaseMixtures12SchnerrSauer6pCoeffERKNS_14GeometricFieldIdNS_12fvPatchFieldENS_7volMeshEEE+0x33c) [0x7ff21ae2f3cc]

[baris-desktop:10415] [ 6] /home/baris/OpenFOAM/baris-2.3.1/platforms/linux64GccDPOpt/lib/libphaseChangeTwoPhaseMixtures.so(_ZNK4Foam27phaseChangeTwoPhaseMixtures12SchnerrSauer5mDotPEv+0xff) [0x7ff21ae2ff8f]

[baris-desktop:10415] [ 7] /home/baris/OpenFOAM/baris-2.3.1/platforms/linux64GccDPOpt/lib/libphaseChangeTwoPhaseMixtures.so(_ZNK4Foam26phaseChangeTwoPhaseMixture5vDotPEv+0xa2) [0x7ff21ae18242]

[baris-desktop:10415] [ 8] MRinterPhaseChangeFoam() [0x431350]

[baris-desktop:10415] [ 9] /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf5) [0x7ff216077ec5]

[baris-desktop:10415] [10] MRinterPhaseChangeFoam() [0x433792]

[baris-desktop:10415] *** End of error message ***

When I check the results of Pressure, velocity and α distributions seem OK? What I did is:

==> Run the case single and parallel (nothing changed same problem)

==> Increased the mesh number gradually (Still same problem)

==> Change initial conditions, schemes of k and omega (nothing changed)

==>Tried with RNGkeps model. (Fortunately it worked)

==>As a result, i recognized that I am getting this floating error since Omega value is excessively high.

So, does anyone have any idea why it happens? By the way, is there anyone who already obtained good result with kOmegaSST using multiphase solvers of OpenFOAM?

Thanks in advance.

Baris

In his "Treaties on thermodynamics" Max Planck derives an expression for the specific heat at constant pressure. I attached a screenshot of his derivation from the book. I do not understand how the third formula, in which he substitutes (du/dtheta)_p, is derived. I really would appreciate if someone could help me to understand this relation.

The definitions of the symbols are:

c_p ... specific heat at constant pressure

u ... inner energy

theta ... temperature

p ... pressure

v ... volume

I also attached a link to the book where you can find the complete derivation on page 56.

btw: I actually read a hard copy of the book. For this question I searched for an online pdf of the book and found this one. The version I found contained the handwritten notes on the right side. So there was someone before who had this question.

I need to know the density of water steam in the Temperature interval 1273 K-1873 K and Pressure interval 0.1-300 MPa. I didn't find anything for pressures higher than 10 MPa and temperatures higher than 1273 K. Any suggestions?

Hi every body. As you know at CNG stations, Turbine meter location is before of compressor. my purpose is to know how this pulsations, affect the accuracy of this turbine, while the gas flow is In the opposite direction.

Hello!

I am trying to study fatigue properties of polymer tubes due to cyclic internal pressure. Any help regarding a system that could enable me to produce this type of pressure would be really appreciated.

Thanks,

Sia

Neutral markers provide insight into levels of variation but do not take into account selective environmental pressures of a species and therefore do not provide information in an evolutionary context as would the use of non-neutral markers.

Is there any key significance or insight in using a neutral and non-neutral marker in conjunction for a population genetic study?

hi

i work at modeling of thermoacoustic phenomenon in rijke tube with ansys fluent

i want to show pressure oscillation in this phenomenon

i modeled a tube with 1m length and include just one segment of heat convertor

then i run steady-state solution with p(inlet)=0.5 and p(outlet)=0

and wall temprature (tempratue of heat convertor)=3000k

and when this solution convergenced next step is imposed pressure pulse at outlet such as p=30sin(2*pi*f*t) with udf for 2000 time step with time step 1e-5

and then change pout=0 and run transient solution for 100000 time step with time step=1e-5

i cant see any oscillation in pressure

anyone can help me?

thanks

What is the material of the sensor used in continuous indiect type tyre pressure monotoring system?

hi

i need the 3d profile dynamic air blast pressure in a non venting confinement.

who can help or addressed me about it?

Hi,

I found that the contact pressure is reported to be zero for a bonded contact and non zero (nearly equal to normal stress) for a frictional mate. Why is it so? Why doesn't it report 'the contact pressure' in case of bonded contact?

I read in link below that contact pressure = contact stiffness*contact penetration. Does this mean it represents how bad the contacts penetrate? Or it really does reflect contact pressure?

Any color-changing or other variation by pressure or other stimulus

if flow at the inlet of the pipe is 1m/s and at the exit the pressure is zero bar. i wanted to study the flow behaviour at the exit of the pipe.

Hi

I want to heat my substrate up to 400C in vacuum around 5E-4 Torr and in argon gas in 5E-2Torr. What are the characteristics of heater that I should consider in these pressures? What are good materials for such goals and of course they must be cheap.

thanks

masoud

I am currently designing the hydraulic system of a refuse compactor vehicle. I'm having a problem in choosing the correct method to choose the best working pressure and temperature in order to produce high efficiency.

I am working on turbulence. I actually want to know about the significance of pressure spectrum in practical application.

Does any body know about pressure spectrum and it's application?

Thanks.

We know that all element have sensitivity due to temperature.

Which element has the most sensitivity?

d (density)/ d (temp)= MAX

Hello everybody!

How can it be possible to feel no pain in a full-squat, but feel pain in the knee when deadlifting with a wider stance (Sumo-deadlift)? Is the pressure on the meniscus greater when greater abduction occurs in the hips?

Anyone have any idea on how to harvest the acoustic energy from a line sound source? The line sound source is in small scale, maybe in a centimeter range, and the sound pressure is very small, around uPa I guess.

Greeting.

I have a Capillary Electrophoresis Agilent G1600 (3D CE system) that has been having problems lately. The system can not achieve stable pressure and crashes afterwards with the errors 5207 and 5210.

In the logbook, it says to check bottle and screws for fitting. I have done this and the errors still occurs.

Can some help me?

I don´t have the Service Diagnostic Disk. Can someone provide it for me? Or give me the link to it?

Thank you very much

I used the Widom test particle method to calculate the chemical potential. The chemical potential I get for gaseous phase is consistent with literature. However, the value for denser phase is consistently lower especially at lower temperature. All other variables, internal energy, pressure, density seem OK. I am really confused with this.

Dear all,

The constitute model is mooney-rivlin, C1=0.004,C2=0.016,D1=0, or I even tried a simple one: a linear elastic model with poisson's ratio 0.49. Since the material is very soft, I confront the convergence issue that I want to add a big pressure like around 5MPa on it but it diverge when the pressure reach 0.3MPa. For the geometry, just consider simple cantilever beam. The warning always shows Excessive distortion at a total of XXX integration points in solid elements. And I have tried refine the mesh and change mesh element type, it does not work.

Really feel appreciated if someone could help.

Is there any method for multi-zone combustion modeling in diesel engines using experimental in-cylinder data like cyclic variation of temperature, heat flux or pressure? Please let me know the procedures and study contents.

i want to analysis a plate problem with uniformly distributed load by meshless collocation method. the unit of uniformly distributed load in the equation of plate is (N/m^2) but the unit of the applied force on per node is (N), i want to know what force is applied to each node?

Hi

How can one get the relationship between pressure & adiabatic compressibility of a

**liquid**when the graph of temperature vs adiabatic compressibility is known ?TIA

I've done an experiment and there's a problem because of different atmospheric pressure for different days of experiment. It is quite large that effects my analysis. How can I overcome this problem?

Examples: The first day of exp: 101250 atm Pressure. The second day: 101590 atm Pressure. This will effect the total pressure for wind tunnel experiment. How can I overcome this type of problem? Any idea?

I am starting a project to review the Integrated Production Modeling approach in one area of our field. I think is the best way to evaluate the effect of flowing pressure (or back pressure) on the rate and hence improve accuracy of Type Curves. It is also a good way to evaluate the production network under actual operational constraints. Is there anyone doing something similar?

I need Physical and chemical properties for L-arginine like critical temperature, critical pressure and critical volume. Thanks.

I need HTC values for different water pressures or water velocities as mentioned in the attached article.

I am commingling production at the surface, and I am trying to determine the order in which to open the wells so that the high pressure wells will not flow into those of lower pressure. (Picture attached for further explanation)

Should I open the well of highest pressure first and wait for its pressure to decrease before opening the second, or should I choke all wells to make their pressures equal to that of the lowest pressure well? Is there a standard equation that I can apply to each situation (given initial pressures, IDs, and flow rates) that can allow me to compare the overall final flow rate?

Like which geometry and arrangement of perforations can reduce the pressure drop?

The perforated plate is used as an element in flame arrestor. So i want to know which arrangement of perforations reduces the pressure drop across the element

When using the Acetonitrile (HPLC grade) (100% Pump B) for long time, there is pressure variation in Pump A & B.

Now I solving this problem by ultra sonication of Pumb B filter.

How can we prevent joule Thomson effect on valves (natural gas plant)? and how should we deal with this effect in case it happen to a valve (pressure drop)? is there any procedure regard this matter?

Dear all,

to study the effect of pressure on the structural properties, I suppose that there is a relation between lattice parameter A and pression P. I want to know this relation please.

Thanks

We need the vapour pressure curve for Bis(ethycyclopentadienyl)magnesium metalorganic.

α = (po-pt) / (p0-peq)

Where, p0 is the initial pressure, pt is the pressure at time t and peq is the final equilibrium pressure.

What should be the most easiest approach to analyse foot pressure and knee loading during osteoarthritis? Any software for analysis of it?

Is there a way to measure the pressure in the coronary artery?

I see temperature but what pressure and humidity did you have?

Conference Paper Characterization of Aging Effects in Lead Free Solder Joints...

My initial and final pressures are 1.45 atm but the pressure fluctuates from approximately -3200 to +1500 atm! What is my fault? My fix command is:

fix NPT all npt temp 93.7 93.7 50 iso 1.45 1.45 100000

There are several possibilities for the realization of the pressure load.

For example, when I apply a pressure to an area (lets say, thin rectangular plate) the area of the plate grows during the deformation process. One possibility is to keep the pressure per unit area constant (in this case the total force acting on a plate grows during the deformation) and the second is to keep constant the total force acting on the plate (in this case the force per unit area decreases with the deformation). I looked through the help, but I wasn't able to find which option is chosen in ANSYS. I would appreciate any hints.

Could you give me some reference? On the Q. and reference on pop ratio for both of them? Or the answer of the Q is the best?

I am working on enhancement of heat transfer in a square channel through broken ribs. I need to calculate friction factor f so I need pressure drop across the periodic duct. I am using FLUENT 6.3.26 for simulation with periodic and symmetric conditions. The upper and lower walls are heated walls where constant heat flux of 2500 W/m2 is applied and other two walls are adiabatic, and adiabatic ribs were provided on heated walls. I am using the k-ep turbulence model. Is there any other method to calculate friction factor in this case?

How can sensor charge produced by the steady pressure be held for a longer duration?

What kind of signal conditioning circuitry I can implement?

Here is the sensor product link:

This instrument shows the pressure frequency at one point.

I have a basic doubt regarding Bernoulli's Theorem. Assume a constant area pipe with P1 pressure at inlet and Patm pressure at outlet. Assuming inviscid flwo and applying Bernoulli's theorem, how does pressure varies along the length of the pipe. P1 > Patm. Now the doubt is since area is same using continuity equation velocity has to be same at all points along the length of the pipe. P1 + 0.5 rho V1^2= Patm+0.5 rho Vexit^2 (Assuming levels are same) This gives P1=Patm. Please help!!!!

I want to model a helical pipe and I have oscillating pressure gradient boundary condition. Now my question is how can I apply this boundary in commercial codes (FLUENT,CFX,...) and if I can't solve this with these codes what should I do?

I am currently studying gait and posture analysis. What are the factors that you need to consider while dealing with pressure sensors? (Example: type of sensors used in force platforms)

I'm using ammonia as a reagent gas for chemical ionization MS. Set at 2 bar, the pressure on the pressure reducer drops during a series of analyses to -1 bar, resulting in a drop from 1.5 mL/min flow to a steady 0.4 mL/min. Of course, this non-optimal flow yields serious losses in sensitivity and inconsistent measurements.

The pressure reducer is suited for ammonia and two types have been tested, the tubing has a large amount of windings stacked in a vertical position and was replaced by a longer one, and even the entire module with mass flow controller and valves inside the MS was replaced. No results. The technicians from both the MS company and from the gas supplier do not see the cause.

Has anyone experienced similar issues, or does anyone have an idea about potential solutions to this problem?

The diameter of the plate is 140mm, while the diameter of the perforation is 3mm. I want to calculate the pressure drop for various flow rates.

I want to use a water lute to balance the pressure in a CVD instrument, the pressure in the chamber is increasing from 1 Pa to more than 1 atm, because this instrument will leak higher than 1 atm, so I have to open the valve before the pressure reach 1 atm, e.g 0.9 atm, and also make sure there is no air bubbles at the water lute valve position or the air will leak into the chamber.

Is there any specialist who can help me design a new water lute valve? Can I use a ball valve at the water lute position to seal the water and the vacuum in the beginning when the pressure is about 1 Pa?

What about other materials with high vapour pressure in room temperature (eg. In,Sb,Sn,Pb)?

In adiabatic flame temperature formula, the molar heat capacity of products at constant pressure has equation for each compound. Do I need to calculate the average compound? At what temperature should I calculate for each compound?

T(ad)=T(0) + H (enthalpy changes due to combustion)/ C(p)

I'm after a sensor to measure the difference in pressure between two areas of flow. Can anyone direct me to a sensor I can buy, or schematics to construct one? I want to measure the difference in pressure between the stream bed surface and subsurface. Thanks in advance

Is there any standard method available to model the same for hydraulic systems?

Hi

Dear friends.

I'm trying model a simple rectangular channel steady-state flow on Fluent by VOF: open channel condition.

Something cause a problem and affect the results.

the geometry of my channel is 30x30cm by 0.002 slope which the channel length is 10 m ; and the flow depth is 10cm.

According to the

and

boundary conditions considered as pressure- inlet &outlet and the top of my channel considered as pressure inlet according to the Fluent Help!

I've tried many B.C. to all the boundaries. but the velocity of air at the inlet considered about 90m/s!!!!! which it increases along the channel to end and reaches to 690m/s!!!!!!!!!!!

how can it possible???? and i cant fix it

also, density reports shows the water (Secondary phase) is under the air (First phase), which it is true.

but the main problem is the air velocity in Domain. Pics.>>>>>

Please help me to solve this problem.

The co-relation between the foot pressure and the knee back injury risk. Any valuable suggestions and evidence based studies available?

I am aware of the individual definitions of both static and absolute pressure.

Will the magnitude of static and absolute pressure be the same, even though definition wise they represent different concepts?

(e.g., high-Ba-Sr granitoids, low-silica adakites)

I know that plagioclase in the source, and its pressure dependence play an important role on it, but there is no plagioclase in mantle rocks, is there?

I mean other things without the pressure and pipe diameter.

A method to measure the surface tension of a liquid, relies on creating an air bubble beneath the surface of the liquid, (see diagram). A syringe needle (circular in section) with a sharp tip of a known radius is used to form the air bubble.

How and why can the maximum pressure exerted in forming the bubble be related directly back to the surface tension ?

I am doing triaxials tests on fine sand (Leighton Buzzard, fraction E, particle size distribution 90-150 um). Sample dimentions are 50 x 100 mm. At the top and bottom of my sample I put a saturated

**stone porous discs**. Applied isotopic, confining pressure is 70 kPa and back pressure is 50 kPa.How can I estimate time needed to saturate my sample using calculation of the Darcy's law? Is there any method to measure the permeability of this porous discs?

I have attached the photo how this disk looks like. I cannot find any information at the manufacture's website. Any advice or previous experience would be really helpful!

Thanks,

Aleksandra

I am considering there is small asymmetry of right left leptons in the early universe due to some reason.

Are there any reliable and valid measurement tools?

I have heard of pressure gauges, but no other measurement tool.

How does band gap structure change under pressure?

I have question regarding band gap structure of semiconductors.

I would like to know what sort of pressure sensors are appropriate for measuring the nasal pressure?

How can I model the evaporation loss or calculate the evaporation rate from subcooled boiling water in a closed vessel?

I would like to model an evaporation process realizing in a closed vessel which is initially filled with a preheated water having a temperature of 80°C. About 3/4 of the vessel is filled with water, and the remaining portion is naturally filled by air with a relative humidity of 20%. The water is heated gradually up to the boiling temperature of 100°C at 1 atm. At this time interval, mass transfer occurs at the liquid-gas interface due to diffusion and some of the water is evaporated until the water boils. It is known that the evaporation rate will change with time during this process. When the boiling temperature reaches 100°C, the pressure valve opens by periodically allowing some steam to escape to keep the pressure inside the vessel at 1 atm , thus preventing any excess pressure buildup. In the light of the given knowledge, how to model the process for calculating the evaporation loss.
Regards.

It is a rarely used method in our institution and if aspirated what are the adverse effects expected and what are the early signs to identify the complications?

I need to determine theoretically pressure drop for a multi-channel cold-plate across input and output for a single phase liquid. I have referred poiseuille number equation for the pressure drop, but those are for cylindrical shape channels. The channel for which i want to find out pressure drop is in serpentine shape, where length, width, depth are variables.

And please note that ends of channel are not sharp they have an arc profile.

Any information in context with the matter will be really helpful.

I want to know how these kinds of modes created and what is the source of this kind of modes.

How can I measure the hydrodynamic pressure drop in a microchannel due to a single droplet?

Is there a formula to calculate the Hydrodynamic pressure drop in a microchannel due to a single droplet in a two phase flow with continuous or on demand droplet generation?

Is there anyone who is working with ONYX-3 Magnetron Sputtering Cathode? i meet some problems with plasma generation: i measure a current without having a plasma even if i use the appropriate Argon gas at the appropriate pressure 10-2 mbar! Thanks for Help

The effects if soft tissue mobs on tibialis anterior or any other muscle when measured with pressure algometer.

Suppose a gas like hydrogen is stored in a tank of given volume at given temperature and pressure. If the tank has developed a leak of 1 mm diameter, how much time system will take to reach 50% of the original pressure? How to proceed to solve this problem

Suppose we have to inject CO2 within a deep geological formation, we have overburden and pore pressures given. How do we decide the maximum pressure which the formation can allow to rise without leading to formation failure?