Pump Definition and 655 Threads

  1. M

    Fluid mechanics & pump sizing (pseudo parallel pumps)

    Three wells each pump 20 gpm to a combined header. What is the correct way to size pumps 1, 2, and 3 (with respect to head, flow) considering this configuration shown in sketch?
  2. Dassie

    Grid tied micro hydro using Pump As Turbine

    Hello everyone, We’ve successfully managed to beat load shedding (ie. planned power outages) during the summer months on our farm in South Africa. Our setup includes: 8 Deye hybrid 12 kW 3-phase inverters 48 Shoto SDC-10 Box 5 batteries 1 x 10 kW and 2 x 20 kW grid-tie inverters feeding...
  3. G

    Characteristic system curve for a two branch system

    How can one find the characteristic system curve for a system with two different branches, each with its own fluid, T and centrifugal pump, that will than converge in a single line making a whole new fluid at a new T ? Thanks in advance.
  4. N

    Effect of pressure due to change in diameter of pipe

    The pump has an outlet size of 4 inch 1) In case 1, 4 inch pipe is connected at length of 20 m 2) In case 2, 2 inch pipe is connected using reducer In both cases the pump outlet conditions are same( having same flow rate at a given pressure) What happens to pressure at the end of the pipe in...
  5. N

    How to maintain flowrate and pressure head in a pump?

    Pump is supply fluid to the 35 nozzles through 3 inch pipe and manifold.At nozzle the pressure is 32 m and pressure at pump outlet is 30 m .The flow rate required at nozzles is 500 lpm. Pump can deliver 860 lpm at 24 m head.pump size 100x100 mm 1)how delivary pipe size affects the pressure head...
  6. LEO31

    System curve and centrifugal pump suitability

    I’m trying to calculate the system curve of an already existing plant, the complexity lies in having 2 different lines, each with its respective pump 1- A substance contained in a closed tank with a liquid level of 40 ft connected to pump 1. 2- a closed tank of pure water connected to pump 2...
  7. R

    Can you help me understand this modification to a formula?

    Hello guys, I did a efficiency analysis with two different propellers. For that I build up an experiment to make measurements. The experiment is build up like this: You can see a prop inside the tube which after turning on will pump water from one side to the other. After a certain duration...
  8. M

    Can Mechanical Engineers Revolutionize the Pump Industry?

    Mechanical engineer working in pump industry
  9. R

    Does a pump face less back pressure if a vertical pipe is wider?

    How did you find PF?: google search I've worked at sea for a number of years and now I'm particularly interested in learning more about fluid dynamics in order to find practical solutions to environmental problems. I would be very grateful for any advice people on this forum can give me. At...
  10. S

    Interesting concept -- pump, motor or both?

    Not sure if it is meant to be a pump or a compressed air motor. Or maybe it can work as a pump or as a motor? What would be the practical problems? Does it add anything to the prior art? --- Edit : Not sure how it will make a proper seal, with that step in the back plate.
  11. nicolas1409

    B Question about a vacuum ejector (vacuum pump using the Venturi effect)

    I have a vacuum ejector and with a suction cup that drops items. think maybe it could be a pressure drop. but what happens if a vacuum ejector gets less pressure, does it suck less? know it's something with bernoulis
  12. C

    I In a closed loop system with a pump, how can we control the pressure?

    How can we control the pressure of the water inside a closed loop system (chiller system for example)? Let´s say, we have a pump curve and an system resistance curve that can be modified (through opening or closing some valves) In everywhere, what I see is that the intersection of the system...
  13. H

    Why am I blowing a laptop powerpack with dc water pump?

    Hi, I have a water pump rated 12v dc 2.3A. I tried using Microsoft Surface powerpack rated at 15v dc 2.5A to power it. Pump just started pulsing. I removed the water pump and checked the voltage coming out the powerpack and it was fluctuating between 0 and 15v. Thought I had a dud powerpack so...
  14. C

    Determine pump spec necessary to overcome leak

    A vacuum pump is mounted at ground level. The pump is connected to a tree of overhead pipework at a height of 20ft, connected to the pipework are 12 hose reels that can be attached to oil drain tanks. The client requests that the pump be sized so that sufficient vacuum can be achieved to suck...
  15. M

    How to find velocity of gas pump flowing into car tank

    The general balance equation is as follow: d[m{u+gz+v2/2)sys=(u+gz+v2/2)dmin-(u+gz+v2/2)dmout +dq+dw. I understand that I would take in consideration the cross sectional area as well as the mass flow rate. However I can't figure out what else to consider as if atm pressure should be considered...
  16. Al-Layth

    Mechanism Ideas for: Rotary Action-input Pump?

    I'm trying to come up with a design for a handheld pump that will be used to suck diesel from a car's fuel tank. There's definitely going to be a pipe dipping into the fuel tank, and there's definitely going to be a human manually operating the pump. I'm trying to think of a mechanism that...
  17. K

    Using compressed air through a venturi pump to suck oil?

    Hello, was wondering if I could pass compressed air through a venturi pump to pull floating oil from a tank? If yes, how do I control the eventual mixing of oil with the air from the outlet end? The requirement is given to me by one of my clients who wants an easy, and low-cost solution to...
  18. hxtasy

    Gerotor pump, will it work in a closed system without air?

    just hypothetical question, First off I am not very knowledgeable in pumps. Let's say you have a pump to pump fluid, i don't think the type matters, self priming as I understand it creates a vacuum with the air in the system to pull the fluid towards the gear pumps. I'm wondering what happens...
  19. S

    Does a "heat pump" not spew HFCs like an "air conditioner"?

    https://slate.com/technology/2022/07/inflation-reduction-act-climate-bill-manchin-heat-pump-solar-panels-electric-cars.html First, this text makes no sense as it seems to say that the problem with A/C can be solved by "shift[ing] hot air in". But then it also seems to say that a "heat pump" -...
  20. S

    I Maximizing Efficiency: Exploring the Possibility of Self-Running Heat Pumps

    So heat pumps are an interesting thing which I've recently discovered, and it has led to curiosity about how they work and what you can do with them. I hope to make my own property at some point, so a heat pump will doubtless come up then as I would like it to be an eco-home. Ground source heat...
  21. D

    I Experimenting with a vacuum pump

    Hello, I would like to carry out a few experiments with a vacuum pump under a vacuum bell jar. However, I have no experience with this and the operating instructions could only help me to a limited extent. Specifically, I am interested in the sequence for switching off the pump: When I have...
  22. link223

    Forces acting on a Walking Beam (oil rig pump) from a pivot pin

    So.. question: - How do I know that only the pin is at work at E and not those 2 beams? my guess: It is because those 2 beams are connected to the pin whilst the pin is the one that exerts a force on that walking beam DEF?
  23. Ben_the_Druid

    I Vacuum pump operating at high altitude

    Hi I live in a high Altitude around 2500 meter over sealevel. I have a vacuum pump, at max my vacuum meter shows 21 inHG inside the vacuum chamber . my vacuum pump(welch 2014B) has a max of 40 torr it say the technical datasheet. What is now my endpressure in torr in my vacuumchamber?It's...
  24. H

    MATLAB Modelling a Heat Pump with Linear Compressor using MATLAB Simulink

    Hello, I am a final year mechanical engineering student designing a heat pump with a linear compressor for an electric vehicle and have decided to model this using Simulink, I would love some help on the governing equations/formulas needed for each component of the heat pump as well as guidance...
  25. lonewolfx

    Engineering Pump work required to reach a maximum reservoir height

    The following image represents the system under analysis: Using a reference point 1 on the surface of the lower reservoir, point 2 at the discharge of the middle reservoir, and point 3 at the discharge of the upper reservoir, and assuming the pressure is equal to atmospheric pressure at all of...
  26. M

    Rotary Vane Vacuum Pump Question

    So in the image below from a video I watched , the narrator states “gas pressure from the refrigerator rushes into the low-pressure chamber “ So, I do understand that gas will push its way into a low-pressure area from a high-pressure (high to low)….but what I am unclear of is to how that...
  27. R

    How does a pump trade head for flow rate?

    A pump’s power is a product of its pressure rise times volume flow rate. Commonly, a pump is specified by giving the pressure rise, or head, it can provide and the flow rate, such as in gallons per minute(GPM). But some pumps provide the user with a chart that shows how the pressure rise can...
  28. D

    B Lorenz COP of a heat pump and the temperatures of the hot/cold reservoirs

    @Dale : “The COP of a heat pump and the efficiency of a heat engine both depend strongly on the temperatures of the hot and cold reservoirs. For this calculation you need to go back and check the sources for the temperatures corresponding to each of these numbers. You will find that the Stirling...
  29. D

    B Can a Heat Pump and Stirling Engine Create a Perpetual Energy Cycle?

    I was reading about heat pumps and it made me wonder… would the following process be physically possible…? I attach the hot side of the heat pump to the hot side of the stirling engine. 400% COP (coefficient of performance) means 1 kilowatt hour of electricity consumed by the heat pump delivers...
  30. C

    Wiring 3/4 HP Submersible Well Pump - Is #10 OK?

    3/4 hp submersible well pump with #12 wire at top of casing from pump. I had a senior moment and wired from the panel to the pressure switch and switch to top of casing with #10. I am thinking I am ok as long as the breaker never exceeds 20 amps. Just want to make sure. Thanks.
  31. K

    Can you move water vertically without a pump?

    Hi I would like to design a water fountain/waterfall and want to know if i can pump water upward without using a pump. Perhaps using gravity and pressure. My planned size would be between 1 foot to 10 feet.Thanks
  32. M

    Question about Refrigerants used within a Heat Pump

    I've been given the following 2 questions (please see below), and I've been asked to come with answers and arguments for my decision for the proposed answer, since there is just 1 correct answer per question. (so you can see my attempt below) Q1)The refrigerants have to: a)Vapourise at high...
  33. JamesBennettBeta

    Machine Dynamics: Manual Air Pump Calculation (please check my answer)

    mentor note: moved from ME forum hence no HW template. Summary:: I am stuck into this problem for almost a week now. I think I solved it, but it seems something is wrong. Can someone point me, what is wrong here. It'll be so much helpful. I am stuck into this problem for almost a week now. I...
  34. DaveC426913

    Looking for a (bilge) pump to suit my needs

    Looking for an electric pump for my bilge. I'm having some trouble finding a smallish pump that won't foul with debris.- 12v ideally - no reason for a float, I'll operate it with a switch - must input by hose, not mesh/grill - must be able to run dry and self-prime - fittings must be large -...
  35. M

    Maximum number of microchannels in parallel for a syringe pump

    Basically, I want to determine how many microchannels I can have in parallel to drive a fluid (for now assume water),without the syringe pump stalling. Let's say a syringe pump have a maximum linear force of 50 lbf. and I want to drive the fluid at 60 ml/hr. So if I have 4 parallel channels...
  36. M

    Heat pump efficiency calculations - Compressor power issue

    The heat pump comprises of the 4 components: evaporator, compressor, condenser and expansion valve. Thermal power required to heat the building: 12.1 kW at condensing temperature tc = 44.3 deg C For the evaporator: vaporizing temperature tv = -7 deg C Subcooling temperature for the heat pump Δ...
  37. russ_watters

    What factors affect heat rejection in vacuum pump systems?

    I'm working on a project to replace a couple of vacuum pump skids for a lab campus. The existing pumps are water-cooled, liquid-ring pumps. Since they are water cooled, there is effectively no heat rejection into the mechanical room(s) except through un-insulated exhaust pipes. The new pumps...
  38. A

    Selecting hydraulic motors and a pump for hydrostatic transmission

    So I'm trying to make a GoKart that utilizes a hydraulic drive for the front two wheels and a mechanical driveshaft for the back two wheels but my main questions are selecting the motors and pumps. I just want to clarify a few things since I'm not sure if I did my math right. The max RPM for...
  39. S

    Will a vortex form if you pump water up via the bathtub drain?

    ... And if it won't form spontaneously with reversed flow, then will a vortex at least sustain itself once we nudge it in one direction?
  40. T

    Positive displacement pump for spray nozzles

    Hi all, I have a positive displacement (diaphragm) pump that I am looking to use to supply spray nozzles. The pump has a max pressure rating of 69 bar at 30.6 L/min (1450 rpm). I however want my nozzles to spray at 15 bar pressure and from the nozzle performance data sheet that equates to 0.68...
  41. S

    Centrifugal pump behavior when the outlet is closed

    What would happen if the water pump output or outlet is closed and pump continues running. Will the rotor or impeller inside just rotate and rotate slowly just raising temperature of stuck water in the impeller or would there be sudden increase in pressure immediately damaging the seal. This is...
  42. StefanBoon

    Is it possible to have water levels at different heights without a pump?

    I wonder if air can remain trapped under a structure that has a deep and a shallow tube. I have already tested with a prototype whether increasing volume in the shallower tube works. Air bubbles came out on the short side, so this doesn't work. Is there any way to realize this concept.
  43. M

    External Gear Pump: Capacity & Pressure Effects

    Hi everyone, Let's say I have an external gear pump driven by the camshaft of a marine diesel engine. The nominal speed of the engine is 1800 rpm and the capacity of the pump at nominal speed is 8 L/min. Diesel fuel is supplied to the gear pump suction at 0.4 bar g pressure via a 15 mm pipe...
  44. A

    Pipe Design to pump sea water from the ocean to a boiler via intermediate tanks

    I am in the process of designing a pumping/piping system for fun, have no experience in this field, but I enjoy learning. I have been using ANSI/ASME codes in the project quite a bit. For the system I am using 4" nom. Schedule 40 316 SS pipe. The reason I selected the pipe is because the...
  45. rufusbufus

    Calculating the energy created by a bike pump that feeds a turbine

    Summary:: I have an assignment that is looking at how a bicycle pump is used to push air through a turbine to generate energy. I need to determine the energy input and energy created. I'm hoping I can get some direction on where to start. The concept is straightforward. A bicycle pump of...
  46. S

    Peak Amps of a heat pump based AC vs compressor based AC?

    In my city (USA) typical older houses have "100 Amp service" so their peak electric usage is limited to 100 Amps. In considering what sort of electric air conditioning system to install in such a house, peak usage is major consideration. Generally speaking, which type of residential unit...
  47. C

    Solve Heat Pump COP Equation with Q & T

    I have tried to solve this with these equations: COP=T(H)/( T(H)-T(L) ) and COP = Q(H)/ ( Q(H)-Q(L) ) But since I need both Q and T in the same equation, I can't find anything to solve it.
  48. S

    Selecting the Right Water Pump: Considerations & Reference

    If I was required to select a water pump for either domestic use or industrial, what are the consideration that I should take care of while choosing? How can I select a suitable pump according to height? What power should be implemented? Anyway, a general question would be "What is a reference...
  49. A

    How to calculate (pump) power to maintain a static head?

    i've this question that i can't seem to work out an answer. supposing that a (centrifuge) pump transfer an amount of energy (power) p to a column of water height h so that it maintains that as a static head. i.e. the water level in that tube is at a fixed height h due to the power transferred...
Back
Top