Pump Definition and 621 Threads

For those who don't know, I'm an HVAC engineer. From time to time, the issue of heat pump efficiency comes up. When picking a system, obviously efficiency (cost) is important, so we need to decide between, usually, heat pumps (air source) and gas for a small split system. The government has a...

Homework Statement Air conditioners operate on the same principle as refrigerators. Consider an air conditioner that has 7.00 kg of refrigerant flowing through its circuit each cycle. The refrigerant enters the evaporator coils in phase equilibrium, with 54.0 % of its mass as liquid and the...

What does it take to manufacture such a syringe pump? What kind of motor is usually used in these systems? http://www.macros.com.tw/p_kds.asp

Thermo --> Heat Pump, confirmation. Homework Statement A cooling unit for a fridge has a 100 W power input. Environment temperature is 298 K. The heat which enters the fridge due to defective isolation is 350 W. What is the minimal temperature the fridge can reach? Homework Equations...

pump add air into the flat tire in the gas station. The compressed air is at 180 psia and 60F(+460). the tire is initially at vaccum, therefore p0=0 psia. Air is added into the tire until it reaches Pf =32.9 psig which is (23.9+14.7=47.6 psia), then stopped . this process is adiobatic which...

Tank Problem -- Pump at the END? I will try to post more relevant data if possible but my main issue is this: I have a pump that receives water from a reservoir--so basically a gravity feed into an open-air tank. The tank itself is supposed to feed into a pump (that is located at the very...

A bicycle pump contains air at STP. As the tire is pumped up, the volume of air decreases by 30% with each stroke. What is the new pressure of air (in atm) in the chamber after the first stroke, assuming no temperature change? Select the correct answer. a. 1.4 b. 0.7 c. 2.6 d. 0.9 e. 2 What...

I am having problems with a pump installed. I am trying to determine if it is to large for the application because there is a lot of cavitation during the process. I have the pump information 60GPM with a 5Hp Motor. RPM is 1725. How can i calculate lbs/hr of the fluid flowing?

hi guys. I need some basic information about a pump that will be able to transport a nickel slurry up around 1-2m high. the mass flow rate of the slurry is 27 kg/s with a density of 1218 kg/m^3. the temperature of the slurry is 25 deg c. What is the best type of pump to use in this...

When I select a water pump for a pipe, I select the pump that matches the pipes nominell diameter. A DN100 pump for a DN100 pipe for instance. It only seems natural to me. But I see that others usually go down on the pump size, a DN65 or DN80 pump for a DN100 pipe for instance. Why is this...

Homework Statement on a venturi pump the fluid, air or water move through a narrow tube and increases speed and also decreases pressure. Now I have read before that the dynamic pressure and the static pressure are added to get the total pressure. How fast does the fluid have to flow to create...

could anyone please tell me how a manual/hand water pump works? thanks

Fluid - Determining pump power for pipeline with constant head gentlemen, i need some help to solve for part b as attached. The friction factor for pipe 1 & 2are 0.003106 and 0.003438 respectively and the Z value calculated is 9.997m of water. With a 20% increase in flow rate for the piping...

Hi, I'm currently an art student at the University of Houston, and I've run into a bit of a roadblock. I'm working on an installation in which an audio signal from a headphone jack will be sent to an A/V Receiver Unit. From the A/V unit, the wiring for the left speaker will be hooked up to...

1. A heat pump is being used to keep the temperature inside a house at 23 C, while the tmeperature ouside is -6.0 C. The heat pump is providing heat inot the house at the rate of 8.8 kW with a coefficient of performance of 5.6. A) What power input (in KW) is needed to run the heat pump? B)...

Homework Statement A hemi-spherical tank with a 5 foot radius is full of water. Given than water weighs 62.5 pounds per cubic foot, find the work required to pump the water out of the tank Homework Equations Radius = 5 so range will be 0 to 5. Formula should be pi * r^2 for each...

Hi, Is it more efficient to run a heat pump in a house 24/7 or turn it off at night time and during work. All the pros seem to say its more efficient running them 24/7 I can't understand that as there is more heat loss with the greater heat differential running it 24/7 Thanks Darren

About those hydraulic devices that are used for lifting cars and such; how can you calculate the maximum speed at which those will operate?

hay everyone i have a research on centrifugal pump and specifically on the pump volute. this research is for fundamentals of manufacturing course, i need some help with finding the appropriate sources of information. so does anyone know a good book or a website that is not in...

Homework Statement A pump is required to lift 800 kg. ( about 200 gallons) of water per minute from a well that is 14.0 m deep and eject it with a speed of 30 m/s a.) how much work is done per minute in lifting the water? b.) how much in giving it kinetic energy? Homework Equations W =...

improve photosynthesis energy capture efficiency

what would be a good setup to shoot as much water as possible , as far as possible?

Homework Statement When you look at the manual hand pump, you would push down on a lever and a piston would rise creating a vacuum in the chamber. which would bring the water upward because of atmospheric pressure push the water upward. Now I have two questions about this. My first question...

Hi. I'm a high schooler from Oregon, and I'm in a bit of a dilemma right now. What I'm trying to do is make a 5x5-pin tactile display for a high school physics project. I currently have a Makezine controller that can sink 1A @ 12VDC per analog output, and control 2 stepper motors or 8 servos...

Homework Statement Water is pumped steadily out of a flooded basement at a speed of 5.5 m/s through a uniform hose of radius 1.2 cm. The hose passes out through a window 2.9 m above the waterline. What is the power of the pump? Homework Equations R_v=Av R_m=\rho Av where P is...

Homework Statement It is proposed to heat a house using a heat pump operating between the house (27 degees) and the outside (-13 degrees). The heat loss from the house is 7kW. What is the minimum power required to operate the heat pump?Homework Equations The Attempt at a Solution e=Th/(Th-Tc)...

Air conditioners operate on the same principle as refrigerators. Consider an air conditioner that has 7.00 kg of refrigerant flowing through its circuit each cycle. The refrigerant enters the evaporator coils in phase equilibrium, with 54.0% of its mass as liquid and the rest as vapor. It flows...

I have found a few sites that contains plans for a hydraulic engine that could run itself for a total of nine days. http://www.rexresearch.com/clemengn/clemengn.htm" http://www.keelynet.com/energy/clemindex.htm" Would it be practical to use this as an engine.

hello every one :smile: i don't know if this is really the correct place for posting this question but here it goes!:wink: Can somebody tell me how the venturi metre and the filter pump work? thanx in advance! :blushing:

Hello people, I have a question regarding operation of a water pump. Say, I have a large hot water pump (for purpose of heating) and that pump "pushes" (don't know correct term) water into system. Thers is one big pipeline consist of two pipes (one for sending and one for receiving water). I...

1. North vs. South. A heat pump is designed for southern climates extracts heat from the outside air, and delivers air at 20C to the inside of the houses. What is the average coefficent of performance of the heat pump: (Consider this to be a Carnot device) a) In the south where the average...

Hi all! How do we define the power of a pump? I read a formula from a book which defines the power of the pump as follows: Power of the pump = Maximum back pressure * maximum flow rate / 2 Can anyone explain why the right hand side equals the left hand side? I don't understand why the...

Hello, I cannot figure out which pump or size of pump would fit the need I have. Can you please review the need and recommend a type and pump model/specification that you think would work for this application? I need to have a fluid flow of these specs, I don't have any constraints or...

While in California – the land of air conditioners and swimming pools – I noticed a relatively easy freebee for air conditioners and heat pumps. First. for comparison and perspective, consider that geothermal transfer systems are now used to replace the condenser/evaporator coil in...

Hello All, I am building an ROV and would like to use bilge pumps for the thrusters. I would like to calculate the thrust that a prospective pump is going to create so as to decide which pump to buy. I know that the pump can output 1250 gallons per hour and has a nozzle with a 2" diameter...

Hi guys, could someone help me on this? I'm stuck :( *A motor draws 35kW electricity, it operates at 90% efficiency. The motor is connected to an oil pump which has an inlet diameter of 8cm & an outlet diameter of 12cm. pressure rise in the oil pump is 400kPa. oil enters the pump at 0.1m^3/s...

I have a glue pump system need to operate it by an electrical motor , so don't know how to choose the coupling designation ... may be there are some designation tables or other websites helping for that thing . also if there are some EQUATIONS , about that to depend on . with my best wishes

My textbook shows a PV diagram for a steam engine with the pump stage having no change in volume and with only a vertical increase in pressure. How can that be done. I can only imagine pumping a substance by pushing it inwards hence increasing its pressure but also reducing its volume. How can...

Senator Biden suggested this on Meet The Press today: Mandate that every station must have a flex-fuel pump. This sounds like a very tempting idea. Whether the best approach or not, I think we need to set national goals to convert the US to alternative fuels as the standard within ten years...

Please move to appropriate forum if necessary. I need some help. Attached is a pic of my standard 1/4hp Hayward pool pump. I want to enclose it to make it quieter. (The sound is being transmitted by air rather than by physical contact.) As a "proof of concept" I stuffed it in a storage bin...

A water intake at a pump storage reservoir (Fig. 14-44) has a cross-sectional area of 0.87 m2. The water flows in at a speed of 0.35 m/s. At the generator building, at distance D = 180 m below the intake point, the cross-sectional area is smaller than at the intake and the water flows out at 9.8...

Consider a water pump that receives liquid water at 15C and 100kPa, and delevers it to a same diameter short pipe having a nozzle with exit diameter of .01m to the atmosphere at 100 kPa. Neglect KE in pipes and assume constant internal energy u for water. Find exit velocity and mass flow rate if...

In a home heat pump, heat is absorbed from the Earth by a fluid circulating in buried pipes and delivered to the home interior. Suppose that the heat pump is 40% as efficient as a Carnot refrigerator. If the ground surrounding the pipes is at 5`C and the interior temperature of the house is kept...

-------------------------------------------------------------------------------- A pump is to lift 29.0 kg of water per minute through a height of 3.70 m. What output rating (watts) should the pump motor have? An airplane pilot fell 380 m after jumping without his parachute opening. He...

"Pump down" principle A building has a storage room that needs to be cooled. This cooling-system is to be controlled using the "pump-down" principle. I have absolutely no idea what this implies! Anyone...?

A heat pump has a coefficient of performance of 7.05. If the heat pump absorbs 20 cal of heat from the cold outdoors in each cycle, find the heat expelled to the warm indoors. Answer in units of cal. I believe COP (heating mode) : 7.05 and COP = Qh/W Qc = 20 cal so I have to find Qh= ? cal...

A piston pump having a barrel of effective volume 100cm3 is used to exhaust a vessel of volume 2.5x(10^3)cm3. If the initial pressure in the vessel is 1 atm, estimate the reduction in pressure produced by two strokes of the pump, assuming that all processes are isothermal and that air behaves as...

Is the overall flow rate through a closed loop with a pump constant? I've always though that if a pump can do a specific amount of work, it doesn't matter if the 'loop' of tubing goes up and down, or what types of turns it takes. I've thought this because if the tubing goes down then up (or...

I'm having real trouble understanding the working process of a heat pump. A liquid with a certain temp flows in a system and gets vaporized, then it is compressed so that pressure and temp increase. Then it is cooled by a substance with lower temp so that it becomes a liquid again, and this...

I have been working on this problem for 2 days and can't seem to figure it out.. A 1500hp pump throws a jet of water 125 m into the air. (a) With what speed does the water leave the mouth of the fountain. (b) If the overall efficiency is 60%, how many liters of water per minute are thrown...