Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations waross on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Search results for query: *

  • Users: freefallingbody
  • Order by date
  1. freefallingbody

    Inlet vs. Outlet Damper

    Macmet, Outlet damper would increase static pressure at discharge, as you have pointed out. The system curve would move towards y-axis when you close the discharge damper. Regards Dinesh
  2. freefallingbody

    Inlet vs. Outlet Damper

    I Think there are two issues while comparing inlet and outlet dampers. The most important point is that an inlet damper changes the fan curve. Closing inlet damper brings the fan head-flow curve down, with the shut off head more or less unchanged. Along with this shift, the surge line also gets...
  3. freefallingbody

    COP air cooled evaporator vs. water cooled (incl. CT)

    A comparison of two types of systems are given below. These are DX units. Not chilled water systems. Type DX chiller DX chiller (air cooled cond.)(water cooled Cond.) Capacity, TR 100 100 Saturated Suction temp, C...
  4. freefallingbody

    Evaporative Condenser with HVAC CHiller ?

    Kiranne, There is still a lot of money being made from inefficiency, thats why. Evaporative condenser pads ( Celdek pads made by Munters) are common these days as an add on feature offered by manufacturers in coutries like India. Most of the Ice plants, cold storages etc use Ammonia chillers...
  5. freefallingbody

    VFD pressure control

    For an IC engine test bed, where the number of engines to be tested varied from 10 to 30, a control system as desired by infomechatronic was considered. That is, a variable freqnecy drive controling speed of the motor and solenoid valves on the water line to each engine. A pressure transmitter...
  6. freefallingbody

    GAS ENGINE DRIVEN INDUCTION GENERATOR

    I understand the reason for induction generator not popular, as it is not really a standby. I was only wondering when so many wind turbines are operating in India with induction generators, use of engine driven induction generators in demand saving may work out cheaper than engine-alternator...
  7. freefallingbody

    GAS ENGINE DRIVEN INDUCTION GENERATOR

    Waross, Gas engine generators at 3.5 kWh/Sm3 of natural gas and with gas price of Rs 10/Sm3, one can generate electricity at Rs 2.9 per kWh. In India, the typical utility rates are Rs 4.0 /kWh. Hence, actually, it is cheaper to run gas engine. No so with liquid fuels. Do you forsee any other...
  8. freefallingbody

    Refrigerant Air Dryers, condensate traps or what?

    Zsadiq, Compressed air need drying to avoid condensation at distribution systems and the points of use. Condensate which is formed when compressed air is stored in a receiver can be removed by using a condensate trap. But that is not sufficient. When air is compressed, it has a capacity to...
  9. freefallingbody

    GAS ENGINE DRIVEN INDUCTION GENERATOR

    SCOTTYUK, The system here is not to be used as a standby generator, it is needed to top up the demand. The state electricity utility charges very high for exceeding the contracted demand and hence need for captive generation when a large load like an annealing furnace comes into operation...
  10. freefallingbody

    GAS ENGINE DRIVEN INDUCTION GENERATOR

    Hi, For captive power plants, a typical system consist of engine and alternator. I wonder if I can use an Induction generator coupled to the engine with proper giverning systems to deliver the electrical power, instead of using the alternator. I hope this will not have the usual headaches of...
  11. freefallingbody

    Waste Heat Refrigeration

    macmet, I have two gas engine driven power plant of 1.4 MW each generating 4.0 TPH of 8.0 bar steam and 300 TR of chilling from engine jacket cooling water at 80 deg.C. This system can be called a trigeneration system as it generates electricity, steam and cooling. Absorption chiller can...
  12. freefallingbody

    selection of 2 pumps working in paralel pipe

    Waross, I have seen a system similar to that you have described, except the fact that it was intentional heating of water by keeping the pump at shut off. This was a vapour absorption chiller test bed of a manufacturer. The artificial heat load for chiller was provided by the churning of water...
  13. freefallingbody

    selection of 2 pumps working in paralel pipe

    Pablo2410, Your system is a friction head predominant system, static head in a closed loop system can be assumed to be zero. From the description, I understand that the resistance offered by the system to a flow of 960 gpm is 53.5 ftWC. If both pumps are going to be operated together, each...
  14. freefallingbody

    selection of 2 pumps working in paralel pipe

    Pablo2410, As GMCD mentioned, the flow delivered by the pump is highly system specific. If one pump alone operates to deliver 100 gpm actual flow ( not the name plate flow), adding another pump in parallel in a high static head system ( such as an over head storage tank) the flow may be 20 to...
  15. freefallingbody

    Centifugal Pump Flowrate

    Carf, I also faced similar problems related to guessing pump flow. The pump curves are useful for giving you within +/-30% if pumps are new. For that, you have to measure differential head across the pump under operation and find out the corresponding flow. If pump is old, I will also measure...
  16. freefallingbody

    Power factor correction

    Waross, Thanks for ur suggestions. Thats what I am going to do. Keep the capacitors needed for magnetising kVARs ON. Switching off all capacitors at no load ( what my client practiced till now) may not be a good idea. In the auto p.f controller, the sensing point now is at the secondary of one...
  17. freefallingbody

    Under-Voltage Motor Operation

    Beggar, If I may summarise the effect of 10% less voltage on motor parameters, Torque, starting & maximum running Decrease 19% Speed: Synchronous No change Speed: Full Load Decrease 1.5% % slip Increase 23%...
  18. freefallingbody

    Power factor correction

    Waross, You have understood my requirement. Now, the capacitors connected to the underloaded transformers are kept off manually when the load is less. And when I measured reactive power requirement at the LT side loads on all the transformers, it has shown positive. ( my meter will show...
  19. freefallingbody

    Power factor correction

    Hi, This is a question related to improving power factor. I have a 22 kV supply from the electricity supply utility grid and five transformers ( 2 x 1000 kVA, 3 x 500 kVA) step teh voltage down to 433 Volts. The utility billing is based on a meter connected at the 22 kV line. The five...
  20. freefallingbody

    Energy in compressed air

    Hi, I will rephrase my query: Consider the following sentences. 1. Compressed air is very expensive utility 2. Lot of heat is rejected in the process of compression First sentence is true. But, is the second sentence the correct reason for that? If the compression is completed in the...

Part and Inventory Search