Ask Question, Ask an Expert

+1-415-315-9853

info@mywordsolution.com

Ask Mechanical Engineering Expert

problem1.    Part A
A compressor installed at a wharf (for loading container ships) is able to give 6 bar.g pressures into the pressure receiver. The compressor is moved to a site that is 5000 ft above sea level (atmospheric pressure 0.85 bar.a) in the mountains. What is the revised discharge pressure (guage pressure) of the compressor?
Assume there is no change in temperature.

Part B

Is the assumption of change in temperature valid for calculating the discharge pressure of the compressor?

Part C

The temperature at the wharf is 35 oC and in the mountains is 19 oC, what is the reduction in volumetric output from compressor?

Questio2.

The system on site is a pressure sand filter, with a service curve. The filter is backwashed using the feed pump, at a higher flow rate, shown as backwash curve.

1162_centrifigual pump curve.jpg

Service duty point: 3 m3/h
Backwash duty point: 9 m3/h

Part A

What is the speed of the pump to achieve the service and backwash flow rates?

Part B

What would be the best way to control the speed of the pump? Why?

Part C

The pump is set up as a fixed speed constant pressure system (pump runs once system pressure reaches 550 kPa, turns off, when pressure drops to 450 kPa plant re-starts) to maintain a system pressure of 500 kPa at the discharge of the pump. What would be the service and backwash rates from the pump?

problem3.

A pump station has been designed to lift water out of a 6 metre deep pit (vented to atmosphere) via a centrifigual pump mounted at ground level.
   
    Liquid conditions     20 OC
    Suction pipe work losses    2.0 metres
    NPSH safety factor                 5.0 kPa
    Vapor pressure @ 20oC    0.25 metres

Part A 

find out the Net Positive Suction Head (NPSH) for the system?

Part B

In summer the liquid temperature rises to 60 oC, this changes the water vapor pressure to 2.05 metres. What is the revised NPSH for the higher water temperature?

Part C

Pressure loss in the suction pipe work is directly proportional to water veloicty in the pipe work squared, which is inversely proportional to suction pipe work diameter squared.

problem4.

We have a reciprocating compressor operating at 800 rpm.  Suction pressure and discharge pressure are held constant by other systems that have nothing to do with the compressor.  We increase the speed from 800 to 840 rpm (a 5% increase).

Part A
 What is the change in flow rate through the compressor Flow increases by (840/800) or 1.05, or 5% increase?

Part B
What is the change in pressure rise through the compressor?

Part C

What is the change in power that must be delivered to the compressor?

problem5.

We are operating a centrifugal compressor. The gas composition does not change during this excursion.  While holding suction pressure and flow rate constant, the inlet temperature rises.  What would you expect to happen to the discharge pressure, and why?

Mechanical Engineering, Engineering

  • Category:- Mechanical Engineering
  • Reference No.:- M9685

Have any Question? 


Related Questions in Mechanical Engineering

Problem -a piston at one end of a gas filled circular tube

Problem - A piston at one end of a gas filled circular tube of area S oscillates with real-valued velocity: U p (t) = U 1 cos(ω 1 t) + U 2 sin(ω 2 t) Note that two oscillation frequencies are present. The other end of th ...

1 if the density of sea water is approximated by the

1. If the density of sea water is approximated by the equation of stat is the compressibility, determine the pressure and density at a point 32,000 ft below the surface of the sea. Assume β = 300,00 psi. 2. The change in ...

Problem 1 -there is a circular combined open and closed

Problem 1 - There is a circular combined open and closed thin-walled section as shown in the figure. (R = 100mm, t = 2mm, S y = 100N) When shear force S y is applied to Web 24, calculate: a) Calculate I xx for the x-axis ...

The vibrational partition function for an unknown diatomic

The vibrational partition function for an unknown diatomic molecule at 300 K is 2.33. Find the maximum value of the vibrational constant ve in cm-1 such that at least 5% of the molecules in a 300 K sample will be found i ...

A 1 in times 10 in plank on a redwood deck has l 48 in

A 1 in × 10 in plank on a redwood deck has L = 48 in long and supported on three joists that rest on the ground and so do not bend. The joists act as pin/roller supports for the plank. If a 130 lb person stands on the pl ...

There is a typo in the problem related to combustion of

There is a typo in the problem related to combustion of hydrazine. The sentence alluded to products should read: "Because of the fuel choice, expected products of combustion are H2, N2 and H2O"In the version you received ...

For the bar in problem 1112 find the largest allowable

For the bar in Problem 11.12, find the largest allowable value of P if the allowable compressive stress is 250 MPa. Problem 11.12: A steel bar with the cross section shown and effective length L = 2.5 m is subjected to a ...

Invent a structure that can completely eliminate the narrow

Invent a structure that can completely eliminate the narrow gate effects. This is known as the fully recessed stepped oxide (FROSOX) whose sidewall oxide is thicker than the gate oxide and they are connected by a step or ...

The number of molecules crossing a unit area per unit time

The number of molecules crossing a unit area per unit time in one direction is given by where n is the number of molecules per unit volume and v is the average molecular velocity. As the average molecular velocity is app ...

1 a differential manometer is used to measure the pressure

1. A differential manometer is used to measure the pressure change caused by a flow constriction in a piping system as shown. Determine the pressure difference between points A and B in psi. Which section has the higher ...

  • 4,153,160 Questions Asked
  • 13,132 Experts
  • 2,558,936 Questions Answered

Ask Experts for help!!

Looking for Assignment Help?

Start excelling in your Courses, Get help with Assignment

Write us your full requirement for evaluation and you will receive response within 20 minutes turnaround time.

Ask Now Help with Problems, Get a Best Answer

Section onea in an atwood machine suppose two objects of

SECTION ONE (a) In an Atwood Machine, suppose two objects of unequal mass are hung vertically over a frictionless

Part 1you work in hr for a company that operates a factory

Part 1: You work in HR for a company that operates a factory manufacturing fiberglass. There are several hundred empl

Details on advanced accounting paperthis paper is intended

DETAILS ON ADVANCED ACCOUNTING PAPER This paper is intended for students to apply the theoretical knowledge around ac

Create a provider database and related reports and queries

Create a provider database and related reports and queries to capture contact information for potential PC component pro

Describe what you learned about the impact of economic

Describe what you learned about the impact of economic, social, and demographic trends affecting the US labor environmen