HW_24_Soln

# HW_24_Soln - ME 309 Fall 2008 Section 2(Merkle Homework 24...

This preview shows pages 1–2. Sign up to view the full content.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: ME 309 Fall 2008 Section 2 (Merkle) Homework # 24 Due Mon 27 Oct 2008 Problem 24-1 . Water at 300 K flows from a higher reservoir to a lower one through a 10- mm diameter cast iron pipe that is 50 m in length. The average velocity is measured to be 10 m/ s. The entrance to the pipe is a square-edged entrance. The exit is a sudden expansion. Estimate the height of the free surface of the upper reservoir. Take α = 1 throughout. Solution: Given: density, viscosity, pipe diameter, pipe length, pipe type, and entrance and exit characteristics; Assumptions: incompressible flow, mechanical energy equation holds, alpha = 1. Find : Flow rate Analysis: Apply mechanical energy equation: pump m l h h h gz U p gz U p Δ- + = + +- + + ∑ ∑ 2 2 2 2 2 1 2 1 1 1 2 2 α ρ α ρ No pumping, last term drops out. Density: 998 kg/m 3 μ = 0.001 N.s/m 2 Cast iron pipe, ε = 0.26 mm Table 8.1, p330. Minor losses: Square-edged entrance K ent = 0.5 (Table 8.2, p334, or from AR= 0 on Fig. 8.15) Sudden exit (area ratio 0 from Fig. 8.15) a K exit = 1.0 Apply mechanical energy equation from free surface in upper reservoir to pipe inlet: (Note: It’s okay to apply mechanical energy equation from surface to surface at the outset—I’ve done it in increments to be sure things are clear.) (No losses in this region; velocity at surface is zero: 2 1 2 1...
View Full Document

{[ snackBarMessage ]}

### Page1 / 6

HW_24_Soln - ME 309 Fall 2008 Section 2(Merkle Homework 24...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online