Mechanical Engineering Principles

252 MECHANICAL ENGINEERING PRINCIPLES Scale Float Tapered tube Direction of fluid flow Figure 22.10 be achieved using a Pitot-st ...

FLUID FLOW 253 Applications of electromagnetic flowmeters are found in the measurement of speeds of slurries, pastes and viscous ...

254 MECHANICAL ENGINEERING PRINCIPLES wherea 1 =cross-sectional area at section 1, a 2 =cross-sectional area at section 2, v 1 = ...

FLUID FLOW 255 (a) Free surface h (b) Vena contracta n 2 2 Figure 22.13 Leta=area of orifice. Due to the vena contracta the equi ...

256 MECHANICAL ENGINEERING PRINCIPLES tall buildings and trees, civil engineers normally assume that: Pressurep= 0. 5 ρv^2 This ...

FLUID FLOW 257 Write down the formula for the pressure due to a wind acting perpendicularly on a tall slender building. Exerci ...

23 Ideal gas laws 23.1 Introduction The relationships that exist between pressure, vol- ume and temperature in a gas are given i ...

IDEAL GAS LAWS 259 Hence,force on the piston =( 750 × 103 Pa)( 300 × 10 −^4 m^2 )= 22 .5kN Now try the following exercise Exerci ...

260 MECHANICAL ENGINEERING PRINCIPLES Hence V 1 423 = 2 3 V 1 T 2 from which,final temperature, T 2 =^23 ( 423 )=282 Kor( 282 − ...

IDEAL GAS LAWS 261 Initial pressurepR=200 kPa, and the pressure of gasesRandQtogether,p=pR+pQ=320 kPa. By Dalton’s law of partia ...

262 MECHANICAL ENGINEERING PRINCIPLES Problem 10. Some air at a temperature of 40 °C and pressure 4 bar occupies a volume of 0.0 ...

IDEAL GAS LAWS 263 A spherical vessel has a diameter of 2.0 m and contains hydrogen at a pres- sure of 300 kPa and a temperatur ...

264 MECHANICAL ENGINEERING PRINCIPLES 25 °C. Air is released from the cylinder until the pressure falls to 300 kPa and the tempe ...

IDEAL GAS LAWS 265 Now try the following exercise Exercise 124 Further questions on ideal gas laws A vesselP contains gas at a ...

266 MECHANICAL ENGINEERING PRINCIPLES A gas at a temperature of 27°C occupies a volume of 5 m^3. The volume of the same mass of ...

24 The measurement of temperature At the end of this chapter you should be able to: describe the construction, principle of ope ...

268 MECHANICAL ENGINEERING PRINCIPLES temperature. The position of the end of the column of liquid in the tube is a measure of t ...

THE MEASUREMENT OF TEMPERATURE 269 MetalA MetalB X Y I I Vx Vy G Figure 24.2 is usually called the ‘hot junction’ and the lower ...

270 MECHANICAL ENGINEERING PRINCIPLES (ii) can be made very small and compact, (iii) is robust, (iv) is easily replaced if damag ...

THE MEASUREMENT OF TEMPERATURE 271 Protective sheath (made of glass, quartz, porcelain or metal) Coil (of platinum, or nickel, o ...