HW_13 - kg/s from 90 C to 60 C by water (cp = 4.18 kJ/kg/K)...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Homework Assignment 13 1. At the Coal and Biomass Energy Lab, combustion air is preheated from ambient (25 ºC, 101.3 kPa) conditions by an electrical heater wrapped around a pipe. If the heater is rated at 8 kW and the combustion air needs to be heated to 200 ºC, a. what is the maximum mass flow rate of air that can be heated? b. using EES, investigate the effect of exit temperature on mass flow rate by varying the exit temperature from 50 ºC to 250 ºC in increments of 25 ºC. (Use variable specific heats) 2. Water at 60 ºF and 60 psia is heated in a chamber by mixing it with saturated water vapor at 60 psia. If both streams enter the mixing chamber at the same mass flow rate, determine the temperature and the quality of the exiting stream. 3. A heat exchanger is to cool ethylene glycol (cp = 2.56 kJ/kg/K) flowing at a rate of 2
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: kg/s from 90 C to 60 C by water (cp = 4.18 kJ/kg/K) that enters at 15 C and leaves at 80 C. Determine a. the rate of heat transfer b. the mass flow rate of water 4. A 6-L evacuated rigid bottle is surrounded by air at 150 kPa and 25 C. A valve at the top of the bottle is opened and air flows into the bottle. Eventually, equilibrium is established between the bottle and the ambient. Determine the amount of heat transfer that occurs during the filling process. Use variable specific heats. 5. Simplify the general forms of conservation of mass and conservation of energy to analyze inflating a balloon. List all assumptions. Due Monday July 12, 2010 10:00AM...
View Full Document

Ask a homework question - tutors are online