Fundamentals of Heat and Mass Transfer
7th Edition
ISBN: 9780470917855
Author: Bergman, Theodore L./
Publisher: John Wiley & Sons Inc
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Chapter 9, Problem 9.98P
(a)
To determine
The heat loss across collector cavity.
(b)
To determine
The effect of plate spacing on the heat loss.
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QUESTION 6
A simple solar collector in Figure Q1 is built by placing a 5 cm diameter clear plastic tube around a
garden hose whose outer diameter is 1.6 cm. The hose is painted black to maximize solar absorption,
and some plastic rings are used to keep the spacing between the hose and the clear plastic cover
constant. During a clear day, the temperature of the hose is measured to be 65 °C, while the ambient
air temperature is 26 °C. Determine the clear plastic tube temperature and the rate of heat loss from the
water in the hose per meter of its length by natural convection.
Solar
radiation
||| 26°C
Clear plastic tube
Water
Spacer
Garden hose
65°C
Figure Q1
Heat transfer problem.The internal surface area is an enclosure is 50 meter square. The surface is black and maintained at constant temperature. A small opening in the enclosure has area 0.05 meter square. The radiant power emitted from the opening is 52W. (A) what’s the temperature of the interior enclosure wall. (B)if the interior surface is maintained in this temperature, but polished so that emissivity is 0.15, what will be the radiant power emitted in the opening.
PROBLEM 4:
A black thermocouple is inside a chamber with black walls. If the air around the thermocouple is at 20°C,
the walls are at 100-C, and the heat transfer coefficient between the thermocouple and the air is 75 W/m²K,
what temperature will the thermocouple read?
Chapter 9 Solutions
Fundamentals of Heat and Mass Transfer
Ch. 9 - The one-dimensional plane wall of Figure 3.1 is of...Ch. 9 - Using the values of density for water in Table...Ch. 9 - Consider an object of Characteristic length 0.01 m...Ch. 9 - To assess the efficacy of different liquids for...Ch. 9 - In many cases, we are concerned with free...Ch. 9 - The heat transfer rate due to free convection from...Ch. 9 - Consider a large vertical plate with a uniform...Ch. 9 - For laminar free convection flow on a vertical...Ch. 9 - Consider an array of vertical rectangular tins,...Ch. 9 - A number of thin plates are to be cooled by...
Ch. 9 - Prob. 9.11PCh. 9 - Prob. 9.13PCh. 9 - The plate described in Problem 9.14 has been used...Ch. 9 - Determine the average convection heat transfer...Ch. 9 - Consider a vertical plate of dimension 0.025m0.50m...Ch. 9 - During a winter day, the window of a patio door...Ch. 9 - Prob. 9.20PCh. 9 - A household oven door of 0.5-m height and 0.7-m...Ch. 9 - Consider a vertical, single-pane window of...Ch. 9 - Consider laminar flow about a vertical isothermal...Ch. 9 - Consider the conveyor system described in Problem...Ch. 9 - Prob. 9.25PCh. 9 - Consider an experiment to investigate the...Ch. 9 - The vertical rear window of an automobile is of...Ch. 9 - Prob. 9.28PCh. 9 - Prob. 9.29PCh. 9 - Prob. 9.30PCh. 9 - A refrigerator door has a height and width of...Ch. 9 - In the central receiver concept of a solar power...Ch. 9 - Prob. 9.34PCh. 9 - Airflow through a long, 0.2-m-square air...Ch. 9 - Prob. 9.36PCh. 9 - An electrical heater in the form of a horizontal...Ch. 9 - Consider a horizontal 6-mm-thick, 100-mm-long...Ch. 9 - Prob. 9.39PCh. 9 - Prob. 9.40PCh. 9 - Prob. 9.41PCh. 9 - Many laptop computers are equipped with thermal...Ch. 9 - Prob. 9.43PCh. 9 - At the end of its manufacturing process, a silicon...Ch. 9 - Integrated circuit (IC) boards are stacked within...Ch. 9 - Prob. 9.48PCh. 9 - Prob. 9.50PCh. 9 - Prob. 9.51PCh. 9 - Prob. 9.52PCh. 9 - Prob. 9.53PCh. 9 - Prob. 9.54PCh. 9 - Prob. 9.55PCh. 9 - Prob. 9.56PCh. 9 - Prob. 9.57PCh. 9 - A horizontal tube of 12.5-mm diameter with an...Ch. 9 - Prob. 9.60PCh. 9 - Prob. 9.61PCh. 9 - Prob. 9.63PCh. 9 - Prob. 9.64PCh. 9 - Common practice in chemical processing plants is...Ch. 9 - Consider the electrical heater of Problem 7.49. If...Ch. 9 - Prob. 9.67PCh. 9 - A billet of stainless steel, AISI 316, with a...Ch. 9 - Lone stainless steel rods of 50-mm diameter are...Ch. 9 - Hot air flows from a furnace through a...Ch. 9 - A biological fluid moves at a flow rate of...Ch. 9 - A sphere of 25-mm diameter contains an embedded...Ch. 9 - Prob. 9.79PCh. 9 - A vertical array of circuit boards is immersed in...Ch. 9 - Prob. 9.81PCh. 9 - The front door of a dishwasher of width 580 mm has...Ch. 9 - A natural convection air healer consists of an...Ch. 9 - A bank of drying ovens is mounted on a rack in a...Ch. 9 - Prob. 9.85PCh. 9 - Prob. 9.86PCh. 9 - Prob. 9.87PCh. 9 - To reduce heat losses, a horizontal rectangular...Ch. 9 - Prob. 9.89PCh. 9 - Prob. 9.90PCh. 9 - Prob. 9.91PCh. 9 - Prob. 9.92PCh. 9 - A 50-mm-thick air gap separates two horizontal...Ch. 9 - Prob. 9.94PCh. 9 - A vertical, double-pane window, which is 1 m on a...Ch. 9 - The top surface (0.5m0.5m) of an oven is 60°C for...Ch. 9 - Prob. 9.97PCh. 9 - Prob. 9.98PCh. 9 - Consider the cylindrical. 0.12-m-diamter radiation...Ch. 9 - Prob. 9.100PCh. 9 - A solar collector design consists of an inner tube...Ch. 9 - Prob. 9.104PCh. 9 - Prob. 9.105PCh. 9 - Liquid nitrogen is stored in a thin-walled...Ch. 9 - Prob. 9.108PCh. 9 - Prob. 9.109PCh. 9 - Prob. 9.110PCh. 9 - Prob. 9.111PCh. 9 - Prob. 9.114PCh. 9 - Prob. 9.115PCh. 9 - Prob. 9.116PCh. 9 - Prob. 9.117PCh. 9 - A water bath is used to maintain canisters...Ch. 9 - On a very Still morning, the surface temperature...Ch. 9 - Fuel cells similar to the PEM cell of Example 1.5...
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