1. A shellandtube heat exchanger must be designed to heat 2.5 kg/s of water from 15 to 85C.
The heating is to be accomplished by passing hot engine oil, which is available at 160C, through
the shell side of the exchanger. The oil is known
1. Water . nters a 2-cmdiameter, and 3-m long tube whose walls are maintained at 100C.
The water enters this tube with a bulk temperature of 25C and a volume flow rate of 3 m3/h.
What is the Reynolds number and is flow fully develop
Transient Analysis with Spatial Effects
1. Consider a 10-cm diameter ceramic ball (k: 1.5 W/m-K, a: 10'6 mZ/s) that will be removed from
a furnace and is exposed to a breeze at room temperature, where the convective coefficient is
100 W/mZ-K. if one wants
Heat Transfer Modes
1. Heat is lost steadily through a 0.5cm thick 2 m x 1 m window glass whose thermal conductivity
is 0.7 W/m-C. The inner and outer surface temperatures of the glass are measured to be 12C
and 9C, respectively. What is the rate of heat
Lumped Transient Analysis
1. A 6-cmdiameter, 10~cm|ong can filled with water initially at 25C is put into a household
refrigerator at 3C? The heat transfer coefficient on the surface of the can is 14 W/mz-K.
Assuming the temperature of the water remains u
1. A 10-cm x 12cm x 14-cm rectangular prism object made of hardwood (p: 721 kg/m3, cp = 1.26
kj/kg-C) is cooled from 100C to 90C in a room at 20C in 7 minutes. What is the approximate
heat transfer coefficient during this process? *1
1. Write the simplified heat diffusion equation for a medium that can be modeled using Cartesian
coordinate with heat transfer being two dimensional, isotropic and constant thermal
conductivity, no heat generation, and transient?
1. An electrical water (k = 0.61 W/m'K) heater uses natural convection to transfer heat from a 1cm
diameter by 0.65-m long, 110 V electrical resistance heater to the water. During operation, the
surface temperature ofthis heater is 12
1. Heat is lost at a rate of 275 W per m2 area of a 15-cm-thick wall with a thermal conductivity of
1.1 W/m-K. What is the temperature drop across the wail?
2. What is the temperature drop across an interface between a 2cm x
Eng Apps Team Project
Updated 3/28 changed mass to load in graphs.
Updated 3/30 changed the range the function runs so that it would go up
to the amount needed for breaking, also added in the tolerances for
diameter and leng