A solar collector design consists of an inner tube enclosed concentrically in an outer tube that is transparent to solar radiation. The tubes are thin walled with inner and outer diameters of 0.08 and 0.10 m, respectively. The annular space between the tubes is completely enclosed and filled with air at atmospheric pressure. Under operating conditions for which the inner and outer tube surface temperatures are 80 and 30°C, respectively, what is the rate of convective heat loss per meter of tube length across the air space?

1. If the oxygen diffusion coefficient in tissue is assumed to be 1.1x10-5 cm2/s and fluid velocity is 1 mm/s, how large a distance between capillaries is required for convection to play an equally significant role as diffusion? Assuming an average distance between capillaries of 100 mm, does convection play a significant role? Use Peclet number to justify answers.

Using the appropriate tables, determine the change in specific entropy between the specified states, in Btu/lb · °R.

(a) water, p₁ = 10 lbf/in.², saturated vapor; p₂ = 500 lbf/in.², T₂ = 700°F.
(b) ammonia, p₁ = 140 lbf/in.², T₁ = 160°F; T₂ = -10°F, h₂ = 100 Btu/lb.
(c) air as an ideal gas, T₁ = 80°F, p₁ = 1 atm; T₂ = 340°F, p = 5 atm.
(d) oxygen as an ideal gas, T₁ = T₂ = 520°R, p₁ = 10 atm, p₂ = 9 atm.

Based on the boiling curve why is boiling to 100% quality avoided in risers?

The number of natural gas fossil fuel power plants have now exceeded coal plants. Many of the coal plants are being converted to natural gas. Explain 4 items that would change at the plant as a result of this conversion.

a. How do dislocation junctions contribute to strengthening? b. The addition of C to Fe greatly increases the room temperature strength of the alloy, but an equal amount of C added to Ag has little effect. Why?

Using psychrometric chat to answer the questions below:

15 m³/min humid air is to be cooled using an air conditioning unit. The inlet air is at 35 °C and 60% relative humidity and should be cooled to 18 °C, at which point it will be saturated.

a) Below which temperature will condensation start occurring?

b) How much water will have condensed if cooled to 18 C (mw,out)?

c) Determine the heat removal, Qout, using the first law of thermodynamics.

1a) Superheated steam is expanded isentropically from 1000 psia and a temperature of 900 F to saturated vapor. What is the change in specific enthalpy in BTU/lbm?

1b) Steam expands isentropically in a turbine from 500 psia and 1000 F to 14.7 psia. What is the difference in specific enthalpy, in BTU/lbm, between the initial and final conditions.?

Do anyone have any strategies, guides, videos, or anything relating to identifying unsteady/steady and open/closed systems in thermodynamic problems? I am struggling to identify these features when doing problems, and the text does not explicitly state a process on determining these.

An insulated cylinder is initially divided into halves by a frictionless, thermally conducting piston. On one side of the piston is 1 m³ of a gas at 300 K, 2 bar. On the other side is 1 m³ of the same gas at 300 K, 1 bar.The piston is released and equilibrium is attained, with the piston experiencing no change of state. Employing the ideal gas model for the gas, determine

(a) the final temperature, in K.

(b) the final pressure, in bar.

(c) the amount of entropy produced, in kJ/K.

Write random effects in the following systems.

1)Traffic intersection (2)Railway station (3) Inventory System

What is involute? Draw an involute with string length more than the cicumference of the corresponding circle

a copper plate .25m in diameter at 150C is to be cooled on one side, in air with ambient temprature of 25C and h=30W/m^2k, by attaching 30 copper pin fins each 0.02m diameter and 6cm long. to the surface.calculate overall heat transfer rate and overall effectiveness

Please show simple calculations:

Problem:

Computer cooling is required to remove the waste heat produced by computer components, to keep components within permissible operating temperature limits. Components that are susceptible to temporary malfunction or permanent failure if overheated include integrated circuits such as Central processing units (CPUs), chipset, graphics cards, and hard disk drives. Cooling may be designed to reduce the ambient temperature within the case of a computer, such as by exhausting hot air, or to cool a single component or small area (spot cooling). Components commonly individually cooled include the CPU, Graphics processing unit (GPU) and the northbridge. Compare different techniques used to cool desktop computers in a Caribbean environment using a thermodynamic analysis. Get basic calculations of each technique.

Please be clear in explanation!

1. Define density, mass, weight, and specific gravity. A room is 4m wide, 5m long, and 3m high. Air pressure in the room is 110 KPa absolute and the temperature is 27C. Assuming ideal gas behaviour, determine the mass, density, and specific gravity of the air using water as reference density. (The density of water is 1000kgm-3, the molar mass of air is 29g/mol, and R=8.314 J/(kg mol)).

Let the minimum fresh air requirement for the room be 9.0 Air Change Rate per hour. That is, the complete air filling the room is completely changed 9.0 times in one hour. If the ventilation requirement is met entirely by a fan calculate the volume flow rate per hour (m3/hour) required. Determine the flow capacity of the fan in m3/s. Determine the fan casing diameter if the velocity is not to exceed 6 m/s.

2

(a) Write the expression for Fick’s first law of diffusion and explain the terms in the equation in one sentence each. Illustrate and explain the concentration gradient as a function of distance in 3-4 sentences.

b) Write down the solution for Fick’s second law of diffusion. Explain all the terms in a sentence. Denote the concentration terms in the equation (C_s, C₀ and C_x) in a schematic showing a concentration gradient profile. (In other words, sketch a typical concentration profile and explain the above terms with the help the schematic) What is the primary difference between Fick’s first law and second law of diffusion?

the name of the book is the science andn engineering of materials seventh edition, and please type your answer so that i can copy it and paste it