The complete Question is:
Airflow through a long, 0.15-m-square air conditioning duct maintains the outer duct surface temperature at 10°C. If the horizontal duct is uninsulated and exposed to air at 35°C in the crawlspace beneath a home, what is the heat gain per unit length of the duct? Evaluate the properties of air at 300 K. For the sides of the duct, use the more accurate Churchill and Chu correlations for laminar flow on vertical plates.
What is the Rayleigh number for free convection on the outer sides of the duct?
What is the free convection heat transfer coefficient on the outer sides of the duct, in W/m2·K?
What is the Rayleigh number for free convection on the top of the duct?
What is the free convection heat transfer coefficient on the top of the duct, in W/m2·K?
What is the free convection heat transfer coefficient on the bottom of the duct, in W/m2·K?
What is the total heat gain to the duct per unit length, in W/m?
Answers:
- 7709251 or 7.709 ×10⁶
- 4.87
- 965073
- 5.931 W/m² K
- 2.868 W/m² K
- 69.498 W/m
Explanation:
Find the given attachments for complete explanation
Answer:
B. operator error or misuse
Explanation:
A product is a failure if it is not able to achieve the anticipated life cycle as expected by the organization.
In such a case, there is a withdrawal of the product from the market as a result of its ultimate failure of a product to achieve profitability.
Four common causes of product failure are poor design, poor construction, poorly communicated operating instructions, and <u>operator error or misuse</u>
They are health care professionals that focus on the safe and effective use of medications
Answer:
691K, 543K, 725K, 1473K, 240K, 373K
Explanation:
Creep deformation of any metal is the transformational tendency of a metal to distort rapidly or slowly when attacked by any form of mechanical stress. The temperature significant for a metal to deform is gotten by the division of the actual temperature of the metal by its melting point. This is termed homologous temperature which is 0.4 or higher. It is calculated by the equation:
0.4Tm
Therefore for the listed metals...
For Nickel, 0.4Tm = 0.4 ×(1455 + 273) = 691 K
For Copper, 0.4Tm = 0.4 ×(1085 + 273) = 543 K
For Iron, 0.4Tm = 0.4 ×(1538 + 273) = 725 K
For Tungsten, 0.4Tm = 0.4 ×(3410 + 273) = 1473 K
For Lead, 0.4Tm = 0.4 × (327 + 273) = 240 K
For Aluminium, 0.4Tm = 0.4 ×(660 + 273) = 373 K
