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Chapter 1: Problem 113

What is metabolism? What is the range of metabolic rate for an average man? Why are we interested in the metabolic rate of the occupants of a building when we deal with heating and air conditioning?

Short Answer

Expert verified
Short Answer: Metabolism is the chemical processes that occur within a living organism to maintain life; it helps break down food and nutrients to produce energy. The metabolic rate of an average man ranges between 1,500 to 2,500 calories per day. In terms of heating and air conditioning systems in buildings, considering the metabolic rate of occupants is crucial to properly design and operate an energy-efficient and comfortable system, as the heat generated by human bodies contributes to the overall thermal load in the space.

Step by step solution

01

Define Metabolism

Metabolism refers to the chemical processes that occur within a living organism to maintain life. These processes help to break down food and nutrients to produce energy, which is essential for various functions of the body.
02

Provide the range of metabolic rate for an average man

The metabolic rate is the number of calories a person burns at rest to carry out basic bodily functions, such as maintaining internal body temperature, cell repair, and nutrient transport. The range of metabolic rate for an average man is typically between 1,500 to 2,500 calories per day, depending on factors like age, weight, and activity level.
03

Explain the importance of considering metabolic rates for heating and air conditioning systems in buildings

When designing heating and air conditioning systems for a building, it is essential to consider the metabolic rate of occupants. This is because the heat generated by the human body can contribute to the overall thermal load in the space. Metabolic heat production affects the cooling and heating needs of the building, as well as the comfort level of the occupants. Properly accounting for the metabolic rate of occupants can help in designing and operating an energy-efficient and comfortable heating and air conditioning system for the building, ultimately reducing energy consumption and costs.

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Most popular questions from this chapter

The inner and outer glasses of a 4-ft \(\times 4\)-ft double-pane window are at \(60^{\circ} \mathrm{F}\) and \(48^{\circ} \mathrm{F}\), respectively. If the \(0.25\)-in space between the two glasses is filled with still air, determine the rate of heat transfer through the window. Answer. $131 \mathrm{Btu} / \mathrm{h}$

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Consider a sealed 20-cm-high electronic box whose base dimensions are $40 \mathrm{~cm} \times 40 \mathrm{~cm}$ placed in a vacuum chamber. The emissivity of the outer surface of the box is \(0.95\). If the electronic components in the box dissipate a total of \(100 \mathrm{~W}\) of power and the outer surface temperature of the box is not to exceed \(55^{\circ} \mathrm{C}\), determine the temperature at which the surrounding surfaces must be kept if this box is to be cooled by radiation alone. Assume the heat transfer from the bottom surface of the box to the stand to be negligible.

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