Internal heat source

ISO 5657, Reaction to Fire Tests—Ignitability of Building Products Using a Radiant Heat Source, International Organization for Standardization, Geneva, Switzerland. 

Proper selection and sizing of ventilation systems require knowledge of emissions from internal contaminant and heat sources and an understanding of the mechanisms and characteristics of air and contaminant movement. 

The application of the strategies in system selection can be illustrated by using a simple example. Let us think about an industrial hail with some internal heat sources but without any remarkable internal movement that would disturb the stratification. 

Radiation from internal heat sources is not directly considered in thermal comfort calculations. 

The thermal behavior of a zone is affected by the presence of internal heat sources and by HVAC operating features, which are dealt in the next sections. 

For a person at a certain location in a room, direct radiation from internal heat sources may significantly affect the thermal comfort level. However, in the codes, room (or operative) temperatures are calculated on the basis of the room air and the wall surface temperatures only (both calculated considering the internal heat source, however). 

The thertnal model consists of two zones (Fig. 11,54). The hall is modeled w ith an air node for the occupied zone and another air node for the rest of the hall. The main heat source in the hall is the insnlatiou through the glazed roof. Additional internal hear sources are rather marginal and therefore are nor considered in the simuiation. 

Pressure relief must be adequate to prevent internal pressures from rising over 10% above the maximum allowable working pressure, except when the excess pressure is developed by external fire or other unforseen heat source. See design details in later paragraph. Papa [85] proposes an improved technique for relief sizing. Also see Figures 7-7A and 7-7B. 

Internal heat sources - lights, people, machines, etc. - sensible and latent heat... 

In addition to stable elements, radioactive elements are also produced in stars. The unstable but relatively long-lived isotopes °K, Th, and make up the internal heat source that drives volcanic activity and processes related to internal convection in the terrestrial planets. The short-lived transuranium elements such as Rn and Ra that are found on the Earth are all products of U and Th decay. 

Fig. 5.5 Experimental setup. The diode laser is frequency scanned by one waveform generator, while the other controls the modulation. The light couples from a tapered fiber into and back out of microsphere WGMs, and the throughput is detected. A polarizing beamsplitter (PBS) separates throughput of the two polarizations. A diode pumped solid state laser can be used as an external heat source for the microsphere, and the vacuum chamber allows control over the ambient pressure. Reprinted from Ref. 5 with permission. 2008 International Society for Optical Engineering...

In an ICES that serves both small and large buildings, the surplus internal heat from the large buildings can be used to provide source heat to smaller ones. An ICES in areas with moderate winter temperatures may use air as a heat source. Systems that use lakes or reservoirs rely on the natural collection of heat by these water sources throughout the year. 

The actual finite-time Rankine cycle is shown in Fig. 7.17. The cycle is an external and internal irreversible cycle that consists of two irreversible internal adiabatic processes (pump and turbine) and two irreversible external isobaric heat-transfer processes. The heat source and heat sink are... 

Fischer K., Seume J. (2006) Location and magnitude of heat sources in solid oxide fuel cells. In Proceedings of the 4th International ASME Conference on Fuel Cell Science, Engineering and Technology, FUELCELL2006, ASME, American Society of Mechanical Engineers, Paper... 

This equation simply states that the increase in internal energy of a fluid element riding with the stream is due to the heat flux, the reversible increase of internal energy per unit volume by compression, and viscous dissipation or the irreversible conversion of internal friction to heat. Should there be another type of heat source (e.g., chemical reaction), it can be added to the equation. 

The equation of thermal energy (Eq. 2.9-16) for transient conduction in solids without internal heat sources reduces to... 

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