Maximum temperature rise

Maximum temperature rise of the busbars at the rated current = 85-50 = 35°C... 

Example 3-18 Maximum Temperature Rise Using Boiler Feed Water... 

Adiabatic expansion of the air in the engine causes a maximum temperature drop of the exhaust. Adiabatic compression causes a maximum temperature rise of the compressed air. These effects combine to cause the greatest work loss of any compressed-air system, when pressurized air must be cooled back to atmospheric temperature. The energy analysis parallels the one just made for the polytropic system. This shows that net areas on both PV and TS graphs measure the work lost. 

Using a hot oil system for heat transfer, the maximum temperature rise observed within the reactor at 98-99 % HBr conversion was only about 13 °C at a reactor... 

In order to calculate the operative log a-iv value a relation is required between the temperature rise in the contact area and the sliding speed. According to Carslaw and Jaeger [30] the maximum temperature rise, occurring for rubber near the end of the contact area, is given by the following relation ... 

The need to limit the maximum temperature rise has resulted in two main types of apparatus, illustrated in Fig. 20-25. The first consists of multicomponent ribbon separation units—apparatus capable of separating small quantities of mixtures which may contain few or many species. In general, such units operate with high voltages, low... 

Polymer sample temperature, measured with a thermocouple situated beneath a thin glass platform supporting the sample, depended on etch rate of the polymer the maximum temperature rise encountered in any run was 9 K, exhibited by TB after 20 min exposure to 0(3P). The... 

Test Interpretation and Continuation. Consider any temperature decreases as zero rise. If no rabbit shows an individual rise in temperature of 0.6° or more above its respective control temperature, and if the sum of the three individual maximum temperature rises does not exceed 1.4°, the product meets the requirements for the absence of pyrogens. If any rabbit shows an individual temperature rise of 0.6° or more, or if the sum of the three individual maximum temperature rises exceeds 1.4°, continue the test using five other rabbits. If not more than three of the eight rabbits show individual rises in temperature of 0.6° or more, and if the sum of the eight individual maximum temperature rises does not exceed 3.7°, the material under examination meets the requirements for the absence of pyrogens. 

Solving the energy equation provides prediction of the temperature distribution and its effect on cell performance in a PEFC. Figure 12 presents a temperature distribution in the middle of the membrane for a single-channel PEFC. The maximum temperature rise in this case is 4 °C, which will only fect cell performance slightly. However, the temperature variation depends strongly on the thermal conductivities of the GDL and flow plate as well as thermal boundary conditions. 

A T(. is the maximum temperature rise which can occur without causing ignition and, since E/R is normally quite large, very little self-heating may be needed to bring about explosion. For example, when Tg == 350 K and E = 100 kJ mol , ATc = 10.2 K. The critical reactant concentration,... 

The UL 2085 tank construction is intended to limit the heat transferred to the primary tank when the AST is exposed to a 2-h hydrocarbon pool fire of 1093°C (2000°F). The tank must be insulated to withstand the test without leakage and with an average maximum temperature rise on the primary tank not exceeding 2TC (260 F). Temperatures on the inside surface of the primary tank cannot exceed 204°C (400°F). 

The temperature rise in %-inch thick samples was also measured and calculated, although no %-inch samples were used for creep measurements. The measured maximum temperature rise was 41.5°C., and the calculated temperature rise was 41.7°C. The bulk of the study reported here is for 0.033-inch thick polystyrene samples, and for the typical conditions of this work the average temperature rise is 63.5% of the maximum temperature rise or 1.8°C. 

In a similar way, the maximum temperature rise possible in the system (the adiabatic temperature rise ATad) has a dimensionless measure 0ad given by... 

The new period-2 limit cycle is born with a CFM equal to + 1. This decreases rapidly as we reduce rN further. Eventually, the CFM approaches — 1 again a second period doubling occurs at tn = 0.137 307 1, where a period-2 with zp = 3.408 gives way to a period-4 solution with rp = 6.816. The initial splitting in the phase space trajectory again occurs in the vicinity of the maximum temperature rise and the double circuit gives way to four loops as shown in the sequence in Fig. 13.22. 

Maximum Temperature Rise Exhibited by Various Substarices Reacting with Water. W 10... 

Substance Quantities Maximum Temperature Rise Recorded, AT °F Time to Maximum Temperature, tm min Spontaneous Ignition Toxic Gas... 

COMBUSTOR INLET AIR TEMPERATURE. The effect of decreasing inlet static temperature is similar to the effect of decreasing pressure—i.e., lowered efficiency, lowered maximum temperature rise, and narrowing of the operable fuel-air range. This temperature effect is apparently due to a decreasing rate of chemical reaction with decreasing temperature and changes in evaporation rates of fuel droplets. 

Equations (19) and (20) correspond to the familiar case of uptake controlled by external heat transfer resistance derived earlier by King and Cassie [25]. Equation (20) shows that (T -T ) is the maximum temperature rise in the adsorbent for this case, and it occurs at t = 0. 

The form of equation (21) is interesting. It shows that the uptake curve for a system controlled by heat transfer within the adsorbent mass has an equivalent mathematical form to that of the isothermal uptake by the Fickian diffusion model for mass transfer [26]. The isothermal model hag mass diffusivity (D/R ) instead of thermal diffusivity (a/R ) in the exponential terms of equation (21). According to equation (21), uptake will be proportional to at the early stages of the process which is usually accepted as evidence of intraparticle diffusion [27]. This study shows that such behavior may also be caused by heat transfer resistance inside the adsorbent mass. Equation (22) shows that the surface temperature of the adsorbent particle will remain at T at all t and the maximum temperature rise of the adsorbent is T at the center of the particle at t = 0. The magnitude of T depends on (n -n ), q, c and (3, and can be very small in a differential test. 

Figure 2 shows the corresponding temperature profiles at the center and the surface of the adsorbent mass calculated by equation (8). The maximum temperature rises at the center and the surface are, respectively, only 0.64°C and 0.23°C. Figure 2 also shows that the maximum temperature rise occurs much earlier at the surface than at the center and the surface temperature quickly approaches that of the surrounding. 0... 

Figure 6 shows that the maximum temperature rise in the adsorbent is higher for larger values of r) and it occurs at smaller values of t. In real time, however, the maximum occurs at longer times for lower k for a given r) and the adsorbent cools down slower. 

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