Convective heat loads

In Eq. (35), the subscripts s and c denote the sample and the surrounding chamber, respectively. The first term oti the right-hand side is the cooling power derived earlier (Eq. 14) the second term is the convective heat load, Pconv, given by the sample area, Ag, and the convective heat transfer coefficient, Kh, the third term is the cmiductive heat load, Pcond, given by the... 

The total heat load is introduced by each source by convection and radiation ... 

The total convective component of the heat load introduced by each source is... 

Non-condensables >70 per cent assume the heat transfer is by forced convection only. Use the correlations for forced convection to calculate the heat-transfer coefficient, but include the latent heat of condensation in the total heat load transferred. 

Changes in convective heat transfer coefficients due to autoclave position and loading scheme are difficult to model. These coefficients are more easily correlated from experimental data. This correlation can be determined from monitoring thermocouples attached to tools or by correlating air flow based on autoclave position. These coefficients are crucial for determining the rate of heat transfer from the autoclave environment into the part. Heat transfer coefficients are also a function of autoclave pressure however, the adjustment for... 

It should be noted that Lewis number, Le, is only a prediction. In reality, Le is closer to 0.9. The manner in which Equation 5.29 was derived produces an error only in the convective heat transfer coefficient. In normal cooling tower operation, convective heat transfer is generally less than 20% of the total heat load. For now, Equation 5.29 represents the centerpiece of our... 

One operating concern for a rich combustor is the occurrence of high combustor wall temperatures. In a fuel-rich combustor, air cannot be used to film-cool the walls and other techniques (e.g., fin cooling) must be employed. The temperature rise of the primary combustor coolant was measured and normalized to form a heat flux coefficient which included both convective and radiative heat loads. Figure 7 displays the dependence of this heat flux coefficient on primary combustor equivalence ratio. These data were acquired in tests in which the combustor airflow was kept constant. If convective heat transfer were the dominant mechanism a constant heat flux coefficient of approximately 25 Btu/ft -hr-deg F would be expected. The higher values of heat flux and its convex character indicate that radiative heat transfer was an important mechanism. 

One of the most effective reformer modifications is to use heat from the convection section to preheat radiant section feed. This will reduce radiant section heat load, reduce radiant section firing rate, and potentially unload other areas such as steam generation. This option has been used to increase capacity by 10 percent without increasing the arch temperature in the radiant section.86... 

D. From C we know that conductive/convective heat loss is 189 W m2, and we also know that the total heat load from net radiation is 300 W m 2. Therefore, the amount of energy that must be dissipated as latent heat through transpiration is... 

The two types of processes currently used in dry-heat sterilization include 1) dry-heat batch sterilization/ oven sterilization and 2) dry-heat tunnel sterilization. Process 1 is the type of dry heat unit widely used in the pharmaceutical industry it uses the principle of convective heat transfer to heat the load. Process 2 is only found in large-scale processes, and the main application of this process is in the sterilization and depyrogenation of glass.f ... 

The boundary condition at the inner (top) surface of the load is exposed to the radiative and convective heat q"ot such that... 

The 5°K/hr warm-up rate is equivalent to a 0.1-w refrigeration load at 15°K. During the initial (higher) heat loss period, the helium pressure in the cold-plate circuitry was atmospheric and thus representative of the rate of natural convection heat transfer from the cold plate to the external cooling stream. 

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