Flow balancing

The most impoi tant factor affecting product quahty is the material balance. In separating a feed stream F into distillate D and bottom B products, an overall mole-flow balance must be maintained ... 

Heat flow balance for the lower zone walls ... 

The mass flow total /j for each zone i is set up flows through the individual conductances connected with zone nj, number of conductances connected with zone i), and the requirement of mass flow balance for each zone i leads to the iterative solution for the unknown zone pressures p = (pj, pj,..., Pi)-... 

We come back to derive the process transfer functions for the blending problem.9 The total mass flow balance is... 

When performing chemical reactions it is necessary to consider conceivable deviations (e.g., upsets, abnormal situations, failures) from the normal operation of a process and equipment and their possible effects on the reaction enthalpy AHr, the gas volume M produced and the rate of gas production (dM/dt), the heat flow balance (dQR/dt) - (dQ /dt) and the maximum permissible temperature TeXo for thermal stability under the applicable process conditions. Upsets (abnormal situations, failures) can be divided into two categories, and their consequences can be assessed using the following tables3 ... 

Almost all new systems have need of adjustment of flow balances, level switch adjustment, or injection rates. A normal system start-up operation should consist of daily monitoring until the system stabilizes at a relatively constant rate. At the end... 

In mould design, flow balance avoids warpage. 

Box 1. Initial estimates of the stage temperatures are taken from linear variations between estimated overhead dewpoint and bottoms bubblepoint temperatures. Those of the vapor rates are based on the assumption of constant molal overflow with due regard to sidestreams, and those of the liquid rates are made consistent with the material flow balances. 

By looking at the molar flow balance for the jth tray in Figure 6.17 we find that... 

Steady-state isothermal heat-flow balance of a general type of reaction calorimeter... 

It is necessary to note that the matrix K does not deal with the hold-ups at all. The same rule for its construction was suggested in [8,9] on the basis of particle fractions flows balance only, without referring to Markov chains models. Here it was obtained as a particular case of the developed model, which is presented by the matrix P and allows describing also the evolution of hold-ups in general case provided the smaller matrices of P are known. 

A manifold that generates a uniform sheet must deliver a constant throughput along the die land. Performing a flow balance within the differential element, presented in Fig. 6.11,... 

Fig. 12.50 Contours of the ratio V/F0bj corresponding to some steps of the optimization procedure employed by Nobrega et al. (86,87) [Reprinted by permission from J. M. Nobrega, O. S. Cameiro, R J. Oliveira, F. T. Pinho, Flow Balancing in Extrusion Dies for Thermoplastic Profiles, Part III Experimental Extrusion, Intern. Polym. Process., 19, 225 (2004).]...

The control systems enabled in the simulation were i) the IHX flow balance controller, which acts through primary compressor speed to maintain equal flow rate on the hot and cold sides of the IHX ii) the bypass flow controller which acts through bypass valve loss coefficient to maintain a shaft speed set point. Additionally the pre-cooler and intercooler cold side flow rates are supplied as forcing functions. The flow rates were roughly matched to decay heat level. The PCU shaft set point is decreased from 60 Hz over time to have the shaft speed more or less track the decreasing reactor energy production rate. 

A flow-balancing bias canbe superimposed on direct pressure control. This control system can distribute the load between the two machines in the order of their efficiencies. 

Compute filtrate flowrate by developing solids balance and flow balance equations. First, develop the daily solids balance equation ... 

We may model complex systems by top-down or bottom-up approaches. In the top-down approach, we describe the components from the systemic behavior of the actual system. For example, from the flow balance analysis in a steady-state bacterium, we learn the input and output flows, topology of the network, and the rates of maty metabolic reactions. 

In the case of a practical heat engine an energy balance and a flow balance are made up based on knowledge of turbine blade, heat exchanger and other characteristics. An exergy account, or entropy balance, then establishes the detail of the losses or irreversibilities. No such losses occur in the equilibrium of Figure A.I. See Figure 2.2 of Barclay (1998). 

Matter (Flow) Balance, Metabolic Strategy and Estimation of Loss Processes (Exit Order) Within Autocatalytic Biochemical Cycles... 

---