Hubbry Logo
search
logo

Thermal hydraulics

logo
Community Hub0 Subscribers
Write something...
Be the first to start a discussion here.
Be the first to start a discussion here.
See all
Thermal hydraulics

Thermal hydraulics (also called thermohydraulics) is the study of hydraulic flow in thermal fluids. The area can be mainly divided into three parts: thermodynamics, fluid mechanics, and heat transfer, but they are often closely linked to each other. A common example is steam generation in power plants and the associated energy transfer to mechanical motion and the change of states of the water while undergoing this process. Thermal-hydraulics analysis can determine important parameters for reactor design such as plant efficiency and coolability of the system.

The common adjectives are "thermohydraulic", "thermal-hydraulics" and "thermalhydraulics".

In the thermodynamic analysis, all states defined in the system are assumed to be in thermodynamic equilibrium; each state has mechanical, thermal, and phase equilibrium, and there is no macroscopic change with respect to time. For the analysis of the system, the first law and second law of thermodynamics can be applied.

In power plant analysis, a series of states can comprise a cycle. In this case, each state represents condition at the inlet/outlet of individual component. The example of components are pumpcompressor, turbine, reactor, and heat exchanger. By considering the constitutive equation for the given type of fluid, thermodynamic state of each point can be analyzed. As a result, the thermal efficiency of the cycle can be defined.

Examples of the cycle include the Carnot cycle, Brayton cycle, and Rankine cycle. Based on the simple cycle, modified or combined cycle also exists.

Authors observed that Thermo-hydraulic Parameter (THP) is less sensitive towards the Friction Factor Improvement Factor (FFER). The deviation between the terms (fR/fS) and (fR/fS)0.33 has been found 48 % to 64 % for the range of roughness and other parameters with (Re) 2900 – 14,000, which has been used for the present study. Therefore, to evaluate in equal proportions of enhancement in heat transfer (Nu) and friction factor (f) in the thermal systems a new parameter has been proposed and introduced by present article first author, which is more realistic and it is named as Thermo-hydraulic Improvement Parameter (THIP), and it can be evaluated as the ratio of (NNIF) to (FFIF) [Sahu et al.].

Where (NNIF)=Nusselt Number Improvement Factor and (FFIF)=Friction Factor Improvement Factor

Temperature is an important quantity to know for the understanding of the system. Material properties such as density, thermal conductivity, viscosity, and specific heat depend on temperature, and very high or low temperature can bring unexpected changes in the system. In solid, the heat equation can be used to obtain the temperature distribution inside the material with given geometries.

See all
User Avatar
No comments yet.