Boilers & heat Exchangers

CFD Analysis of Earth to Air Heat Exchanger System (ETAHE or ETAHX)




Schematic diagram of Earth to air Heat Exchanger


Computation diagram of the Earth to air Heat Exchanger

Primary Objective:
  1. To calculate the outlet temperature of the fluid and to optimize the efficiency of the ETAHE by changing the variables.
  2. Parametric study of the optimized ETAHE.
Assumptions:
  1. Air in soil is a poor conductor.
    (It reduces the efficiency of solid and liquid phases to conduct heat)
  2. Solid phase has the highest conductivity.
    (Variability of solid moisture that largely determines thermal conductivity)
  3. Variation in temperature properties are high at the surface and reduces as depth increases
  4. Thermal log
  5. Extensive field measurements conducted at various locations in U.S reveals temperature below 6feet remains constant. Ref: [Kusuda and Achenkach(1965)]
  6. According to a model developed by Bansal et al(1985), annual soil temperature in New Delhi, India at 4m depth remains relatively constant for various soil properties and various surface conditions.
    [Based on the same analysis, constant temperature at 4m depth can be 17C for wet shady surfaces to 52C for dry glazed surface under the same climate.]
  7. But in order to calculate the outlet air temperature we need to find out the Convective heat transfer coefficient. This can be done by validation of experimental data(of similar projects). Validation also helps to know the accuracy of the CFD result

Based on the above assumptions CFD simulation was carried out to optimize the efficiency of the ETAHE. The parametric study also helped in relating parameters.

Optimization of Shell and Tube heat exchanger




Optimization of shell and tube heat exchanger

Increasing the heat transfer rate of shell and tube heat exchanger by calculating velocity and temperature distribution in the system using Computational Fluid Dynamics for different geometric variation to match our customer's needs.


Optimization of boiler
  1. The objective of this project is to increase the efficiency of a fire tube boiler.
  2. CFD simulation has been done to optimize the location of the fire tubes in the boiler.