1. THERMAL MODELING AND INSIGHTS
Workshop at PSL, May 6th-2005
RAGHUNATH GANUGAPATI(NEWT)

2. DRILL MODEL Energy During drill
Heat Pumped to keep
the borehole from closing
Adaptive 2D mesh setup
with 100*10000 steps
(Space*Time)(FD used)
Movement of boundary(ice-water interface
at each depth tracked by the Differential
Equation (Stefan Problem))
Energy During drill
Instantaneous melting (depends on nozzle design)
Slow melting (conduction through the walls of bore hole)
Energy by Hose heating (Continuous dependent on hose material)
Energy during ream

3. HOLE-21 DRILLING

4. The Actual Data From Hole21 VS Prediction

5. TEMPERATURE PROFILES

6. OPTIMAL DRILLING
The optimal solution should produce a drill speed that leads to a targeted uniform diameter for a target deployment time for a fixed power and other system constraints.
In this case, no extra heat would be applied nor any time wasted by drilling too large a hole at any depth, which should be the goal
speed
(m/hr)
Total Energy=538GJ

7. PROFILE OF OPTIMUM BOREHOLE
Target Diameter=45cm

8. PERTURBATION STUDIES

9. SMART DRILL
Often when narrower or wider regions are seen in the hole.The driller will decide to reduce the speed by certain amount ,this cannot be smooth and precisely timed and we could have OM failure because of uneven holes
In order to have a computer make decisions that drill operator would.To learn from its decisions and optimize the strategy and a fully automated system

10. References
Check