Drip irrigation is a means of distributing the exact amount of water a plant needs by
dripping water directly onto the root zone. It can produce up to 90% more crops than
rainfed irrigation, and reduce water consumption by 70% compared to conventional
flood irrigation. In the coming years, the demand for new, low-cost, low-power drip
irrigation technology will continue to grow, particularly in developing countries. It
will enable millions of poor farmers to rise out of poverty by growing more and higher
value crops, while not contributing to overconsumption of water. The key inhibitor to
drip adoption has been the high initial investment cost. A cost and pressure analysis
revealed that a reduction in activation pressure of pressure compensating (PC) drip
emitters - which can maintain a constant flow rate under variations in pressure, to
ensure uniform water distribution on a field - can reduce the cost of off-grid drip
systems by up to 50%. These emitter have been designed and optimized empirically
in the past. In this thesis, I present a parametric model that describes the fluid
and solid mechanics that govern the behavior of a common PC emitter architecture,
which uses a flexible diaphragm to limit flow. The model was validated by testing nine
prototypes with geometric variations, all of which matched predicted performance to
within R2 = 0.85. This parametric model was then coupled with a genetic algorithm
to achieve a lower activation pressure of 0.15 bar for not only the 8.2 lph emitter, but
also the 4, 6, 7 lph emitters. These new drip emitters, with attributes that improve
performance and lower cost, are a step closer to making drip irrigation economically
accessible to all throughout the world.