It all comes down to a few things. Cost. Weight. Size.
Cost is important when you are buying 20-30 thousand, (or more) generator sets. Availability and cost of repair parts. Donald Wills Dougles, founder of Dougles aircraft Corperation once told the Sec. Defence, that he would design and produce a high performance fighter aircraft, and provide the first 1000 planes to the government free. BUT, he was to be the sole provider of spare parts. We may think that providing the gen set made someone big bucks. But the real money was in spares. And when a company designs a piece of equipment that has odd, not off the shelf parts, it drives up cost tremendously. So to keep cost down, simple and easy was the by word. The gen set housing is just that. Simple, and easy. Yes, if you have someone gin up a top for you, it will cost a lot. But when you figure 20-30, thousand ( or more) tops, you can drive down costs dramatically.
Size. The government wanted something smaller the the previous generation gen set. It needed to be able to fit in the new trailers and trucks. It needed to fit on the new generator PU and PP, (power unit and power plant) trailers. The new PP and PP trailers are much smaller the the older generation trailers. So to keep the size down, once again, simple and easy.
Weight is is the same song, different verse.
Everyone give this much thought. How could you improve this set, and still keep the Cost, Weight and size at least where it is?
I would have liked to see an aircraft style air cleaner. They used centrifugal force, to spin the incoming air, to sling out impurities. You never need another air filter to change again in your life. Down side, cost and weight. Also, you need to increase the speed of the incoming air. I am not an engineer. But maybe you could increase the incoming air speed by using a blower, and smaller intake aprature, to create a vortex in the filter housing, strong enough to clean the air. But here I go getting expensive and complicated.
