I have successfully smoked with apple wood chunks wrapped in foil in my outdoor grill. The trick is to find a setting that will maintain ~300 F using 1/2 of the burners. Then place the foil-wrapped chunks on the hot side and the meat on the cool side. The wood will begin to smoke after 10 minutes or so.
Keep checking periodically to maintain 300 F.
I do this with already cooked sous-vide pork. It may need adjustment to cook raw meat while smoking - maybe up the temp to 350 F or so.
I adapted this technique from Kenji: http://www.seriouseats.com/2016/08/food-lab-complete-guide-sous-vide-barbecue-smoked-bbq-brisket.html:
Method 2: Using Live Smoke
If you've got yourself a kettle grill or smoker, then you can enhance your sous vide brisket through a bit of honest-to-goodness smoking. I find that by letting my brisket cool a bit (or even refrigerating it for up to a week), I can place it on the cooler side of a kettle grill that I've heated to around 300°F with charcoal and wood chunks and let it smoke for a good three hours or so before it starts to dry out at all. This is ample time to develop a deep, dark crust and to get some smoky flavor in there.
Is it better to apply that smoke before or after cooking sous vide? Well, according to folks like Meathead Goldwyn, author of the eponymous book on the science of barbecue, the flavorful compounds in smoke will adhere to and penetrate raw meat much better than they will with cooked meat. This is true, but I find that the amount of smoke flavor I get out of a post–sous vide session in the smoker is plenty for my taste buds, and smoking at the end makes the process so much more efficient. I'll stick to the post–sous vide smoke.